Olav Solgaard
Director, Edward L. Ginzton Laboratory and Robert L. and Audrey S. Hancock Professor in the School of Engineering
Electrical Engineering
Bio
The Solgaard group focus on design and fabrication of nano-photonics and micro-optical systems. We combine photonic crystals, optical meta-materials, silicon photonics, and MEMS, to create efficient and reliable systems for communication, sensing, imaging, and optical manipulation.
Academic Appointments
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Professor, Electrical Engineering
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Member, Bio-X
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Affiliate, Precourt Institute for Energy
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Member, Stanford Cancer Institute
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Affiliate, Stanford Woods Institute for the Environment
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Member, Wu Tsai Neurosciences Institute
Honors & Awards
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Fellow, IEEE (2017)
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Fellow, Norwegian Academy of Technological Sciences (2010)
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Fellow, Optical Society of America (2008)
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Member, The Royal Norwegian Society of Sciences and Letters (2008)
Professional Education
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PhD, Stanford (1992)
Patents
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M.J.F. Digonnet, O. Kilic, W. Jo, O. Solgaard, B.H. Afshar. "United States Patent 10,495,508 Phase-front-modulation sensor", Leland Stanford Junior University, Dec 3, 2019
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J.R. Landry, I. Ryosuke, M.J. Mandella, O. Solgaard. "United States Patent 10,401,605 Structured illumination in inverted light sheet microscopy", Leland Stanford Junior University, Sep 3, 2019
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I. Ryosuke, O. Solgaard, S.S. Hamann. "United States Patent 10,310,246 Converter, illuminator, and light sheet fluorescence microscope", Leland Stanford Junior University, Jun 4, 2019
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S Manosalvas-Kjono, R Quan, O Solgaard, Z Su. "United States Patent 11,192,779 Method and apparatus for evaluating electrostatic or nonlinear devices n US Patent", Stanford, May 12, 0175
2024-25 Courses
- Introduction to Electromagnetics and Its Applications
EE 42, ENGR 42 (Spr) - Introduction to Micro and Nano Electromechanical Systems
ENGR 240 (Win) -
Independent Studies (16)
- Curricular Practical Training
APPPHYS 291 (Aut, Win, Spr, Sum) - Curricular Practical Training for Electrical Engineers
EE 290A (Aut, Win, Sum) - Curricular Practical Training for Electrical Engineers
EE 290B (Aut, Win, Sum) - Curricular Practical Training for Electrical Engineers
EE 290C (Aut, Win, Sum) - Curricular Practical Training for Electrical Engineers
EE 290D (Aut, Win, Sum) - Curricular Practical Training for Electrical Engineers
EE 290E (Aut, Win, Sum) - Curricular Practical Training for Electrical Engineers
EE 290F (Aut, Win, Sum) - Curricular Practical Training for Electrical Engineers
EE 290G (Aut, Win, Sum) - Curricular Practical Training for Electrical Engineers
EE 290H (Aut, Win, Spr, Sum) - Directed Studies in Applied Physics
APPPHYS 290 (Aut, Win, Spr, Sum) - Master's Thesis and Thesis Research
EE 300 (Aut, Win, Spr, Sum) - Special Studies and Reports in Electrical Engineering
EE 191 (Aut, Win, Spr, Sum) - Special Studies and Reports in Electrical Engineering
EE 391 (Aut, Win, Spr, Sum) - Special Studies and Reports in Electrical Engineering (WIM)
EE 191W (Aut, Win, Spr, Sum) - Special Studies or Projects in Electrical Engineering
EE 190 (Aut, Win, Spr, Sum) - Special Studies or Projects in Electrical Engineering
EE 390 (Aut, Win, Spr, Sum)
- Curricular Practical Training
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Prior Year Courses
2023-24 Courses
- Introduction to Electromagnetics and Its Applications
EE 42, ENGR 42 (Spr) - Introduction to Micro and Nano Electromechanical Systems
ENGR 240 (Win) - Micro and Nano Optical Device Design
EE 334 (Aut) - Optics and Electronics Seminar
APPPHYS 483 (Win, Spr) - Taking the Pulse of the Planet
GEOPHYS 115 (Win)
2022-23 Courses
- Introduction to Electromagnetics and Its Applications
EE 42, ENGR 42 (Spr) - Introduction to Micro and Nano Electromechanical Systems
ENGR 240 (Win) - Optics and Electronics Seminar
APPPHYS 483 (Win) - Photonics Laboratory
EE 234 (Spr)
2021-22 Courses
- Introduction to Electromagnetics and Its Applications
EE 42, ENGR 42 (Spr) - Introduction to Micro and Nano Electromechanical Systems
ENGR 240 (Win) - Optics and Electronics Seminar
APPPHYS 483 (Win, Spr)
- Introduction to Electromagnetics and Its Applications
Stanford Advisees
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Doctoral Dissertation Reader (AC)
Nancy Ammar, Sara Azzouz, Dominic Catanzaro, Brian Chao, Arynn Gallegos, Manu Gopakumar, Yakub Grzesik, Alex Hwang, Evan Laksono, Felix Mayor, Chance Ornelas-Skarin, Taewon Park, Anirudh Vijay -
Doctoral Dissertation Advisor (AC)
Annie Kroo, Anna Miller, Melanie Murillo, Carson Valdez, Clarisse Woodahl -
Master's Program Advisor
Steven Abrego, Zhen Sun -
Doctoral Dissertation Co-Advisor (AC)
Simon Bongarz -
Doctoral (Program)
Arynn Gallegos, Crystal Nattoo, Nelson Ooi, Ekin Gunes Ozaktas, Taewon Park, Jason Saunders, Carson Valdez, Samantha van Rijs
All Publications
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Moth-eye anti-reflection structures in silicon for Long Wave IR applications
JOURNAL OF MODERN OPTICS
2024
View details for DOI 10.1080/09500340.2024.2400197
View details for Web of Science ID 001314950600001
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Coupled Mode Design of Low-Loss Electromechanical Phase Shifters
MICRO-SWITZERLAND
2024; 4 (2): 334-347
View details for DOI 10.3390/micro4020021
View details for Web of Science ID 001317767900001
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High-efficiency vertically emitting coupler facilitated by three wave interaction gratings.
Optics letters
2024; 49 (9): 2373-2376
Abstract
We designed a grating coupler optimized for normal incidence and numerically demonstrate near-unity coupling in a standard 220-nm-thick silicon-on-insulator (SOI) technology. Our design breaks the vertical symmetry within the grating region by implementing three scattering sites per local period. This technique removes the need for bottom reflectors or additional material layers and can be realized using only two lithography masks. Using adjoint method-based optimization, we engineer the coupling spectrum of the grating, balancing the trade-off between peak efficiency and bandwidth. Using this technique, we simulate three devices with peak coupling efficiencies ranging between 93.4 (-0.3 dB) and 98.6% (-0.06 dB) with corresponding 1 dB bandwidths between 48 and 8 nm all centered around 1.55 m.
View details for DOI 10.1364/OL.517492
View details for PubMedID 38691722
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Subrelativistic Alternating Phase Focusing Dielectric Laser Accelerators.
Physical review letters
2024; 132 (8): 085001
Abstract
We demonstrate a silicon-based electron accelerator that uses laser optical near fields to both accelerate and confine electrons over extended distances. Two dielectric laser accelerator (DLA) designs were tested, each consisting of two arrays of silicon pillars pumped symmetrically by pulse front tilted laser beams, designed for average acceleration gradients 35 and 50 MeV/m, respectively. The DLAs are designed to act as alternating phase focusing (APF) lattices, where electrons, depending on the electron-laser interaction phase, will alternate between opposing longitudinal and transverse focusing and defocusing forces. By incorporating fractional period drift sections that alter the synchronous phase between ±60° off crest, electrons captured in the designed acceleration bucket experience half the peak gradient as average gradient while also experiencing strong confinement forces that enable long interaction lengths. We demonstrate APF accelerators with interaction lengths up to 708 μm and energy gains up to 23.7±1.07 keV FWHM, a 25% increase from starting energy, demonstrating the ability to achieve substantial energy gains with subrelativistic DLA.
View details for DOI 10.1103/PhysRevLett.132.085001
View details for PubMedID 38457729
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Scalable low-latency optical phase sensor array
OPTICA
2023; 10 (9): 1165-1172
View details for DOI 10.1364/OPTICA.494612
View details for Web of Science ID 001167720400001
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Experimental evaluation of digitally verifiable photonic computing for blockchain and cryptocurrency
OPTICA
2023; 10 (5): 552-560
View details for DOI 10.1364/OPTICA.476173
View details for Web of Science ID 000996342500003
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Experimentally realized in situ backpropagation for deep learning in photonic neural networks.
Science (New York, N.Y.)
2023; 380 (6643): 398-404
Abstract
Integrated photonic neural networks provide a promising platform for energy-efficient, high-throughput machine learning with extensive scientific and commercial applications. Photonic neural networks efficiently transform optically encoded inputs using Mach-Zehnder interferometer mesh networks interleaved with nonlinearities. We experimentally trained a three-layer, four-port silicon photonic neural network with programmable phase shifters and optical power monitoring to solve classification tasks using "in situ backpropagation," a photonic analog of the most popular method to train conventional neural networks. We measured backpropagated gradients for phase-shifter voltages by interfering forward- and backward-propagating light and simulated in situ backpropagation for 64-port photonic neural networks trained on MNIST image recognition given errors. All experiments performed comparably to digital simulations ([Formula: see text]94% test accuracy), and energy scaling analysis indicated a route to scalable machine learning.
View details for DOI 10.1126/science.ade8450
View details for PubMedID 37104594
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Power monitoring in a feedforward photonic network using two output detectors
NANOPHOTONICS
2023
View details for DOI 10.1515/nanoph-2022-0527
View details for Web of Science ID 000909801000001
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Integrated Amplitude and Phase Monitor for Micro-Actuators.
Micromachines
2022; 13 (8)
Abstract
Micro-actuators driven on resonance maximize reach and speed; however, due to their sensitivity to environmental factors (e.g., temperature and air pressure), the amplitude and phase response must be monitored to achieve an accurate actuator position. We introduce an MEMS (microelectromechanical system) amplitude and phase monitor (MAPM) with a signal-to-noise ratio of 51 dB and 11.0 kHz bandwidth, capable of simultaneously driving and sensing the movement of 1D and 2D electrostatically driven micro-actuators without modifying the chip or its packaging. The operational principle is to electromechanically modulate the amplitude of a high-frequency signal with the changing capacitance of the micro-actuator. MAPM operation is characterized and verified by simultaneously measuring the amplitude and phase frequency response of commercial micromirrors. We demonstrate that the MAPM circuitry is insensitive to complex relationships between capacitance and position of the MEMS actuators, and it is capable of giving real-time read-out of the micromirror motion. Our measurements also reveal and quantify observations of phase drift and crosstalk in 2D resonant operation. Measurements of phase changes over time under normal operation also verify the need for phase monitoring. The open-loop, high-sensitivity position sensor enables detailed characterization of dynamic micro-actuator behavior, leading to new insights and new types of operation, including improved control of nonlinear motion.
View details for DOI 10.3390/mi13081360
View details for PubMedID 36014282
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Immersion graded index optics: theory, design, and prototypes.
Microsystems & nanoengineering
2022; 8: 69
Abstract
Immersion optics enable creation of systems with improved optical concentration and coupling by taking advantage of the fact that the luminance of light is proportional to the square of the refractive index in a lossless optical system. Immersion graded index optical concentrators, that do not need to track the source, are described in terms of theory, simulations, and experiments. We introduce a generalized design guide equation which follows the Pareto function and can be used to create various immersion graded index optics depending on the application requirements of concentration, refractive index, height, and efficiency. We present glass and polymer fabrication techniques for creating broadband transparent graded index materials with large refractive index ranges, (refractive index ratio)2 of ~2, going many fold beyond what is seen in nature or the optics industry. The prototypes demonstrate 3x optical concentration with over 90% efficiency. We report via functional prototypes that graded-index-lens concentrators perform close to the theoretical maximum limit and we introduce simple, inexpensive, design-flexible, and scalable fabrication techniques for their implementation.
View details for DOI 10.1038/s41378-022-00377-z
View details for PubMedID 35769230
View details for PubMedCentralID PMC9234043
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Acoustic Localization With an Optical Fiber Silicon Microphone System
IEEE SENSORS JOURNAL
2022; 22 (10): 9408-9416
View details for DOI 10.1109/JSEN.2022.3164597
View details for Web of Science ID 000795148500029
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High gradient silicon carbide immersion lens ultrafast electron sources
JOURNAL OF APPLIED PHYSICS
2022; 131 (13)
View details for DOI 10.1063/5.0086321
View details for Web of Science ID 000788718800005
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Quantum Nature of Dielectric Laser Accelerators
PHYSICAL REVIEW X
2021; 11 (4)
View details for DOI 10.1103/PhysRevX.11.041042
View details for Web of Science ID 000726717900001
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Thermally-Compensated Optical Fiber Silicon Sensor Platform
IEEE SENSORS JOURNAL
2021; 21 (21): 24121-24128
View details for DOI 10.1109/JSEN.2021.3112066
View details for Web of Science ID 000712581600050
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Electron Pulse Compression with Optical Beat Note.
Physical review letters
2021; 127 (16): 164802
Abstract
Compressing electron pulses is important in many applications of electron beam systems. In this study, we propose to use optical beat notes to compress electron pulses. The beat frequency is chosen to match the initial electron pulse duration, which enables the compression of electron pulses with a wide range of durations. This functionality extends the optical control of electron beams, which is important in compact electron beam systems such as dielectric laser accelerators. We also find that the dominant frequency of the electron charge density changes continuously along its drift trajectory, which may open up new opportunities in coherent interaction between free electrons and quantum or classical systems.
View details for DOI 10.1103/PhysRevLett.127.164802
View details for PubMedID 34723609
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Electron Pulse Compression with Optical Beat Note
PHYSICAL REVIEW LETTERS
2021; 127 (16)
View details for DOI 10.1103/PhysRevLett.127.164802
View details for Web of Science ID 000707499800003
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Resonant scanning design and control for fast spatial sampling.
Scientific reports
2021; 11 (1): 20011
Abstract
Two-dimensional, resonant scanners have been utilized in a large variety of imaging modules due to their compact form, low power consumption, large angular range, and high speed. However, resonant scanners have problems with non-optimal and inflexible scanning patterns and inherent phase uncertainty, which limit practical applications. Here we propose methods for optimized design and control of the scanning trajectory of two-dimensional resonant scanners under various physical constraints, including high frame-rate and limited actuation amplitude. First, we propose an analytical design rule for uniform spatial sampling. We demonstrate theoretically and experimentally that by expanding the design space, the proposed designs outperform previous designs in terms of scanning range and fill factor. Second, we show that we can create flexible scanning patterns that allow focusing on user-defined Regions-of-Interest (RoI) by modulation of the scanning parameters. The scanning parameters are found by an optimization algorithm. In simulations, we demonstrate the benefits of these designs with standard metrics and higher-level computer vision tasks (LiDAR odometry and 3D object detection). Finally, we experimentally implement and verify both unmodulated and modulated scanning modes using a two-dimensional, resonant MEMS scanner. Central to the implementations is high bandwidth monitoring of the phase of the angular scans in both dimensions. This task is carried out with a position-sensitive photodetector combined with high-bandwidth electronics, enabling fast spatial sampling at [Formula: see text] Hz frame-rate.
View details for DOI 10.1038/s41598-021-99373-y
View details for PubMedID 34625586
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Low-Energy-Spread Attosecond Bunching and Coherent Electron Acceleration in Dielectric Nanostructures
PHYSICAL REVIEW APPLIED
2021; 15 (2)
View details for DOI 10.1103/PhysRevApplied.15.L021002
View details for Web of Science ID 000628654500001
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Optical Fiber Photonic Crystal Hydrophone for Cellular Acoustic Sensing
IEEE ACCESS
2021; 9: 42305–13
View details for DOI 10.1109/ACCESS.2021.3066150
View details for Web of Science ID 000633619500001
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Optical Fiber Photonic Crystal Hydrophone for Acoustic Bio-Sensing
IEEE. 2021
View details for Web of Science ID 000831479803239
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MEMS Photonic Networks For Parallelized Matrix Multiplication Using Wavelength-Division Multiplexing
IEEE. 2021
View details for Web of Science ID 000831479800025
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Wavelength-Division Multiplexed Optical Cryptocurrency
IEEE. 2021
View details for Web of Science ID 000831479800115
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Novel Materials-based Laser Acceleration
IEEE. 2021
View details for Web of Science ID 000831479803055
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Fast Spatial Sampling with Phase Controlled Resonant Scanner
IEEE. 2021
View details for Web of Science ID 000831479801194
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Operating modes of dual-grating dielectric laser accelerators
PHYSICAL REVIEW ACCELERATORS AND BEAMS
2020; 23 (11)
View details for DOI 10.1103/PhysRevAccelBeams.23.114001
View details for Web of Science ID 000598051300001
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Conjugated MEMS Phased Arrays for Large Field of View Random Access Scanning
IEEE PHOTONICS TECHNOLOGY LETTERS
2020; 32 (20): 1291–94
View details for DOI 10.1109/LPT.2020.3021910
View details for Web of Science ID 000571742200002
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Design of a multichannel photonic crystal dielectric laser accelerator
PHOTONICS RESEARCH
2020; 8 (10): 1586–98
View details for DOI 10.1364/PRJ.394127
View details for Web of Science ID 000577372300009
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Optical Fiber-Facet Multiplexed Monolithic Silicon Pressure Sensors
IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC. 2020: 10598–606
View details for DOI 10.1109/JSEN.2020.2993770
View details for Web of Science ID 000575389000030
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Parallel Programming of an Arbitrary Feedforward Photonic Network
IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS
2020; 26 (5)
View details for DOI 10.1109/JSTQE.2020.2997849
View details for Web of Science ID 000557444000001
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Self-aligned concentrating immersion-lens arrays for patterning and efficiency recovery in scaffold-reinforced perovskite solar cells
APPLIED MATERIALS TODAY
2020; 20
View details for DOI 10.1016/j.apmt.2020.100704
View details for Web of Science ID 000598351900009
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Random Access Cylindrical Lensing and Beam Steering Using a High-Speed Linear Phased Array
IEEE PHOTONICS TECHNOLOGY LETTERS
2020; 32 (14): 859–62
View details for DOI 10.1109/LPT.2020.3000614
View details for Web of Science ID 000544101700004
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SPADnet: deep RGB-SPAD sensor fusion assisted by monocular depth estimation
OPTICS EXPRESS
2020; 28 (10): 14948–62
Abstract
Single-photon light detection and ranging (LiDAR) techniques use emerging single-photon detectors (SPADs) to push 3D imaging capabilities to unprecedented ranges. However, it remains challenging to robustly estimate scene depth from the noisy and otherwise corrupted measurements recorded by a SPAD. Here, we propose a deep sensor fusion strategy that combines corrupted SPAD data and a conventional 2D image to estimate the depth of a scene. Our primary contribution is a neural network architecture-SPADnet-that uses a monocular depth estimation algorithm together with a SPAD denoising and sensor fusion strategy. This architecture, together with several techniques in network training, achieves state-of-the-art results for RGB-SPAD fusion with simulated and captured data. Moreover, SPADnet is more computationally efficient than previous RGB-SPAD fusion networks.
View details for DOI 10.1364/OE.392386
View details for Web of Science ID 000538870000067
View details for PubMedID 32403527
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Software-Based Phase Control, Video-Rate Imaging, and Real-Time Mosaicing With a Lissajous-Scanned Confocal Microscope
IEEE TRANSACTIONS ON MEDICAL IMAGING
2020; 39 (4): 1127–37
Abstract
We present software-based methods for automatic phase control and for mosaicing high-speed, Lissajous-scanned images. To achieve imaging speeds fast enough for mosaicing, we first increase the image update rate tenfold from 3 to 30 Hz, then vertically interpolate each sparse image in real-time to eliminate fixed pattern noise. We validate our methods by imaging fluorescent beads and automatically maintaining phase control over the course of one hour. We then image fixed mouse brain tissues at varying update rates and compare the resulting mosaics. Using reconstructed image data as feedback for phase control eliminates the need for phase sensors and feedback controllers, enabling long-term imaging experiments without additional hardware. Mosaicing subsampled images results in video-rate imaging speeds, nearly fully recovered spatial resolution, and millimeter-scale fields of view.
View details for DOI 10.1109/TMI.2019.2942552
View details for Web of Science ID 000525265800029
View details for PubMedID 31567074
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Optical Fiber-Tip Monolithic Silicon Pressure Sensors
IEEE SENSORS JOURNAL
2020; 20 (5): 2476–84
View details for DOI 10.1109/JSEN.2019.2952546
View details for Web of Science ID 000522451400027
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Gallium Oxide for High-Power Optical Applications
ADVANCED OPTICAL MATERIALS
2020
View details for DOI 10.1002/adom.201901522
View details for Web of Science ID 000507932100001
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Surface treatments of dielectric laser accelerators for increased laser-induced damage threshold
OPTICS LETTERS
2020; 45 (2): 391–94
View details for DOI 10.1364/OL.379628
View details for Web of Science ID 000510865100034
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On-chip integrated laser-driven particle accelerator.
Science (New York, N.Y.)
2020; 367 (6473): 79–83
Abstract
Particle accelerators represent an indispensable tool in science and industry. However, the size and cost of conventional radio-frequency accelerators limit the utility and reach of this technology. Dielectric laser accelerators (DLAs) provide a compact and cost-effective solution to this problem by driving accelerator nanostructures with visible or near-infrared pulsed lasers, resulting in a 104 reduction of scale. Current implementations of DLAs rely on free-space lasers directly incident on the accelerating structures, limiting the scalability and integrability of this technology. We present an experimental demonstration of a waveguide-integrated DLA that was designed using a photonic inverse-design approach. By comparing the measured electron energy spectra with particle-tracking simulations, we infer a maximum energy gain of 0.915 kilo-electron volts over 30 micrometers, corresponding to an acceleration gradient of 30.5 mega-electron volts per meter. On-chip acceleration provides the possibility for a completely integrated mega-electron volt-scale DLA.
View details for DOI 10.1126/science.aay5734
View details for PubMedID 31896715
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High-speed axially swept light sheet microscopy using a linear MEMS phased array for isotropic resolution.
Journal of biomedical optics
2020; 25 (10)
Abstract
Axially swept light sheet microscopy is used for deconvolution-free, high-resolution 3D imaging, but usually the axial scan mechanism reduces the top imaging speed. Phased arrays (PAs) for axial scanning enable both high resolution and high speed.A high-speed PA with an update rate faster than the camera row read time is used to track the rolling shutter at camera-limited rates.The point spread function is evaluated to ensure sub-micron isotropic resolution, and the technique is demonstrated on a live Drosophila embryo.Isotropic resolution is shown down to 720 ± 55 nm in all three spatial dimensions. With an update rate of 2.85 μs, the PA tracks the camera sensor rolling shutter at camera-limited rates. Features in the Drosophila embryo are resolved clearly compared with the equivalent static light sheet case. The random-access nature of the PA enables a camera sensor readout in the same direction for each frame to maintain even temporal sampling in image sequences with no speed loss.Use of PAs is compatible with axially swept light sheet microscopy and offers significant improvements in speed.
View details for DOI 10.1117/1.JBO.25.10.106504
View details for PubMedID 33098281
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Observation of the Quantum Nature of Laser-Driven Particle Acceleration
IEEE. 2020
View details for Web of Science ID 000612090002104
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Parallel Fault-Tolerant Programming and Optimization of Photonic Neural Networks
IEEE. 2020
View details for Web of Science ID 000612090001197
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Broadband Optical Fiber-Facet Silicon Pressure Sensor
IEEE. 2020
View details for Web of Science ID 000612090000157
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Design of a multi-channel photonic crystal dielectric laser accelerator
IEEE. 2020
View details for Web of Science ID 000612090003182
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Net Acceleration and Direct Measurement of Attosecond Electron Pulses in a Silicon Dielectric Laser Accelerator.
Physical review letters
2019; 123 (26): 264802
Abstract
Net acceleration of attosecond-scale electron pulses is critical to the development of on-chip accelerators. We demonstrate a silicon-based laser-driven two-stage accelerator as an injector stage prototype for a Dielectric Laser Accelerator (DLA). The first stage converts a 57-keV (500±100)-fs (FWHM) electron pulse into a pulse train of 700±200 as (FWHM) microbunches. The second stage harnesses the tunability of dual-drive DLA to perform both a net acceleration and a streaking measurement. In the acceleration mode, the second stage increases the net energy of the electron pulse by 200 eV over 12.25 μm. In the deflection mode, the microbunch temporal profile is analyzed by a direct streaking measurement with 200 as resolution. This work provides a demonstration of a novel, on-chip method to access the attosecond regime, opening new paths towards attosecond science using DLA.
View details for DOI 10.1103/PhysRevLett.123.264802
View details for PubMedID 31951436
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Net Acceleration and Direct Measurement of Attosecond Electron Pulses in a Silicon Dielectric Laser Accelerator
PHYSICAL REVIEW LETTERS
2019; 123 (26)
View details for DOI 10.1103/PhysRevLett.123.264802
View details for Web of Science ID 000504647800005
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Extended Design Space of Silicon-on-Nothing MEMS
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2019; 28 (5): 850–58
View details for DOI 10.1109/JMEMS.2019.2927466
View details for Web of Science ID 000489837100014
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Matrix Optimization on Universal Unitary Photonic Devices
PHYSICAL REVIEW APPLIED
2019; 11 (6)
View details for DOI 10.1103/PhysRevApplied.11.064044
View details for Web of Science ID 000473041300001
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Tunable structured illumination light sheet microscopy for background rejection and imaging depth in minimally processed tissues.
Journal of biomedical optics
2019; 24 (4): 1–6
Abstract
We demonstrate improved optical sectioning in light sheet fluorescence microscopy using tunable structured illumination (SI) frequencies to optimize image quality in scattering specimens. The SI patterns are generated coherently using a one-dimensional spatial light modulator for maximum pattern contrast, and the pattern spatial frequency is adjustable up to half the incoherent cutoff frequency of our detection objective. At this frequency, we demonstrate background reductions of 2 orders of magnitude.
View details for PubMedID 30968649
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Tunable structured illumination light sheet microscopy for background rejection and imaging depth in minimally processed tissues
JOURNAL OF BIOMEDICAL OPTICS
2019; 24 (4)
View details for DOI 10.1117/1.JBO.24.4.046501
View details for Web of Science ID 000481879600009
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Laser-Driven Electron Lensing in Silicon Microstructures.
Physical review letters
2019; 122 (10): 104801
Abstract
We demonstrate a laser-driven, tunable electron lens fabricated in monolithic silicon. The lens consists of an array of silicon pillars pumped symmetrically by two 300 fs, 1.95 μm wavelength, nJ-class laser pulses from an optical parametric amplifier. The optical near field of the pillar structure focuses electrons in the plane perpendicular to the pillar axes. With 100±10 MV/m incident laser fields, the lens focal length is measured to be 50±4 μm, which corresponds to an equivalent quadrupole focusing gradient B^{'} of 1.4±0.1 MT/m. By varying the incident laser field strength, the lens can be tuned from a 21±2 μm focal length (B^{'}>3.3 MT/m) to focal lengths on the centimeter scale.
View details for DOI 10.1103/PhysRevLett.122.104801
View details for PubMedID 30932681
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Laser-Driven Electron Lensing in Silicon Microstructures
PHYSICAL REVIEW LETTERS
2019; 122 (10)
View details for DOI 10.1103/PhysRevLett.122.104801
View details for Web of Science ID 000461069000004
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MONOLITHIC SILICON-ON-NOTHING FIBER-BASED PRESSURE SENSORS
IEEE. 2019: 1893–96
View details for Web of Science ID 000539487000479
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Linear Micromechanical Phased Arrays
IEEE. 2019: 174–75
View details for Web of Science ID 000522410000075
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High-speed random access optical scanning using a linear MEMS phased array
OPTICS LETTERS
2018; 43 (21): 5455–58
Abstract
We demonstrate a high-speed linear microelectromechanical systems (MEMS) phase modulator capable of random access scanning at 350 kHz, so that any state can be accessed in 2.9 μs from any other state. 670 scan lines with a .87 deg field of view (FOV) are demonstrated in a Fourier regime, with a projected far-field response of 660 lines with an 18 deg FOV after magnification.
View details for DOI 10.1364/OL.43.005455
View details for Web of Science ID 000448939000072
View details for PubMedID 30383030
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Design and Fabrication of Monolithic Photonic Crystal Fiber Acoustic Sensor
IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC. 2018: 7826–32
View details for DOI 10.1109/JSEN.2018.2846788
View details for Web of Science ID 000444832100010
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Design and Fabrication of Monolithic Photonic Crystal Fiber Acoustic Sensor.
IEEE sensors journal
2018; 18 (19): 7826-7832
Abstract
Single-crystal silicon is an excellent optical and mechanical material, but its properties are compromised by the incorporation of other materials required for functionality or structural support. Here we describe a monolithic silicon acoustic sensor based on a sensing diaphragm with an integrated Photonic Crystal (PC) mirror. Diaphragm deflection is measured in a Fabry-Perot resonator formed between the PC mirror and a gold coated single-mode fiber. The sensors are fabricated on standard silicon wafers by standard CMOS processing technologies, yielding monolithic, low-stress sensing diaphragms. The packaged sensor exhibits a minimum detectable pressure of 10 μ Pa / Hz in the 8 kHz to 17 kHz frequency range.
View details for DOI 10.1109/JSEN.2018.2846788
View details for PubMedID 30923467
View details for PubMedCentralID PMC6433403
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3D printed optics with nanometer scale surface roughness
MICROSYSTEMS & NANOENGINEERING
2018; 4
View details for DOI 10.1038/s41378-018-0015-4
View details for Web of Science ID 000438771600002
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3D printed optics with nanometer scale surface roughness.
Microsystems & nanoengineering
2018; 4: 18
Abstract
Complex optical devices including aspherical focusing mirrors, solar concentrator arrays, and immersion lenses were 3D printed using commercial technology and experimentally demonstrated by evaluating surface roughness and shape. The as-printed surfaces had surface roughness on the order of tens of microns. To improve this unacceptable surface quality for creating optics, a polymer smoothing technique was developed. Atomic force microscopy and optical profilometry showed that the smoothing technique reduced the surface roughness to a few nanometers, consistent with the requirements of high-quality optics, while tests of optical functionality demonstrated that the overall shapes were maintained so that near theoretically predicted operation was achieved. The optical surface smoothing technique is a promising approach towards using 3D printing as a flexible tool for prototyping and fabrication of miniaturized high-quality optics.
View details for DOI 10.1038/s41378-018-0015-4
View details for PubMedID 31057906
View details for PubMedCentralID PMC6220180
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Elements of a dielectric laser accelerator
OPTICA
2018; 5 (6): 687–90
View details for DOI 10.1364/OPTICA.5.000687
View details for Web of Science ID 000435967000004
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Large negative and positive optical Goos-Hanchen shift in photonic crystals
OPTICS LETTERS
2018; 43 (12): 2803–6
Abstract
Low-loss photonic crystal (PC) mirrors exhibit positive and negative Goos-Hänchen shift (GHS) due to the strong angular and wavelength dependencies of their reflected phase. This Letter demonstrates the existence of large positive and negative GHS in PC mirrors through theoretical, numerical, and experimental approaches. A simple algebraic relation shows that positive effective thickness yields positive (negative) GHS for resonances that blue (red) shift with angle, while the opposite is true for interfaces with negative effective thickness. Spatiotemporal coupled-mode theory demonstrates the above relation for simple systems with one or two resonance modes, and it also shows the existence of both positive and negative GHS. These effects are numerically and experimentally verified in complex PCs with several resonance modes.
View details for DOI 10.1364/OL.43.002803
View details for Web of Science ID 000435386600020
View details for PubMedID 29905693
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On-Chip Laser-Power Delivery System for Dielectric Laser Accelerators
PHYSICAL REVIEW APPLIED
2018; 9 (5)
View details for DOI 10.1103/PhysRevApplied.9.054017
View details for Web of Science ID 000433002200001
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Phase-dependent laser acceleration of electrons with symmetrically driven silicon dual pillar gratings
OPTICS LETTERS
2018; 43 (9): 2181–84
Abstract
We present the demonstration of phase-dependent laser acceleration and deflection of electrons using a symmetrically driven silicon dual pillar grating structure. We show that exciting an evanescent inverse Smith-Purcell mode on each side of a dual pillar grating can produce hyperbolic cosine acceleration and hyperbolic sine deflection modes, depending on the relative excitation phase of each side. Our devices accelerate sub-relativistic 99.0 keV kinetic energy electrons by 3.0 keV over a 15 μm distance with accelerating gradients of 200 MeV/m with 40 nJ, 300 fs, 1940 nm pulses from an optical parametric amplifier. These results represent a significant step towards making practical dielectric laser accelerators for ultrafast, medical, and high-energy applications.
View details for DOI 10.1364/OL.43.002181
View details for Web of Science ID 000431179400061
View details for PubMedID 29714784
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Automated Cell Segmentation for Quantitative Phase Microscopy
IEEE TRANSACTIONS ON MEDICAL IMAGING
2018; 37 (4): 929–40
Abstract
Automated cell segmentation and tracking is essential for dynamic studies of cellular morphology, movement, and interactions as well as other cellular behaviors. However, accurate, automated, and easy-to-use cell segmentation remains a challenge, especially in cases of high cell densities, where discrete boundaries are not easily discernable. Here, we present a fully automated segmentation algorithm that iteratively segments cells based on the observed distribution of optical cell volumes measured by quantitative phase microscopy. By fitting these distributions to known probability density functions, we are able to converge on volumetric thresholds that enable valid segmentation cuts. Since each threshold is determined from the observed data itself, virtually no input is needed from the user. We demonstrate the effectiveness of this approach over time using six cell types that display a range of morphologies, and evaluate these cultures over a range of confluencies. Facile dynamic measures of cell mobility and function revealed unique cellular behaviors that relate to tissue origins, state of differentiation, and real-time signaling. These will improve our understanding of multicellular communication and organization.
View details for DOI 10.1109/TMI.2017.2775604
View details for Web of Science ID 000428886700010
View details for PubMedID 29610072
View details for PubMedCentralID PMC5907807
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Time-multiplexed light field synthesis via factored Wigner distribution function
OPTICS LETTERS
2018; 43 (3): 599–602
Abstract
An optimization algorithm for preparing display-ready holographic elements (hogels) to synthesize a light field is outlined, and proof of concept is experimentally demonstrated. This method allows for higher-rank factorization, which can be used for time-multiplexing multiple frames for improved image quality, using phase-only and fully complex modulation with a single spatial light modulator.
View details for DOI 10.1364/OL.43.000599
View details for Web of Science ID 000423776600064
View details for PubMedID 29400850
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Variable Focusing and Steering Using High Speed MEMS Phased Array
IEEE. 2018: 232–33
View details for Web of Science ID 000454732000114
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Optophysiology of cardiomyocytes: characterizing cellular motion with quantitative phase imaging.
Biomedical optics express
2017; 8 (10): 4652–62
Abstract
Quantitative phase imaging enables precise characterization of cellular shape and motion. Variation of cell volume in populations of cardiomyocytes can help distinguish their types, while changes in optical thickness during beating cycle identify contraction and relaxation periods and elucidate cell dynamics. Parameters such as characteristic cycle shape, beating frequency, duration and regularity can be used to classify stem-cell derived cardiomyocytes according to their health and, potentially, cell type. Unlike classical patch-clamp based electrophysiological characterization of cardiomyocytes, this interferometric approach enables rapid and non-destructive analysis of large populations of cells, with longitudinal follow-up, and applications to tissue regeneration, personalized medicine, and drug testing.
View details for PubMedID 29082092
View details for PubMedCentralID PMC5654807
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Monolithic Photonic Crystal Fiber Acoustic Sensor
IEEE. 2017: 1113–15
View details for Web of Science ID 000427677500375
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MONOLITHIC SILICON-ON-NOTHING PHOTONIC CRYSTAL PRESSURE SENSOR
IEEE. 2017: 1963–66
View details for Web of Science ID 000426701400482
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Characterizing Cardiomyocytes Motion with Quantitative Phase Imaging
IEEE. 2017
View details for Web of Science ID 000427296200175
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Light sheet fluorescence microscopy using high-speed structured and pivoting illumination
OPTICS LETTERS
2016; 41 (21): 5015-5018
Abstract
We show that light sheet fluorescence microscopy with structured and pivoting illumination enables fast image acquisition and improved image quality. A one-dimensional spatial light phase modulator is used to control the illumination profile at high speed. To demonstrate the features of the system, we image fluorescent beads and biological samples, successfully obtaining optically sectioned images with higher contrast using structured illumination and with reduced shadowing effects using pivoting illumination.
View details for DOI 10.1364/OL.41.005015
View details for Web of Science ID 000386925800042
View details for PubMedID 27805674
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Haltere-Like Optoelectromechanical Gyroscope
IEEE SENSORS JOURNAL
2016; 16 (11): 4274-4280
View details for DOI 10.1109/JSEN.2016.2539687
View details for Web of Science ID 000375563700036
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Design and fabrication of silicon-tessellated structures for monocentric imagers.
Microsystems & nanoengineering
2016; 2: 16019
Abstract
Compared with conventional planar optical image sensors, a curved focal plane array can simplify the lens design and improve the field of view. In this paper, we introduce the design and implementation of a segmented, hemispherical, CMOS-compatible silicon image plane for a 10-mm diameter spherical monocentric lens. To conform to the hemispherical focal plane of the lens, we use flexible gores that consist of arrays of spring-connected silicon hexagons. Mechanical functionality is demonstrated by assembling the 20-μm-thick silicon gores into a hemispherical test fixture. We have also fabricated and tested a photodiode array on a silicon-on-insulator substrate for use with the curved imager. Optical testing shows that the fabricated photodiodes achieve good performance; the hemispherical imager enables a compact 160 ° field of view camera with >80% fill factor using a single spherical lens.
View details for DOI 10.1038/micronano.2016.19
View details for PubMedID 31057822
View details for PubMedCentralID PMC6444745
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Fast Stiffness Mapping of Cells Using High-Bandwidth Atomic Force Microscopy.
ACS nano
2016; 10 (1): 257-264
Abstract
The cytoskeleton controls cellular morphology and mediates the mechanical interactions between a cell and its environment. Atomic force microscopy (AFM) has the unique capability to map cytoskeletal mechanics and structures with nanometer resolution. However, whole-cell cytomechanical imaging with conventional AFM techniques is limited by low imaging speed. Here, we present fast nanomechanical mapping of cells using high-bandwidth AFM (HB-AFM), where >10(6) nanoindentation measurements were acquired in ∼10 min-a task that would take weeks to finish using conventional AFM. High-bandwidth measurements enabled capture of the entire tip-sample interaction for each tap on cells, engendering a new measurement ("force phase") that exceeds the contrast of conventional tapping mode and enabling spectral visualization of >10 harmonics. The abundance of measurements allowed discovery of subtle cytomechanical features, including the stiffness of fibers of the cellular spectrin network in situ. This approach bridges HB-AFM and high-harmonic imaging and opens future opportunities for measuring the dynamic mechanical properties of living cells.
View details for DOI 10.1021/acsnano.5b03959
View details for PubMedID 26554581
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Photonic-Crystal-Based Fiber Hydrophone With Sub-100 mu Pa/root Hz Pressure Resolution
IEEE PHOTONICS TECHNOLOGY LETTERS
2016; 28 (2): 123-126
View details for DOI 10.1109/LPT.2015.2487498
View details for Web of Science ID 000366966900004
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Metal-insulator-metal waveguides for particle trapping and separation
LAB ON A CHIP
2016; 16 (12): 2302-2308
Abstract
Optical particle trapping and separation are essential techniques in the fields of biology and chemistry. In many applications, it is important to identify passive separation techniques that only rely on intrinsic forces in a system with a fixed device geometry. We present a dual-waveguide sorter that utilizes the loss of metal-insulator-metal (MIM) waveguides for completely passive particle trapping and separation and is created using a unique angle sidewall deposition process. Our experiments show that an inner Au-Si3N4-Au waveguide is able to trap particles within the propagation distance of its dominant modes and release the particles into an outer Au-H2O-Au waveguide. The outer waveguide then propels the particles and separates them by size. The separation results are accurately modeled by a first-principles, analytical model.
View details for DOI 10.1039/c6lc00366d
View details for Web of Science ID 000378944800016
View details for PubMedID 27216706
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Dynamic and social behaviors of human pluripotent stem cells
SCIENTIFIC REPORTS
2015; 5
Abstract
Human pluripotent stem cells (hPSCs) can self-renew or differentiate to diverse cell types, thus providing a platform for basic and clinical applications. However, pluripotent stem cell populations are heterogeneous and functional properties at the single cell level are poorly documented leading to inefficiencies in differentiation and concerns regarding reproducibility and safety. Here, we use non-invasive time-lapse imaging to continuously examine hPSC maintenance and differentiation and to predict cell viability and fate. We document dynamic behaviors and social interactions that prospectively distinguish hPSC survival, self-renewal, and differentiation. Results highlight the molecular role of E-cadherin not only for cell-cell contact but also for clonal propagation of hPSCs. Results indicate that use of continuous time-lapse imaging can distinguish cellular heterogeneity with respect to pluripotency as well as a subset of karyotypic abnormalities whose dynamic properties were monitored.
View details for DOI 10.1038/srep14209
View details for Web of Science ID 000361369100001
View details for PubMedID 26381699
View details for PubMedCentralID PMC4585647
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Dielectric laser acceleration of sub-100 keV electrons with silicon dual-pillar grating structures
OPTICS LETTERS
2015; 40 (18): 4344-4347
Abstract
We present the demonstration of high-gradient laser acceleration and deflection of electrons with silicon dual-pillar grating structures using both evanescent inverse Smith-Purcell modes and coupled modes. Our devices accelerate subrelativistic 86.5 and 96.3 keV electrons by 2.05 keV over 5.6 μm distance for accelerating gradients of 370 MeV/m with a 3 nJ mode-locked Ti:sapphire laser. We also show that dual pillars can produce uniform accelerating gradients with a coupled-mode field profile. These results represent a significant step toward making practical dielectric laser accelerators for ultrafast, medical, and high-energy applications.
View details for DOI 10.1364/OL.40.004344
View details for Web of Science ID 000361556700040
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Single-Crystal Silicon Photonic-Crystal Fiber-Tip Pressure Sensors
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2015; 24 (4): 968-975
View details for DOI 10.1109/JMEMS.2014.2360859
View details for Web of Science ID 000358952600024
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Optical separation of heterogeneous size distributions of microparticles on silicon nitride strip waveguides
OPTICS EXPRESS
2015; 23 (7): 8855-8866
Abstract
We demonstrate two complementary optical separation techniques of dielectric particles on the surface of silicon nitride waveguides. Glass particles ranging from 2 μm to 10 μm in diameter are separated at guided powers below 40 mW. The effects of optical, viscous, and frictional forces on the particles are modeled and experimentally shown to enable separation. Particle interactions are investigated and shown to decrease measured particle velocity without interfering with the overall particle separation distribution. The demonstrated separation techniques have the potential to be integrated with microfluidic structures for cell sorting.
View details for DOI 10.1364/OE.23.008855
View details for Web of Science ID 000352290000088
View details for PubMedID 25968723
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Dynamic and social behaviors of human pluripotent stem cells.
Scientific reports
2015; 5: 14209-?
Abstract
Human pluripotent stem cells (hPSCs) can self-renew or differentiate to diverse cell types, thus providing a platform for basic and clinical applications. However, pluripotent stem cell populations are heterogeneous and functional properties at the single cell level are poorly documented leading to inefficiencies in differentiation and concerns regarding reproducibility and safety. Here, we use non-invasive time-lapse imaging to continuously examine hPSC maintenance and differentiation and to predict cell viability and fate. We document dynamic behaviors and social interactions that prospectively distinguish hPSC survival, self-renewal, and differentiation. Results highlight the molecular role of E-cadherin not only for cell-cell contact but also for clonal propagation of hPSCs. Results indicate that use of continuous time-lapse imaging can distinguish cellular heterogeneity with respect to pluripotency as well as a subset of karyotypic abnormalities whose dynamic properties were monitored.
View details for DOI 10.1038/srep14209
View details for PubMedID 26381699
View details for PubMedCentralID PMC4585647
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Design of resonant mirrors with negative group delay
OPTICS EXPRESS
2014; 22 (23): 29213-29222
View details for DOI 10.1364/OE.22.029213
View details for Web of Science ID 000345268500141
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Optical MEMS: From Micromirrors to Complex Systems
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2014; 23 (3): 517-538
View details for DOI 10.1109/JMEMS.2014.2319266
View details for Web of Science ID 000337128200007
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Silicon buried gratings for dielectric laser electron accelerators
APPLIED PHYSICS LETTERS
2014; 104 (18)
View details for DOI 10.1063/1.4875957
View details for Web of Science ID 000336249600079
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Digital quadrature amplitude modulation with optimized non-rectangular constellations for 100 Gb/s transmission by a directly-modulated laser
OPTICS EXPRESS
2014; 22 (9): 10844-10857
Abstract
We study the performance of novel quadrature amplitude modulation (QAM) constellations for 100 Gb/s transmission by a directly-modulated laser. Due to the strong nonlinearity of a directly-modulated laser, rectangular constellations suffer a large penalty from their regular spacing between symbols. We present a method for synthesizing irregular constellations which position symbols more efficiently. We will demonstrate the improved performance of these novel constellations over the conventional rectangular constellation as well as the superior performance achievable with digital QAM compared to optimally bit-loaded discrete-multitone modulation.
View details for DOI 10.1364/OE.22.010844
View details for Web of Science ID 000335905300112
View details for PubMedID 24921784
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Double-Layer Silicon Photonic Crystal Fiber-Tip Temperature Sensors
IEEE PHOTONICS TECHNOLOGY LETTERS
2014; 26 (9): 900-903
View details for DOI 10.1109/LPT.2014.2309345
View details for Web of Science ID 000335819300003
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Monolithic silicon waveguides in bulk silicon wafers
Conference on Next-Generation Optical Networks for Data Centers and Short-Reach Links
SPIE-INT SOC OPTICAL ENGINEERING. 2014
View details for DOI 10.1117/12.2044159
View details for Web of Science ID 000338072100010
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Detection of single nano-defects in photonic crystals between crossed polarizers
OPTICS EXPRESS
2013; 21 (25): 31375-31389
Abstract
We investigate, by simulations and experiments, the light scattering of small particles trapped in photonic crystal membranes supporting guided resonance modes. Our results show that, due to amplified Rayleigh small particle scattering, such membranes can be utilized to make a sensor that can detect single nano-particles. We have designed a biomolecule sensor that uses cross-polarized excitation and detection for increased sensitivity. Estimated using Rayleigh scattering theory and simulation results, the current fabricated sensor has a detection limit of 26 nm, corresponding to the size of a single virus. The sensor can potentially be made both cheap and compact, to facilitate use at point-of-care.
View details for DOI 10.1364/OE.21.031375
View details for Web of Science ID 000328575700121
View details for PubMedID 24514712
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Miniature fiber acoustic sensors using a photonic-crystal membrane
OPTICAL FIBER TECHNOLOGY
2013; 19 (6): 785-792
View details for DOI 10.1016/j.yofte.2013.07.009
View details for Web of Science ID 000328105600010
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Engineering-reflected phase in Fabry-Perot sensors with resonant mirrors
OPTICS LETTERS
2013; 38 (23): 4992-4995
Abstract
Fabry-Perot cavities made with photonic crystal (PC) mirrors and other resonant structures exhibit nontraditional characteristics due to the strong wavelength dependence of their reflected phase. This Letter describes how engineering the phase of PC mirrors enables sensors that are tolerant to variations in laser center frequency and line width. Reflection spectra measurements of Fabry-Perot cavities made with PC mirrors were collected as a function of wavelength and cavity length, providing experimental verification of theory and simulations.
View details for DOI 10.1364/OL.38.004992
View details for Web of Science ID 000327815100017
View details for PubMedID 24281492
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Fano resonances in integrated silicon Bragg reflectors for sensing applications
OPTICS EXPRESS
2013; 21 (22): 27209-27218
Abstract
We investigate theoretically and experimentally Fano resonances in integrated silicon Bragg reflectors. These asymmetric resonances are obtained by interference between light reflected from the Bragg waveguide and from the end facet. The Bragg reflectors were designed and modeled using the 1D transfer matrix method, and they were fabricated in standard silicon wafers using a CMOS-compatible process. The results show that the shape and asymmetry of the Fano resonances depend on the relative phase of the reflected light from the Bragg reflectors and end facet. This phase relationship can be controlled to optimize the lineshapes for sensing applications. Temperature sensing in these integrated Bragg reflectors are experimentally demonstrated with a temperature sensitivity of 77 pm/°C based on the thermo-optic effect of silicon.
View details for DOI 10.1364/OE.21.027209
View details for Web of Science ID 000327007800179
View details for PubMedID 24216944
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Finite-size limitations on Quality Factor of guided resonance modes in 2D Photonic Crystals
OPTICS EXPRESS
2013; 21 (20): 23640-23654
Abstract
High-Q guided resonance modes in two-dimensional photonic crystals, enable high field intensity in small volumes that can be exploited to realize high performance sensors. We show through simulations and experiments how the Q-factor of guided resonance modes varies with the size of the photonic crystal, and that this variation is due to loss caused by scattering of in-plane propagating modes at the lattice boundary and coupling of incident light to fully guided modes that exist in the homogeneous slab outside the lattice boundary. A photonic crystal with reflecting boundaries, realized by Bragg mirrors with a band gap for in-plane propagating modes, has been designed to suppress these edge effects. The new design represents a way around the fundamental limitation on Q-factors for guided resonances in finite photonic crystals. Results are presented for both simulated and fabricated structures.
View details for DOI 10.1364/OE.21.023640
View details for Web of Science ID 000325549800061
View details for PubMedID 24104276
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Time-Division-Multiplexed Interferometric Sensor Arrays
JOURNAL OF LIGHTWAVE TECHNOLOGY
2013; 31 (16): 3001-3008
View details for DOI 10.1109/JLT.2013.2272718
View details for Web of Science ID 000322145100001
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Short-cavity multimode fiber-tip Fabry-Perot sensors
OPTICS EXPRESS
2013; 21 (12): 14487-14499
Abstract
We make the case for minimizing cavity length of extrinsic Fabry-Pérot (FP) cavities for use in fiber-tip sensors. Doing so mitigates multiple challenges that arise from using multimode fibers: mode averaging, phase uncertainty, amplitude reduction, and spectral modal noise. We explore these effects in detail using modal simulations, and construct pressure sensors based on this principle. We discuss the multimodal effects that we observe in our fiber sensors, and use simple filtering of the spectral signal to more easily measure pressure sensitivity. The concept of short-cavity FP interferometry is important for ensuring high quality and performance of multimode fiber sensors.
View details for DOI 10.1364/OE.21.014487
View details for Web of Science ID 000320510300060
View details for PubMedID 23787637
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Two-axis MEMS scanner with transfer-printed high-reflectivity, broadband monolithic silicon photonic crystal mirrors
OPTICS EXPRESS
2013; 21 (11): 13800-13809
Abstract
We present a two-axis electrostatic MEMS scanner with high-reflectivity monolithic single-crystal-silicon photonic crystal (PC) mirrors suitable for applications in harsh environments. The reflective surfaces of the MEMS scanner are transfer-printed PC mirrors with low polarization dependence, low angular dependence, and reflectivity over 85% in the wavelength range of 1490nm~1505nm and above 90% over the wavelength band of 1550~1570nm. In static mode, the scanner has total scan range of 10.2° on one rotation axis and 7.8° on the other. Dynamic operation on resonance increase the scan range to 21° at 608Hz around the outer rotation axis and 9.5° at 1.73kHz about the inner rotation axis.
View details for DOI 10.1364/OE.21.013800
View details for Web of Science ID 000319814900085
View details for PubMedID 23736634
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High-Bandwidth AFM Probes for Imaging in Air and Fluid
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2013; 22 (3): 603-612
View details for DOI 10.1109/JMEMS.2012.2235822
View details for Web of Science ID 000319827700011
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Measurement of elastic properties in fluid using high bandwidth atomic force microscope probes
APPLIED PHYSICS LETTERS
2013; 102 (10)
View details for DOI 10.1063/1.4795598
View details for Web of Science ID 000316501200074
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MONOLITHIC SILICON WAVEGUIDES IN STANDARD SILICON
IEEE MICRO
2013; 33 (1): 32-40
View details for Web of Science ID 000315007400006
- Modeling and Demonstration of Thermally Stable High-Sensitivity Reproducible Acoustic Sensors Journal of Lightwave Technology 2013; 31 (16): 2701-2708
- Fano resonances in integrated silicon Bragg reflectors for sensing applications Optics Express 2013; 21 (22): 2720927219
- Single nano-particle sensing exploiting crossed polarizers to improve the signal-to-noise ratio 2013
- High-Reflectivity, Broadband Monolithic Silicon Photonic Crystal Mirrors on Two-Axis MEMS Scanner by Transfer-Printing 2013
- Engineering-reflected phase in Fabry–Perot sensors with resonant mirrors Optics Letters 2013; 38 (23): 4992–4995
- Detection of single nano-defects in photonic crystals between crossed polarizers Optics Express 2013; 21 (25): 31375–31389
- Monolithic Photonic Crystal-Based Fiber-TipFabry-Pérot Static Pressure Sensor 2013
- Short-cavity multimode fiber-tip Fabry-Pérot sensors Optics Express 2013; 21 (6): 14487–14499
- Double-layer silicon waveguides in standard silicon for 3D photonics 2013
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Modeling and Demonstration of Thermally Stable High-Sensitivity Reproducible Acoustic Sensors
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2012; 21 (6): 1347-1356
View details for DOI 10.1109/JMEMS.2012.2196494
View details for Web of Science ID 000311854500013
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Split-Frame Gimbaled Two-Dimensional MEMS Scanner for Miniature Dual-Axis Confocal Microendoscopes Fabricated by Front-Side Processing
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2012; 21 (2): 308-315
View details for DOI 10.1109/JMEMS.2011.2175368
View details for Web of Science ID 000302535800009
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Photonic-crystal membranes for optical detection of single nano-particles, designed for biosensor application
OPTICS EXPRESS
2012; 20 (7): 7954-7965
Abstract
A sensor designed to detect bio-molecules is presented. The sensor exploits a planar 2D photonic crystal (PC) membrane with sub-micron thickness and through holes, to induce high optical fields that allow detection of nano-particles smaller than the diffraction limit of an optical microscope. We report on our design and fabrication of a PC membrane with a nano-particle trapped inside. We have also designed and built an imaging system where an optical microscope and a CCD camera are used to take images of the PC membrane. Results show how the trapped nano-particle appears as a bright spot in the image. In a first experimental realization of the imaging system, single particles with a radius of 75 nm can be detected.
View details for Web of Science ID 000302138800107
View details for PubMedID 22453468
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Reflectivity and polarization dependence of polysilicon single-film broadband photonic crystal micro-mirrors
OPTICS EXPRESS
2012; 20 (6): 6306-6315
Abstract
We report on the fabrication of 2-D photonic crystal (PC) micro-mirrors, and Finite Difference Time Domain (FDTD) simulations and measurements of their reflectance spectra and polarization dependence at normal incidence. The PC mirrors were fabricated in free-standing thin polysilicon membranes supported by silicon nitride films for stress compensation. Greater than 90% reflectivity is measured over a wavelength range of 35 nm from 1565 nm to 1600 nm with small polarization dependence. Our FDTD simulations show that fabrication errors on the order of tens of nanometers can strongly affect the reflection spectra. When the fabrication errors are kept below this level, FDTD simulations on perfectly periodic structures accurately predict the reflection spectra of the fabricated PC mirrors, despite their sensitivity to the fabrication errors.
View details for Web of Science ID 000301877700077
View details for PubMedID 22418512
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In vivo near-infrared dual-axis confocal microendoscopy in the human lower gastrointestinal tract
JOURNAL OF BIOMEDICAL OPTICS
2012; 17 (2)
Abstract
Near-infrared confocal microendoscopy is a promising technique for deep in vivo imaging of tissues and can generate high-resolution cross-sectional images at the micron-scale. We demonstrate the use of a dual-axis confocal (DAC) near-infrared fluorescence microendoscope with a 5.5-mm outer diameter for obtaining clinical images of human colorectal mucosa. High-speed two-dimensional en face scanning was achieved through a microelectromechanical systems (MEMS) scanner while a micromotor was used for adjusting the axial focus. In vivo images of human patients are collected at 5 frames/sec with a field of view of 362×212 μm(2) and a maximum imaging depth of 140 μm. During routine endoscopy, indocyanine green (ICG) was topically applied a nonspecific optical contrasting agent to regions of the human colon. The DAC microendoscope was then used to obtain microanatomic images of the mucosa by detecting near-infrared fluorescence from ICG. These results suggest that DAC microendoscopy may have utility for visualizing the anatomical and, perhaps, functional changes associated with colorectal pathology for the early detection of colorectal cancer.
View details for DOI 10.1117/1.JBO.17.2.021102
View details for Web of Science ID 000303033600004
View details for PubMedID 22463020
View details for PubMedCentralID PMC3380818
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Tapping-mode force spectroscopy using cantilevers with interferometric high-bandwidth force sensors
APPLIED PHYSICS LETTERS
2012; 100 (5)
View details for DOI 10.1063/1.3679683
View details for Web of Science ID 000300065300065
- OvercomingMultimodal Effects in Optical Fiber Tip CMOS-Compatible Fabry-Perot Sensors 2012
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Enhanced scattering from nano-particles trapped in photonic crystal membranes
International Conference on Optical MEMS and Nanophotonics (OMN)
IEEE. 2012: 21–22
View details for Web of Science ID 000309942400011
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Asymmetric Fano Lineshapes in Integrated Silicon Bragg Reflectors
Conference on Lasers and Electro-Optics (CLEO)
IEEE. 2012
View details for Web of Science ID 000310362402339
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9.6-mm diameter femtosecond laser microsurgery probe
Conference on Lasers and Electro-Optics (CLEO)
IEEE. 2012
View details for Web of Science ID 000310362400003
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Double-Layer Silicon Photonic Crystal Fiber Tip Temperature Sensor
25th IEEE Photonics Conference (IPC)
IEEE. 2012: 550–551
View details for Web of Science ID 000312865000274
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Overcoming Multimodal Effects in Optical Fiber Tip CMOS-Compatible Fabry-Perot Sensors
Conference on Lasers and Electro-Optics (CLEO)
IEEE. 2012
View details for Web of Science ID 000310362402186
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Interdigitated Annular CMUT Arrays for Ultrasound Assisted Delivery of Fluorescent Contrast Agents
IEEE International Ultrasonics Symposium (IUS)
IEEE. 2012: 96–99
View details for Web of Science ID 000309918400024
- Ratiometric Molecular Microscopy: Towards Real-Time Quantitative Delineation of Brain Tumor Margins 2012
- Multifunctional Fiber Sensors Based on Photonic Crystals 2012
- Integrated Silicon Photonic Temperature Sensors Based onBragg Reflectors with Asymmetric Fano Lineshapes 2012
- Optical imaging system designed for biomolecule detection using photonic crystal membranes 2012
- Asymmetric Fano Lineshapes in Integrated Silicon Bragg Reflectors 2012
- Double-Layer Silicon Photonic Crystal Fiber Tip Temperature Sensor 2012
- 9.6mm diameter femtosecond laser microsurgeryprobe 2012
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Photonic Crystal Fiber Tip Sensor for High-Temperature Measurement
IEEE SENSORS JOURNAL
2011; 11 (11): 2643-2648
View details for DOI 10.1109/JSEN.2011.2153844
View details for Web of Science ID 000304162300004
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Multilayered Monolithic Silicon Photonic Crystals
IEEE PHOTONICS TECHNOLOGY LETTERS
2011; 23 (11): 730-732
View details for DOI 10.1109/LPT.2011.2132698
View details for Web of Science ID 000290629800008
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High-Resolution Nanomechanical Mapping Using Interferometric-Force-Sensing AFM Probes
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2011; 20 (3): 654-664
View details for DOI 10.1109/JMEMS.2011.2127452
View details for Web of Science ID 000291316000015
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Optical design and imaging performance testing of a 9.6-mm diameter femtosecond laser microsurgery probe
OPTICS EXPRESS
2011; 19 (11): 10536-10552
Abstract
We present the optical design of a 9.6-mm diameter fiber-coupled probe for combined femtosecond laser microsurgery and nonlinear optical imaging. Towards enabling clinical use, we successfully reduced the dimensions of our earlier 18-mm microsurgery probe by half, while improving optical performance. We use analytical and computational models to optimize the miniaturized lens system for off-axis scanning aberrations. The optimization reveals that the optical system can be aberration-corrected using simple aspheric relay lenses to achieve diffraction-limited imaging resolution over a large field of view. Before moving forward with custom lenses, we have constructed the 9.6-mm probe using off-the-shelf spherical relay lenses and a 0.55 NA aspheric objective lens. In addition to reducing the diameter by nearly 50% and the total volume by 5 times, we also demonstrate improved lateral and axial resolutions of 1.27 µm and 13.5 µm, respectively, compared to 1.64 µm and 16.4 µm in our previous work. Using this probe, we can successfully image various tissue samples, such as rat tail tendon that required 2-3 × lower laser power than the current state-of-the-art. With further development, image-guided, femtosecond laser microsurgical probes such as this one can enable physicians to achieve the highest level of surgical precision anywhere inside the body.
View details for Web of Science ID 000290852800048
View details for PubMedID 21643308
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In Vivo Imaging of Human and Mouse Skin with a Handheld Dual-Axis Confocal Fluorescence Microscope
JOURNAL OF INVESTIGATIVE DERMATOLOGY
2011; 131 (5): 1061-1066
Abstract
Advancing molecular therapies for the treatment of skin diseases will require the development of new tools that can reveal spatiotemporal changes in the microanatomy of the skin and associate these changes with the presence of the therapeutic agent. For this purpose, we evaluated a handheld dual-axis confocal (DAC) microscope that is capable of in vivo fluorescence imaging of skin, using both mouse models and human skin. Individual keratinocytes in the epidermis were observed in three-dimensional image stacks after topical administration of near-infrared (NIR) dyes as contrast agents. This suggested that the DAC microscope may have utility in assessing the clinical effects of a small interfering RNA (siRNA)-based therapeutic (TD101) that targets the causative mutation in pachyonychia congenita (PC) patients. The data indicated that (1) formulated indocyanine green (ICG) readily penetrated hyperkeratotic PC skin and normal callused regions compared with nonaffected areas, and (2) TD101-treated PC skin revealed changes in tissue morphology, consistent with reversion to nonaffected skin compared with vehicle-treated skin. In addition, siRNA was conjugated to NIR dye and shown to penetrate through the stratum corneum barrier when topically applied to mouse skin. These results suggest that in vivo confocal microscopy may provide an informative clinical end point to evaluate the efficacy of experimental molecular therapeutics.
View details for DOI 10.1038/jid.2010.401
View details for Web of Science ID 000289789900014
View details for PubMedID 21191407
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Highly Sensitive Monolithic Silicon Photonic Crystal Fiber Tip Sensor for Simultaneous Measurement of Refractive Index and Temperature
JOURNAL OF LIGHTWAVE TECHNOLOGY
2011; 29 (9): 1367-1374
View details for DOI 10.1109/JLT.2011.2126018
View details for Web of Science ID 000289802300007
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Miniature photonic-crystal hydrophone optimized for ocean acoustics
JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA
2011; 129 (4): 1837-1850
Abstract
This work reports on an optical hydrophone that is insensitive to hydrostatic pressure, yet capable of measuring acoustic pressures as low as the background noise in the ocean in a frequency range of 1 Hz to 100 kHz. The miniature hydrophone consists of a Fabry-Perot interferometer made of a photonic-crystal reflector interrogated with a single-mode fiber and is compatible with existing fiber-optic technologies. Three sensors with different acoustic power ranges placed within a sub-wavelength sized hydrophone head allow a high dynamic range in the excess of 160 dB with a low harmonic distortion of better than -30 dB. A method for suppressing cross-coupling between sensors in the same hydrophone head is also proposed. A prototype was fabricated, assembled, and tested. The sensitivity was measured from 100 Hz to 100 kHz, demonstrating a sound-pressure-equivalent noise spectral density down to 12 μPa/Hz(1/2), a flatband wider than 10 kHz, and very low distortion.
View details for DOI 10.1121/1.3543949
View details for Web of Science ID 000289298600026
View details for PubMedID 21476640
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Modeling, design, and analysis of interferometric cantilevers for time-resolved force measurements in tapping-mode atomic force microscopy
JOURNAL OF APPLIED PHYSICS
2011; 109 (6)
View details for DOI 10.1063/1.3553852
View details for Web of Science ID 000289149900122
- High resolution nanomechanical mapping using interferometric-force-sensing AFM probes Journal of Microelectromechanical Systems 2011; 20 (3): 654-664
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Fabry-Perot Fiber Sensors with Reproducible Displacement Sensitivities
16th International Conference on Optical MEMS and Nanophotonics (OMN)
IEEE. 2011: 191–192
View details for Web of Science ID 000297850100081
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3-D MEMS Scanning System For Dual-Axis Confocal Microendoscopy
16th International Conference on Optical MEMS and Nanophotonics (OMN)
IEEE. 2011: 71–72
View details for Web of Science ID 000297850100029
- 3-D MEMS Scanning System For Dual-Axis Confocal Microendoscopy 2011
- Time-Resolved Tapping-Mode Atomic Force Microscopy Scanning Probe Microscopy in Nanoscience and Nanotechnology 2 Springer Verlag. 2011: 1
- Fabry-Perot Fiber Sensors with Reproducible Displacement Sensitivities 2011
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Double-Layer Silicon Photonic Crystal Fiber Tip Sensor
16th International Conference on Optical MEMS and Nanophotonics (OMN)
IEEE. 2011: 97–98
View details for Web of Science ID 000297850100040
- Spot Formation and Scanning Microscopy via Multimode Fibers 2011
- Frontside-only processing of 2-D MEMS scanner for miniature dual-axis confocal microendoscopes 2011
- Double-Layer Silicon Photonic Crystal Fiber Tip Sensor 2011
- Interdigitated Annular CMUT Arrays for Ultrasound Assisted Delivery of Fluorescent Contrast Agents 2011
- AGILE: Axially Graded Index LEns as a non-tracking solar concentrator 2011
- Cortial blood flow imaging with a portable MEMS based2-photon fluorescence microendoscope 2011
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Amplified spontaneous emission rejection with multi-functional MEMS tunable filter
ELECTRONICS LETTERS
2010; 46 (18): 1275-U57
View details for DOI 10.1049/el.2010.0957
View details for Web of Science ID 000281693800022
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Miniaturization of free space optical systems
APPLIED OPTICS
2010; 49 (25): F18-F31
Abstract
Coherent illumination enables not only integrated optics, but also miniaturized free-space optics that takes advantage of the amplitude and phase control afforded by optical microelectromechanical systems (MEMS) and photonic crystals. These technologies also provide a practical and cost-effective means for integration and packaging of optical systems. The properties of miniaturized optical systems based on optical MEMS and photonic crystals are described, and efficient analysis and design approaches to miniaturized optical scanners and tunable diffractive optical elements are demonstrated. The impact of photonic crystals on free-space micro-optics is discussed.
View details for Web of Science ID 000281748100025
View details for PubMedID 20820200
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Displacement Sensing With a Mechanically Tunable Photonic Crystal
IEEE PHOTONICS TECHNOLOGY LETTERS
2010; 22 (16): 1196-1198
View details for DOI 10.1109/LPT.2010.2050584
View details for Web of Science ID 000283537800004
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Photonic Components for Future Fiber Access Networks
IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS
2010; 28 (6): 928-935
View details for DOI 10.1109/JSAC.2010.100816
View details for Web of Science ID 000283383600016
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Multifunctional Tunable Optical Filter Using MEMS Spatial Light Modulator
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2010; 19 (3): 610-618
View details for DOI 10.1109/JMEMS.2010.2043641
View details for Web of Science ID 000278537900018
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Assessing delivery and quantifying efficacy of small interfering ribonucleic acid therapeutics in the skin using a dual-axis confocal microscope
JOURNAL OF BIOMEDICAL OPTICS
2010; 15 (3)
Abstract
Transgenic reporter mice and advances in imaging instrumentation are enabling real-time visualization of cellular mechanisms in living subjects and accelerating the development of novel therapies. Innovative confocal microscope designs are improving their utility for microscopic imaging of fluorescent reporters in living animals. We develop dual-axis confocal (DAC) microscopes for such in vivo studies and create mouse models where fluorescent proteins are expressed in the skin for the purpose of advancing skin therapeutics and transdermal delivery tools. Three-dimensional image volumes, through the different skin compartments of the epidermis and dermis, can be acquired in several seconds with the DAC microscope in living mice, and are comparable to histologic analyses of reporter protein expression patterns in skin sections. Intravital imaging with the DAC microscope further enables visualization of green fluorescent protein (GFP) reporter gene expression in the skin over time, and quantification of transdermal delivery of small interfering RNA (siRNA) and therapeutic efficacy. Visualization of transdermal delivery of nucleic acids will play an important role in the development of innovative strategies for treating skin pathologies.
View details for DOI 10.1117/1.3432627
View details for Web of Science ID 000280642900042
View details for PubMedID 20615029
View details for PubMedCentralID PMC2904026
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Micromirror-scanned dual-axis confocal microscope utilizing a gradient-index relay lens for image guidance during brain surgery
JOURNAL OF BIOMEDICAL OPTICS
2010; 15 (2)
Abstract
A fluorescence confocal microscope incorporating a 1.8-mm-diam gradient-index relay lens is developed for in vivo histological guidance during resection of brain tumors. The microscope utilizes a dual-axis confocal architecture to efficiently reject out-of-focus light for high-contrast optical sectioning. A biaxial microelectromechanical system (MEMS) scanning mirror is actuated at resonance along each axis to achieve a large field of view with low-voltage waveforms. The unstable Lissajous scan, which results from actuating the orthogonal axes of the MEMS mirror at highly disparate resonance frequencies, is optimized to fully sample 500x500 pixels at two frames per second. Optically sectioned fluorescence images of brain tissues are obtained in living mice to demonstrate the utility of this microscope for image-guided resections.
View details for DOI 10.1117/1.3386055
View details for Web of Science ID 000278465300060
View details for PubMedID 20459274
View details for PubMedCentralID PMC2869369
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Two-Dimensional Photonic Crystals Fabricated in Monolithic Single-Crystal Silicon
IEEE PHOTONICS TECHNOLOGY LETTERS
2010; 22 (2): 67-69
View details for DOI 10.1109/LPT.2009.2036143
View details for Web of Science ID 000273091000001
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Asymmetrical Spectral Response in Fiber Fabry-Perot Interferometers (vol 27, pg 5648, 2009)
JOURNAL OF LIGHTWAVE TECHNOLOGY
2010; 28 (1): 188-188
View details for DOI 10.1109/JLT.2009.2039364
View details for Web of Science ID 000273569000001
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High Temperature Photonic Crystal Fiber Tip Sensor
2010 IEEE Sensors Conference
IEEE. 2010: 970–974
View details for Web of Science ID 000287982100215
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Monolithic Silicon Photonic Crystal Fiber Tip Sensor for Refractive Index and Temperature Sensing
Conference on Lasers and Electro-Optics (CLEO)/Quantum Electronics and Laser Science Conference (QELS)
IEEE. 2010
View details for Web of Science ID 000290513600412
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High-Sensitivity Thermally Stable Acoustic Fiber Sensor
2010 IEEE Sensors Conference
IEEE. 2010: 1148–1151
View details for Web of Science ID 000287982100253
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Quasi-Passive and Reconfigurable Node for Optical Access Network
Conference on Lasers and Electro-Optics (CLEO)/Quantum Electronics and Laser Science Conference (QELS)
IEEE. 2010
View details for Web of Science ID 000290513601076
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Surgical dual-axis confocal microscope for brain tumor resection
IEEE Photonics Society Winter Topicals Meeting Series
IEEE. 2010: 76–77
View details for Web of Science ID 000283803700040
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From Bench to Bedside with Advanced Confocal Microendoscope
IEEE Photonics Society Winter Topicals Meeting Series
IEEE. 2010: 83–84
View details for Web of Science ID 000283803700044
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From Bench to Bedside with Advanced Dual-Axes Confocal Microendoscope
23rd IEEE International Conference on Micro Electro Mechanical Systems (MEMS 2010)
IEEE. 2010: 27–30
View details for Web of Science ID 000278416400005
- A surgical confocal microscope utilizing a MEMS scanner and a GRIN relay lens for molecular image-guided brain tumor resection 2010
- Photonic Crystal Mirrors for Free-Space Communication and Fiber-Optic Sensors 2010
- Quasi-Passive and Reconfigurable Node for Optical Access Network 2010
- From Bench to Bedside with AdvancedDual-Axes Confocal Microendoscope 2010
- Miniature optical-sectioning microscopy for molecular image guidance during brain tumor resection 2010
- High Temperature Photonic Crystal Fiber Tip Sensor 2010
- From Bench to Bedside with AdvancedDual-Axes Confocal Microendoscope 2010
- High-Sensitivity Thermally Stable Acoustic Fiber Sensor 2010
- SurgicalDual-Axis Confocal Microscope for Brain Tumor Resection 2010
- Monolithic Silicon Photonic Crystal Fiber Tip Sensor forRefractive Index and Temperature Sensing 2010
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Asymmetrical Spectral Response in Fiber Fabry-Perot Interferometers
JOURNAL OF LIGHTWAVE TECHNOLOGY
2009; 27 (24): 5648-5656
View details for DOI 10.1109/JLT.2009.2032135
View details for Web of Science ID 000272479900001
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A Large-Area High-Reflectivity Broadband Monolithic Single-Crystal-Silicon Photonic Crystal Mirror MEMS Scanner With Low Dependence on Incident Angle and Polarization
IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS
2009; 15 (5): 1447-1454
View details for DOI 10.1109/JSTQE.2009.2021863
View details for Web of Science ID 000270950300023
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3-D Near-Infrared Fluorescence Imaging Using an MEMS-Based Miniature Dual-Axis Confocal Microscope
IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS
2009; 15 (5): 1344-1350
View details for DOI 10.1109/JSTQE.2009.2021533
View details for Web of Science ID 000270950300008
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Introduction to the Issue on Nanophotonics and Optical MEMS
IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS
2009; 15 (5): 1307-1309
View details for DOI 10.1109/JSTQE.2009.2024388
View details for Web of Science ID 000270950300001
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High-Reflectivity Broadband Photonic Crystal Mirror MEMS Scanner With Low Dependence on Incident Angle and Polarization
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2009; 18 (4): 924-932
View details for DOI 10.1109/JMEMS.2009.2021814
View details for Web of Science ID 000268641700018
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siRNA silencing of keratinocyte-specific GFP expression in a transgenic mouse skin model
GENE THERAPY
2009; 16 (8): 963-972
Abstract
Small interfering RNAs (siRNAs) can be designed to specifically and potently target and silence a mutant allele, with little or no effect on the corresponding wild-type allele expression, presenting an opportunity for therapeutic intervention. Although several siRNAs have entered clinical trials, the development of siRNA therapeutics as a new drug class will require the development of improved delivery technologies. In this study, a reporter mouse model (transgenic click beetle luciferase/humanized monster green fluorescent protein) was developed to enable the study of siRNA delivery to skin; in this transgenic mouse, green fluorescent protein reporter gene expression is confined to the epidermis. Intradermal injection of siRNAs targeting the reporter gene resulted in marked reduction of green fluorescent protein expression in the localized treatment areas as measured by histology, real-time quantitative polymerase chain reaction and intravital imaging using a dual-axes confocal fluorescence microscope. These results indicate that this transgenic mouse skin model, coupled with in vivo imaging, will be useful for development of efficient and 'patient-friendly' siRNA delivery techniques and should facilitate the translation of siRNA-based therapeutics to the clinic for treatment of skin disorders.
View details for DOI 10.1038/gt.2009.62
View details for Web of Science ID 000268916800004
View details for PubMedID 19474811
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In vivo brain imaging using a portable 2.9 g two-photon microscope based on a microelectromechanical systems scanning mirror
OPTICS LETTERS
2009; 34 (15): 2309-2311
Abstract
We present a two-photon microscope that is approximately 2.9 g in mass and 2.0 x 1.9 x 1.1 cm(3) in size and based on a microelectromechanical systems (MEMS) laser-scanning mirror. The microscope has a focusing motor and a micro-optical assembly composed of four gradient refractive index lenses and a dichroic microprism. Fluorescence is captured without the detected emissions reflecting off the MEMS mirror, by use of separate optical fibers for fluorescence collection and delivery of ultrashort excitation pulses. Using this microscope we imaged neocortical microvasculature and tracked the flow of erythrocytes in live mice.
View details for Web of Science ID 000269405900022
View details for PubMedID 19649080
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Vertical Mirror Fabrication Combining KOH Etch and DRIE of (110) Silicon
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2009; 18 (1): 217-227
View details for DOI 10.1109/JMEMS.2008.2009840
View details for Web of Science ID 000263123100022
- Higher harmonics and time-varying force detection in dynamic force microscopy Handbook of Nanotechnology Springer Verlag. 2009; 3: 1
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Photonic Crystal Fiber Tip Sensor for Precision Temperature Sensing
22nd Annual Meeting of the IEEE-Photonics-Society
IEEE. 2009: 761–762
View details for Web of Science ID 000279577600388
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Sequential in vivo Molecular Imaging with a Dual-Axes Confocal Microscope
Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference (CLEO/QELS 2009)
IEEE. 2009: 1–2
View details for Web of Science ID 000274751300001
- A CMOS Compatible Low Temperature Process for Photonic CrystalMEMS Scanner 2009
- Optomechanical fiber gyroscope 2009
- Photonic Crystal Fiber Tip Sensorfor Precision Temperature Sensing 2009
- In vivo Clinical and Intravital Imaging with MEMS Based Dual-Axes Confocal Microscopes 2009
- Tunable Optical Bandpass Filter with High-Quality Vertical MirrorsMicroassembled on Movable MEMS Platforms 2009
- Sequential in vivo Molecular Imaging with a Dual-Axes Confocal Microscope 2009
- Monolithic Silicon Photonic Crystal Slab Fiber Tip Sensor 2009
- Interferometric Force Sensing AFM Probes ForNanomechanical Mapping of Material Properties 2009
- Fiber-Optical Acoustic Sensor Based on a Photonic-Crystal Diaphragm 2009
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Analysis of guided-resonance-based polarization beam splitting in photonic crystal slabs
JOURNAL OF THE OPTICAL SOCIETY OF AMERICA A-OPTICS IMAGE SCIENCE AND VISION
2008; 25 (11): 2680-2692
Abstract
We present an analysis of the phase and amplitude responses of guided resonances in a photonic crystal slab. Through this analysis, we obtain the general rules and conditions under which a photonic crystal slab can be employed as a general elliptical polarization beam splitter, separating an incoming beam equally into its two orthogonal constituents, so that half the power is reflected in one polarization state, and half the power is transmitted in the other state. We show that at normal incidence a photonic crystal slab acts as a dual quarter-wave retarder in which the fast and slow axes are switched for reflection and transmission. We also analyze the case where such a structure operates at oblique incidences. As a result we show that the effective dielectric constant of the photonic crystal slab imposes the Brewster angle as a boundary, separating two ranges of angles with different mechanisms of polarization beam splitting. We show that the diattenuation can be tuned from zero to one to make the structure a circular or linear polarization beam splitter. We verify our analytical analysis through finite-difference time-domain simulations and experimental measurements at infrared wavelengths.
View details for Web of Science ID 000261520700008
View details for PubMedID 18978845
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Pull-In Analysis of Torsional Scanners Actuated by Electrostatic Vertical Combdrives
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2008; 17 (5): 1228-1238
View details for DOI 10.1109/JMEMS.2008.2004824
View details for Web of Science ID 000260464800019
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Controlling uncoupled resonances in photonic crystals through breaking the mirror symmetry
OPTICS EXPRESS
2008; 16 (17): 13090-13103
Abstract
We show that modes in a photonic crystal slab that are uncoupled to outside radiation in a symmetric structure can be excited by breaking the mirror symmetry through introducing a protrusion on the side of the photonic crystal holes. We show that coupling to these resonances can be controlled by the strength of this asymmetry, and that it is also possible to choose among modes to couple to, through the shape of the asymmetry introduced. We provide simple theoretical arguments that explain the effect, and present eigenmode simulations and time-domain simulations. We confirm this predicted behavior with measurements on a photonic crystal with a broken mirror symmetry that exhibits an additional sharp resonant feature with a linewidth of 0.5 nm, in agreement with both calculated and simulated predictions.
View details for Web of Science ID 000259268700070
View details for PubMedID 18711548
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Cantilevers with integrated sensor for time-resolved force measurement in tapping-mode atomic force microscopy
APPLIED PHYSICS LETTERS
2008; 93 (2)
View details for DOI 10.1063/1.2959828
View details for Web of Science ID 000257796100091
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Miniaturized probe for femtosecond laser microsurgery and two-photon imaging
OPTICS EXPRESS
2008; 16 (13): 9996-10005
Abstract
Combined two-photon fluorescence microscopy and femtosecond laser microsurgery has many potential biomedical applications as a powerful "seek-and-treat" tool. Towards developing such a tool, we demonstrate a miniaturized probe which combines these techniques in a compact housing. The device is 10 x 15 x 40 mm(3) in size and uses an aircore photonic crystal fiber to deliver femtosecond laser pulses at 80 MHz repetition rate for imaging and 1 kHz for microsurgery. A fast two-axis microelectromechanical system scanning mirror is driven at resonance to produce Lissajous beam scanning at 10 frames per second. Field of view is 310 microm in diameter and the lateral and axial resolutions are 1.64 microm and 16.4 microm, respectively. Combined imaging and microsurgery is demonstrated using live cancer cells.
View details for Web of Science ID 000257563900082
View details for PubMedID 18575570
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Three-dimensional in vivo imaging by a handheld dual-axes confocal microscope
OPTICS EXPRESS
2008; 16 (10): 7224-7232
Abstract
We present a handheld dual-axes confocal microscope that is based on a two-dimensional microelectromechanical systems (MEMS) scanner. It performs reflectance and fluorescence imaging at 488 nm wavelength, with three-dimensional imaging capability. The fully packaged microscope has a diameter of 10 mm and acquires images at 4 Hz frame rate with a maximum field of view of 400 microm x 260 microm. The transverse and axial resolutions of the handheld probe are 1.7 microm and 5.8 microm, respectively. Capability to perform real time small animal imaging is demonstrated in vivo in transgenic mice.
View details for Web of Science ID 000256469800048
View details for PubMedID 18545427
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Scalable optical switches with large port count based on a waveguide grating router and passive couplers
IEEE PHOTONICS TECHNOLOGY LETTERS
2008; 20 (5-8): 508-510
View details for DOI 10.1109/LPT.2008.918237
View details for Web of Science ID 000257952800061
- Micro and Nano Electromechanical Systems National Nanotechnology Infrastructure Network (NNIN) Open Textbook on Nanotechnology (33 pages), http://www.nano.umn.edu/nnin_opentext/contents.jsp 2008: 1
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Large-Area High-Reflectivity Broadband Monolithic Silicon Photonic Crystal Mirror MEMS Scanner
IEEE/LEOS International Conference on Optical MEMS and Nanophotonics
IEEE. 2008: 76–77
View details for Web of Science ID 000264556700039
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Large-Area Monolithic Photonic Crystal Mirrors with High Reflectivity in the 1250-1650nm Band Patterned by Optical Lithography
IEEE/LEOS International Conference on Optical MEMS and Nanophotonics
IEEE. 2008: 86–87
View details for Web of Science ID 000264556700044
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Two-Photon Luminescence Imaging Using a MEMS-Based Miniaturized Probe
Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference (CLEO/QELS 2008)
IEEE. 2008: 951–952
View details for Web of Science ID 000260498400477
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Photonic-crystal-diaphragm-based fiber-tip hydrophone optimized for ocean acoustics
19th International Conference on Optical Fibre Sensors
SPIE-INT SOC OPTICAL ENGINEERING. 2008
View details for DOI 10.1117/12.785919
View details for Web of Science ID 000258398100003
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Double-layered Monolithic Silicon Photonic Crystals
Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference (CLEO/QELS 2008)
IEEE. 2008: 857–858
View details for Web of Science ID 000260498400430
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Interface Quality Control of Monolithic Photonic Crystals by Hydrogen Annealing
Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference (CLEO/QELS 2008)
IEEE. 2008: 316–317
View details for Web of Science ID 000260498400159
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MEMS based Dual-Axes Confocal Clinical Endoscope for Real Time in vivo Imaging
IEEE/LEOS International Conference on Optical MEMS and Nanophotonics
IEEE. 2008: 42–43
View details for Web of Science ID 000264556700022
- Three-dimensional in-vivo imaging with a miniature dual-axes confocal fluorescence microscope 2008
- Double-layered Monolithic Silicon Photonic Crystals 2008
- Large-Area Monolithic Photonic Crystal Mirrors with High Reflectivity in the 1250-1650nm Band Patterned by Optical Lithography 2008
- Microelectromechanical Systems for Lightwave Communication Optical Fiber Telecommunications, A: Components and Subsystems edited by Kaminow, I., P., Li, T., Willner, A., E. Academic Press. 2008: 713–758
- Displacement sensing with a mechanically tunable photonic crystal 2008
- Monolithic photonic crystals 2008
- Two-Photon Luminescence Imaging Using a MEMS-Based Miniaturized Probe 2008
- Interface Quality Control of Monolithic Photonic Crystals by Hydrogen Annealing 2008
- MEMS based Dual-Axes Confocal Clinical Endoscope for Real Time in vivo Imaging 2008
- Photonic Microsystems - Micro and Nanotechnology Applied to Optical Devices and Systems Springer Verlag. 2008
- In vivo Intravital Imaging with a Dual-Axes Confocal Microscope in Skin 2008
- Large-Area High-Reflectivity Broadband Monolithic Silicon Photonic Crystal Mirror MEMS Scanner 2008
- Photonic-crystal-diaphragm-based fiber-tip hydrophone optimized for ocean acoustics 2008
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Reconfigurable optical wavelength multiplexer using a MEMS tunable blazed grating
JOURNAL OF LIGHTWAVE TECHNOLOGY
2007; 25 (10): 3100-3107
View details for DOI 10.1109/JLT.2007.904427
View details for Web of Science ID 000250846000027
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External fibre Fabry-Perot acoustic sensor based on a photonic-crystal mirror
18th International Conference on Optical Fibre Sensors
IOP PUBLISHING LTD. 2007: 3049–54
View details for DOI 10.1088/0957-0233/18/10/S01
View details for Web of Science ID 000249982100002
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An atomic force microscope tip designed to measure time-varying nanomechanical forces
NATURE NANOTECHNOLOGY
2007; 2 (8): 507-514
Abstract
Tapping-mode atomic force microscopy (AFM), in which the vibrating tip periodically approaches, interacts and retracts from the sample surface, is the most common AFM imaging method. The tip experiences attractive and repulsive forces that depend on the chemical and mechanical properties of the sample, yet conventional AFM tips are limited in their ability to resolve these time-varying forces. We have created a specially designed cantilever tip that allows these interaction forces to be measured with good (sub-microsecond) temporal resolution and material properties to be determined and mapped in detail with nanoscale spatial resolution. Mechanical measurements based on these force waveforms are provided at a rate of 4 kHz. The forces and contact areas encountered in these measurements are orders of magnitude smaller than conventional indentation and AFM-based indentation techniques that typically provide data rates around 1 Hz. We use this tool to quantify and map nanomechanical changes in a binary polymer blend in the vicinity of its glass transition.
View details for DOI 10.1038/nnano.2007.226
View details for Web of Science ID 000249062900016
View details for PubMedID 18654349
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Two-dimensional MEMS scanner for dual-axes confocal microscopy
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2007; 16 (4): 969-976
View details for DOI 10.1109/JMEMS.2007.892900
View details for Web of Science ID 000248578700021
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Fiber-optic confocal microscope using a MEMS scanner and miniature objective lens
OPTICS EXPRESS
2007; 15 (15): 9113-9122
Abstract
We designed and constructed a single-fiber-optic confocal microscope (SFCM) with a microelectromechanical system (MEMS) scanner and a miniature objective lens. Axial and lateral resolution values for the system were experimentally measured to be 9.55 mum and 0.83 mum respectively, in good agreement with theoretical predictions. Reflectance images were acquired at a rate of 8 frames per second, over a 140 mum x 70 mum field-of-view. In anticipation of future applications in oral cancer detection, we imaged ex vivo and in vivo human oral tissue with the SFCM, demonstrating the ability of the system to resolve cellular detail.
View details for Web of Science ID 000248394500002
View details for PubMedID 19547251
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Introduction to the issue on optical micro- and nanosystems
IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS
2007; 13 (2): 145-146
View details for DOI 10.1109/JSTQE.2007.894188
View details for Web of Science ID 000246123200001
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Optical pattern generation using a, spatial light modulator for maskless lithography
IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS
2007; 13 (2): 147-154
View details for DOI 10.1109/JSTQE.2006.893095
View details for Web of Science ID 000246123200002
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Single-crystal-silicon continuous membrane deformable mirror array for adaptive optics in space-based telescopes
IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS
2007; 13 (2): 162-167
View details for DOI 10.1109/JSTQE.2007.893560
View details for Web of Science ID 000246123200004
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Superresolution digital image enhancement by subpixel image translation with a scanning micromirror
IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS
2007; 13 (2): 304-311
View details for DOI 10.1109/JSTQE.2006.893110
View details for Web of Science ID 000246123200023
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Miniature near-infrared dual-axes confocal microscope utilizing a two-dimensional microelectromechanical systems scanner
OPTICS LETTERS
2007; 32 (3): 256-258
Abstract
The first, to our knowledge, miniature dual-axes confocal microscope has been developed, with an outer diameter of 10 mm, for subsurface imaging of biological tissues with 5-7 microm resolution. Depth-resolved en face images are obtained at 30 frames per second, with a field of view of 800 x 100 microm, by employing a two-dimensional scanning microelectromechanical systems mirror. Reflectance and fluorescence images are obtained with a laser source at 785 nm, demonstrating the ability to perform real-time optical biopsy.
View details for Web of Science ID 000244278900018
View details for PubMedID 17215937
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Portable forms of fiber-optic one- and two-photon fluorescence microendoseopy towards imaging in freely moving mice
51st Annual Meeting of the Biophysical-Society
CELL PRESS. 2007: 154A–154A
View details for Web of Science ID 000243972400714
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A portable two-photon fluorescence microendoscope based on a two-dimensional scanning mirror
IEEE/LEOS International Conference on Optical MEMS and Nanophotonics
IEEE. 2007: 6–7
View details for Web of Science ID 000251224200004
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An external cavity tunable laser with a low-loss narrowband MEMS tunable blazed grating
20th Annual Meeting of the IEEE-Lasers-and-Electro-Optics-Society
IEEE. 2007: 834–835
View details for Web of Science ID 000259345200418
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Vortex generation and pixel calibration using a spatial light modulator for maskless lithography
IEEE/LEOS International Conference on Optical MEMS and Nanophotonics
IEEE. 2007: 147–148
View details for Web of Science ID 000251224200072
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Pull-in analysis of scanners actuated by electrostatic vertical combdrives
IEEE/LEOS International Conference on Optical MEMS and Nanophotonics
IEEE. 2007: 85–86
View details for Web of Science ID 000251224200043
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Displacement sensing with a mechanically tunable photonic crystal
20th Annual Meeting of the IEEE-Lasers-and-Electro-Optics-Society
IEEE. 2007: 345–346
View details for Web of Science ID 000259345200170
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Large-stroke self-aligned vertical comb drive actuated micromirror arrays for adaptive optics applications
Conference on MEMS Adaptive Optics
SPIE-INT SOC OPTICAL ENGINEERING. 2007
View details for DOI 10.1117/12.710894
View details for Web of Science ID 000246079300025
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Monolithic photonic crystals
20th Annual Meeting of the IEEE-Lasers-and-Electro-Optics-Society
IEEE. 2007: 341–342
View details for Web of Science ID 000259345200168
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Reflectance and fluorescence imaging with a MEMS dual-axes confocal microscope
Conference on MOEMS and Miniaturized Systems VI
SPIE-INT SOC OPTICAL ENGINEERING. 2007
View details for DOI 10.1117/12.711560
View details for Web of Science ID 000245835900015
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Three-dimensional In vivo real time imaging by a miniature dual-axes confocal microscope based on a two-dimensional mems scanner
14th International Conference on Solid-State Sensors, Actuators and Microsystems/21st European Conference on Solid-State Transducers
IEEE. 2007
View details for Web of Science ID 000249603700105
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Single-film Broadband Photonic Crystal Micro-mirror with Large Angular Range and Low Polarization Dependence
Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference
IEEE. 2007: 1255–1256
View details for Web of Science ID 000268751001067
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High reflectivity broadband photonic crystal mirror MEMS scanner
14th International Conference on Solid-State Sensors, Actuators and Microsystems/21st European Conference on Solid-State Transducers
IEEE. 2007
View details for Web of Science ID 000249603700375
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Compact optical design for dual-axes confocal endoscopic microscopes
Conference on Three-Dimensional and Multidimensional Microscopy - Image Acquisition and Processing XIV
SPIE-INT SOC OPTICAL ENGINEERING. 2007
View details for DOI 10.1117/12.699484
View details for Web of Science ID 000245855700007
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Three-Dimensional in vivo Reflectance and Fluorescence Imaging by a Handheld Dual-Axes Confocal Microscope
Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference
IEEE. 2007: 795–796
View details for Web of Science ID 000268751000400
- Reflectance and fluorescence imaging with a MEMS dual-axes confocal microscope (invited talk) 2007
- Three-Dimensional in vivo Reflectance and Fluorescence Imaging by a Handheld Dual-Axes Confocal Microscope 2007
- A compact 15-mm wide two-photon microscope for imaging and femtosecond laser microsurgery 2007
- A Portable Two-photon Fluorescence Microendoscope Based on a Two-dimensional Scanning Mirror 2007
- Vortex Generation and Pixel Calibration Using a Spatial Light Modulators for Maskless Lithography 2007
- Large-Stroke Self-Aligned Vertical Comb Drive Actuated Micromirror Arrays for Adaptive Optics Applications 2007
- Compact optical design for a dual-axes confocal endoscopic microscope 2007
- Three-Dimensional In Vivo Real Time Imaging By A Miniature Dual-Axes Confocal Microscope Based on a Two-Dimensional MEMS Scanner 2007
- High Reflectivity Broadband Photonic Crystal Mirror MEMS Scanner 2007
- MEMS Based Dual-axes Confocal Microscope for in-vivo Imaging 2007
- An External Cavity Tunable Laser with a Low-Loss Narrowband MEMS Tunable Blazed Grating 2007
- Displacement Sensing with a Mechanically Tunable Photonic Crystal 2007
- Optical Bandpass Filter with Tunable Chromatic Dispersion and Optical Bandwidth Using a Variable MEMS Reflector 2007
- Single-film Broadband Photonic Crystal Micro-mirror with Large Angular Range and Low Polarization Dependence 2007
- Pull-in Analysis of Scanners Actuated by Electrostatic Vertical Combdrives 2007
- Toward portable two-photon fluorescence micro-endoscopy using a two-dimensional microelectromechanical (MEMS) scanning mirror 2007
- Monolithic Photonic Crystals 2007
- Optical MEMS Based on High-Reflectivity Photonic Crystals 2007
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Algorithms for the synthesis of complex-value spectral filters with an array of micromechanical mirrors
OPTICS EXPRESS
2006; 14 (26): 12590-12612
Abstract
We study optical spectral filter synthesis with arrays of piston-actuated micro-mirrors. We propose two algorithms for the calculation of the positions of the micro-mirrors, giving us control of both the amplitude and phase of the synthetic filter. Both algorithms for filter synthesis are explored in an analytic version and in numerical searches for the least deviations between the target and the synthesized filter. We measure the quality of the filter both in terms of the deviations and in filter transmissivity, and present results of numerical simulations for a wide selection of target filters. We find that numerical searches can sometimes yield considerable improvement in the filter synthesis compared to the analytic approximation.
View details for Web of Science ID 000243144600005
View details for PubMedID 19532151
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Tunable optical bandpass filter with variable-aperture MEMS reflector
JOURNAL OF LIGHTWAVE TECHNOLOGY
2006; 24 (12): 5095-5102
View details for DOI 10.1109/JLT.2006.884987
View details for Web of Science ID 000243888600060
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Micromachined bubble-jet cell sorter with multiple operation modes
13th International Conference on Solid-State Sensors, Actuators and Microsystems
ELSEVIER SCIENCE SA. 2006: 523–29
View details for DOI 10.1016/j.snb.2006.05.011
View details for Web of Science ID 000239876900029
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Single fiber confocal microscope with a two-axis gimbaled MEMS scanner for cellular imaging
OPTICS EXPRESS
2006; 14 (19): 8604-8612
Abstract
We present a single fiber reflectance confocal microscope with a two dimensional MEMS gimbaled scanner. Achieved lateral and axial resolutions are 0.82 mum and 13 mum, respectively. The field of view is 140 x 100 mum at 8 frames/second. Images and videos of cell phantoms and tissue are presented with sub-cellular resolution.
View details for Web of Science ID 000240638700016
View details for PubMedID 19529240
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Micromachined Fourier transform spectrometer on silicon optical bench platform
13th International Conference on Solid-State Sensors, Actuators and Microsystems
ELSEVIER SCIENCE SA. 2006: 523–530
View details for DOI 10.1016/j.sna.2005.12.022
View details for Web of Science ID 000239295000072
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Fast-scanning two-photon fluorescence imaging based on a microelectromechanical systems two-dimensional scanning mirror
OPTICS LETTERS
2006; 31 (13): 2018-2020
Abstract
Towards overcoming the size limitations of conventional two-photon fluorescence microscopy, we introduce two-photon imaging based on microelectromechanical systems (MEMS) scanners. Single crystalline silicon scanning mirrors that are 0.75 mm x 0.75 mm in size and driven in two dimensions by microfabricated vertical comb electrostatic actuators can provide optical deflection angles through a range of approximately16 degrees . Using such scanners we demonstrated two-photon microscopy and microendoscopy with fast-axis acquisition rates up to 3.52 kHz.
View details for Web of Science ID 000238494600026
View details for PubMedID 16770418
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High fill-factor two-axis gimbaled tip-tilt-piston micromirror array actuated by self-aligned vertical electrostatic combdrives
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2006; 15 (3): 563-571
View details for DOI 10.1109/JMEMS.2006.876666
View details for Web of Science ID 000238311000014
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Tunable blazed gratings
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2006; 15 (3): 597-604
View details for DOI 10.1109/MEMS.2006.872241
View details for Web of Science ID 000238311000018
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Tunable wavelength demultiplexer and OCDMA code hopping using a 10-mu s-tuning MEMS-actuated Gires-Tournois filter
IEEE PHOTONICS TECHNOLOGY LETTERS
2006; 18 (9-12): 1398-1400
View details for DOI 10.1109/LPT.2006.876999
View details for Web of Science ID 000238708300133
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Microoptical characterization of piezoelectric vibratory microinjections in Drosophila embryos for genome-wide RNAi screen
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2006; 15 (2): 277-286
View details for DOI 10.1109/JMEMS.2006.872242
View details for Web of Science ID 000236770200001
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Air-bridged photonic crystal slabs at visible and near-infrared wavelengths
PHYSICAL REVIEW B
2006; 73 (11)
View details for DOI 10.1103/PhysRevB.73.115126
View details for Web of Science ID 000236467300064
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Automated MEMS-based Drosophila embryo injection system for high-throughput RNAi screens
LAB ON A CHIP
2006; 6 (8): 1012-1019
Abstract
We have developed an automated system based on microelectromechanical systems (MEMS) injectors for reliable mass-injection of Drosophila embryos. Targeted applications are high-throughput RNA interference (RNAi) screens. Our injection needles are made of silicon nitride. The liquid to be injected is stored in an integrated 500 nl reservoir, and an externally applied air pressure pulse precisely controls the injected volume. A steady-state water flow rate per applied pressure of 1.2 nl s(-1) bar(-1) was measured for a needle with channel width, height and length of 6.1 microm, 2.3 microm and 350 microm, respectively. A typical volume of 60 pl per embryo can be reliably and rapidly delivered within tens of milliseconds. Theoretical predictions of flow rates match measured values within +/-10%. Embryos are attached to a glass slide surface and covered with oil. Packages with the injector chip and the embryo slide are mounted on motorized xyz-stages. Two cameras allow the user to quickly align the needle tip to alignment marks on the glass slide. Our system then automatically screens the glass slide for embryos and reliably detects and injects more than 98% of all embryos. Survival rates after deionized (DI) water injection of 80% and higher were achieved. A first RNAi experiment was successfully performed with double-stranded RNA (dsRNA) corresponding to the segment polarity gene armadillo at a concentration of 0.01 microM. Almost 80% of the injected embryos expressed an expected strong loss-of-function phenotype. Our system can replace current manual injection technologies and will support systematic identification of Drosophila gene functions.
View details for DOI 10.1039/b600238b
View details for Web of Science ID 000239313800007
View details for PubMedID 16874371
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Two-dimensional MEMS scanner for dual-axes confocal in vivo microscopy
19th IEEE International Conference on Micro Electro Mechanical Systems (MEMS 2006)
IEEE. 2006: 862–865
View details for Web of Science ID 000236994500216
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Large-stroke self-aligned vertical comb drive actuators for adaptive optics applications
Conference on MEMS/MOEMS Components and Their Applications III
SPIE-INT SOC OPTICAL ENGINEERING. 2006
View details for DOI 10.1117/12.656508
View details for Web of Science ID 000237171400026
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High-sensitivity interferometric schemes for ML2 micromirror calibrations
Conference on Emerging Lithographic Technologies X
SPIE-INT SOC OPTICAL ENGINEERING. 2006
View details for DOI 10.1117/12.656553
View details for Web of Science ID 000238249800034
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Chip-scale high-speed Fourier-transform spectrometer based on a combination of a Michelson and a Fabry-Perot interferometer
5th IEEE Sensors Conference
IEEE. 2006: 412–415
View details for Web of Science ID 000248587500105
- High Capacity Optical Packet Switch Based on a Waveguide Grating Router Operated over Multiple FSRs 2006
- Superresolution Image Enhancement in Digital Photomicrography by Subpixel Translation using a Scanning Micromirror 2006
- Micromechanical Diffractive Optical Filters for Spectroscopy 2006
- Single-Crystal-Silicon Continuous Membrane Deformable Mirror Array for Adaptive Optics 2006
- Micromirror-based scan range enhancement in Fourier-domain optical coherence tomography 2006
- Spatial Light Modulators for Maskless Lithography 2006
- Dual quarter-wave retardation based polarization beam splitting in photonic crystal slabs 2006
- Dual-Axes Confocal Fluorescence Microscopy with a Two-Dimensional MEMS Scanner 2006
- Single Fiber Confocal Microscope Using a Two-Axis Microscanner for Cellular Imaging 2006
- Coupled Torsional Cantilevers for label-free single-molecule bio-detection and nanomaterials characterization 2006
- Higher-Harmonic Force Detection in Dynamic Force Microscopy Handbook of Nanotechnology Springer Verlag. 2006; 2: 717–736
- High-sensitivity interferometric schemes for ML2 micromirror calibrations 2006
- Optical MEMS for Light Wave Communication (Invited Paper) Journal of Lightwave Technology 2006; 24 (12): 4433-4454.
- Large-Stroke Self-Aligned Vertical Comb Drive Actuators for Adaptive Optics Applications 2006
- Compact Laser Scanning Distance Sensor with a Two-axis Gimbaled Microscanner for Volumetric Imaging 2006
- Fast-scanning Two-photon Fluorescence Imaging Using a Microelectromechanical Systems (MEMS) Two-dimensional Scanning Mirror 2006
- Photonic Crystals as Angle-Insensitive Broadband Mirrors 2006
- A reconfigurable optical demultiplexer based on a MEMS deformable blazed grating 2006
- MEMS Based Dual-axes Confocal Reflectance Handheld Microscope for in vivo Imaging 2006
- External Fiber Fabry-Perot Acoustic Sensor Based on Photonic Crystal Mirror 2006
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Reconfigurable near-infrared optical filter with a micromechanical diffractive Fresnel lens
IEEE PHOTONICS TECHNOLOGY LETTERS
2005; 17 (12): 2622-2624
View details for DOI 10.1109/LPT.2005.859186
View details for Web of Science ID 000233621000041
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Effects of through-focus symmetry in maskless lithography using micromirror arrays
49th International Conference on Electron, Ion, and Photon Beam Technology and Nanofabrication
A V S AMER INST PHYSICS. 2005: 2738–42
View details for DOI 10.1116/1.2062407
View details for Web of Science ID 000234613200088
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Microoptical characterization and modeling of positioning forces on drosophila embryos self-assembled in two-dimensional arrays
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2005; 14 (5): 1187-1197
View details for DOI 10.1109/JMEMS.2005.851834
View details for Web of Science ID 000232571000032
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Displacement sensing using evanescent tunneling between guided resonances in photonic crystal slabs
JOURNAL OF APPLIED PHYSICS
2005; 98 (3)
View details for DOI 10.1063/1.1999031
View details for Web of Science ID 000231246100002
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Micro-optical characterization of fluidic self-assembly of Drosophila embryos through surface tension: Principle, simulation and experiments
International Conference on Optical MEMS and Their Applications
OPTICAL SOC JAPAN. 2005: 352–57
View details for Web of Science ID 000232089300016
- Vertical Combdrives - Design and Implementation MEMS/NEMS Handbook Springer-Verlag New York Inc.. 2005: 393–420
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Near-field sensor using photonic crystal slabs
Conference on Lasers and Electro-Optics (CLEO)
OPTICAL SOC AMERICA. 2005: 837–839
View details for Web of Science ID 000234819901022
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High-resolution microelectromechanical scanners for miniaturized dual-axes confocal microscopes
Conference on MOEMS Display and Imaging Systems III
SPIE-INT SOC OPTICAL ENGINEERING. 2005: 132–135
View details for DOI 10.1117/12.597331
View details for Web of Science ID 000228764100017
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Micromachined Fourier transform spectrometer on silicon optical bench platform
13th International Conference on Solid-State Sensors, Actuators and Microsystems
IEEE. 2005: 1250–1254
View details for Web of Science ID 000232189100308
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Silicon masking layers for fabrication of high aspect ratio MEMS
10th IEEE/LEOS International Conference on Optical MEMs and Their Applications
IEEE. 2005: 85–86
View details for Web of Science ID 000232362400041
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Summary of adaptive optics at Stanford
4th International Workshop on Adaptive Optics for Industry and Medicine
SPRINGER-VERLAG BERLIN. 2005: 53–59
View details for Web of Science ID 000232738200007
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Design and operation of a micromachined bubble-jet cell sorter
13th International Conference on Solid-State Sensors, Actuators and Microsystems
IEEE. 2005: 441–444
View details for Web of Science ID 000232189100106
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Excitation of non-degenerate resonances through breaking of mirror symmetry in photonic crystal slabs
Conference on Lasers and Electro-Optics (CLEO)
OPTICAL SOC AMERICA. 2005: 828–830
View details for Web of Science ID 000234819901019
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Micromachined silicon diffractive optical force encoders: Principles and applications in biology
8th International Conference on Miniaturized Systems for Chemistry and Life Sciences
ROYAL SOC CHEMISTRY. 2005: 518–20
View details for Web of Science ID 000229017400172
- Near-Field Sensor Using Photonic Crystal Slabs 2005
- Excitation of Non-Degenerate Resonances through Breaking of Mirror Symmetry in Photonic Crystal Slabs 2005
- Design and Operation of a Micromachined Bubble-Jet Cell Sorter 2005
- Silicon Masking Layers for Fabrication of High Aspect Ratio MEMS 2005
- A Micro-Mechanical Fresnel Lens for Spectral Filtering 2005
- Reconfigurable Near-Infrared Optical Filter with Micromechanical Diffractive Fresnel Lens IEEE Photonics Technology Letters 2005; 17 (12): 2622-2624
- A wavelength selective switch with flat passband using a free-space grating and MEMS phase-shifters 2005
- Micromachined Fourier Transform Spectrometer on Silicon Optical Bench Platform 2005
- High-resolution microelectromechanical scanners for miniaturized dual-axes confocal microscopes 2005
- Understanding Through-Focus Symmetry in Maskless Lithography Using Micromirror Arrays 2005
- Scalable optical switch fabric for avionic networks 2005
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Photonic crystal slabs demonstrating strong broadband suppression of transmission in the presence of disorders
OPTICS LETTERS
2004; 29 (23): 2782-2784
Abstract
We characterize the transmission spectra of out-of-plane, normal-incidence light of two-dimensional silicon photonic crystal slabs and observe excellent agreement between the measured data and finite-difference time-domain simulations over the 1050-1600-nm wavelength range. Crystals that are 340 nm thick and have holes of 330-nm radius on a square lattice of 998-nm pitch show 20-dB extinction in transmission from 1220 to 1255 nm. Increasing the hole radius to 450 nm broadens the extinction band further, and we obtain >85% extinction from 1310 to 1550 nm. Discrepancies between simulation and measurement are ascribed to disorder in the photonic lattice, which is measured through image processing on high-resolution scanning electron micrographs. Analysis of crystal imperfections indicates that they tend to average out narrowband spectral features, while having relatively small effects on broadband features.
View details for PubMedID 15605504
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Analysis of resonant frequency of fast scanning micromirror with vertical combdrives
IEICE TRANSACTIONS ON ELECTRONICS
2004; E87C (11): 2006-2008
View details for Web of Science ID 000225210400040
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Fabrication method for elastomer spatial light modulators for short wavelength maskless lithography
12th International Conference on Solid-State Sensors, Actuators and Microsystems (TRANSDUCERS 03)
ELSEVIER SCIENCE SA. 2004: 528–35
View details for DOI 10.1016/j.sna.2003.12.001
View details for Web of Science ID 000223704800057
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Design and operation of a microfluidic sorter for Drosophila embryos
12th International Conference on Solid-State Sensors, Actuators and Microsystems (TRANSDUCERS 03)
ELSEVIER SCIENCE SA. 2004: 59–66
View details for DOI 10.1016/j.snu.2003.10.015
View details for Web of Science ID 000223969400009
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Micromachined silicon force sensor based on diffractive optical encoders for characterization of microinjection
12th International Conference on Solid-State Sensors, Actuators and Microsystems (TRANSDUCERS 03)
ELSEVIER SCIENCE SA. 2004: 197–203
View details for DOI 10.1016/j.sna.2003.11.028
View details for Web of Science ID 000223704800011
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High-resolution imaging of elastic properties using harmonic cantilevers
12th International Conference on Solid-State Sensors, Actuators and Microsystems (TRANSDUCERS 03)
ELSEVIER SCIENCE SA. 2004: 183–90
View details for DOI 10.1016/j.sna.2003.11.031
View details for Web of Science ID 000223704800009
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Characterization of fluidic microassembly for immobilization and positioning of Drosophila embryos in 2-D arrays
12th International Conference on Solid-State Sensors, Actuators and Microsystems (TRANSDUCERS 03)
ELSEVIER SCIENCE SA. 2004: 191–96
View details for DOI 10.1016/j.sna.2003.11.021
View details for Web of Science ID 000223704800010
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Single-crystalline silicon micromirrors actuated by self-aligned vertical electrostatic combdrives with piston-motion and rotation capability
12th International Conference on Solid-State Sensors, Actuators and Microsystems (TRANSDUCERS 03)
ELSEVIER SCIENCE SA. 2004: 423–28
View details for DOI 10.1016/j.sna.2003.11.024
View details for Web of Science ID 000223704800041
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Lithography process for trench pattern above large cavity to fabricate fast scanning micromirror
IEICE TRANSACTIONS ON ELECTRONICS
2004; E87C (8): 1395-1398
View details for Web of Science ID 000223264700030
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Tunable optical transversal filters based on a Gires-Tournois interferometer with MEMS phase shifters
IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS
2004; 10 (3): 588-597
View details for DOI 10.1109/JSTQE.2004.828477
View details for Web of Science ID 000223299300022
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Introduction to the issue on optical microsystems
IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS
2004; 10 (3): 433-434
View details for Web of Science ID 000223299300001
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Micromechanical gratings for visible and near-infrared spectroscopy
IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS
2004; 10 (3): 604-613
View details for DOI 10.1109/JSTQE.2004.82849
View details for Web of Science ID 000223299300024
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Angular and polarization properties of a photonic crystal slab mirror
LEOS Topical Meeting on Photonic Crystals and Holey Fibers
OPTICAL SOC AMER. 2004: 1575–82
Abstract
It was recently demonstrated that a photonic crystal slab can function as a mirror for externally incident light along a normal direction with near-complete reflectivity over a broad wavelength range. We analyze the angular and polarization properties of such photonic crystal slab mirror, and show such reflectivity occurs over a sizable angular range for both polarizations. We also show that such mirror can be designed to reflect one polarization completely, while allowing 100% transmission for the other polarization, thus behaving as a polarization splitter with a complete contrast. The theoretical analysis is validated by comparing with experimental measurements.
View details for Web of Science ID 000220908100012
View details for PubMedID 19474983
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Resonant harmonic response in tapping-mode atomic force microscopy
PHYSICAL REVIEW B
2004; 69 (16)
View details for DOI 10.1103/PhysRevB.69.165416
View details for Web of Science ID 000221427100093
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Snap down voltage of a fast-scanning micromirror with vertical electrostatic combdrives
JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS & EXPRESS LETTERS
2004; 43 (2B): L284-L286
View details for Web of Science ID 000220378600016
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Bonding of two silicon layers above a gap to fabricate a fast scanning micromirror
JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS & EXPRESS LETTERS
2004; 43 (1A-B): L50-L52
View details for DOI 10.1143/JJAP.43.L50
View details for Web of Science ID 000220092700016
- Automated MEMS Based Fruit Fly Embryo Injection System for Genome-Wide High-Throughput RNAi Screens 2004
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Mechanically switchable photonic crystal structures based on coupled photonic crystal slabs
Conference on Photonic Crystal Materials and Devices II
SPIE-INT SOC OPTICAL ENGINEERING. 2004: 299–306
View details for DOI 10.1117/12.521541
View details for Web of Science ID 000223224600033
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Variable bandwidth optical filters with vertical micromirrors and silicon optical bench alignment technology
17th Annual Meeting of the IEEE-Lasers-and-Electro-Optics-Society
IEEE. 2004: 531–532
View details for Web of Science ID 000225390900264
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Tunable optical wavelength deinterleaver based on tunable MEMS blazed gratings
17th Annual Meeting of the IEEE-Lasers-and-Electro-Optics-Society
IEEE. 2004: 320–321
View details for Web of Science ID 000225390900159
- Micro-Optical Characterization and Modeling of Microfluidic Self-Assembly in Biology 2004
- Interference-Based Optical MEMS Filters 2004
- Tunable external cavity laser with a stationary deformable MEMS grating. 2004
- Ultrasonic Microinjection Characterized by Integrated Micro-optical Force Encoder 2004
- Variable Bandwidth Optical Filters with Vertical Micromirrors and Silicon Optical Bench Alignment Technology 2004
- A 10-ms-tuning MEMS-Actuated Gires-Tournois Filter for use as a Tunable Wavelength Demultiplexer and a TunableOCDMA Encoder/Decoder 2004
- Micromachined Silicon Diffractive Optical Force Encoders: Principles and Applications in Biology 2004
- Vertical micromirror fabricated in (110) silicon device layer by combination of KOH and DRIE etch 2004
- A Transmissive Interferometric Light Modulator based on Silicon Nitride Double-Half-Wave Filter Structure 2004
- Two-Axis Gimbaled Microscanner in Double SOI Layers Actuated by Self-Aligned Vertical Electrostatic Combdrive 2004
- Surface Micromachined Elastomer Spatial Light modulators for Extreme Ultra violet Radiation 2004
- High Fill-Factor Two-Axis Gimbaled Tip-Tilt-Piston Micromirror Array Actuated by Self-Aligned Vertical Electrostatic Combdrives 2004
- Tunable Optical Wavelength Deinterleaver based on Tunable MEMS Blazed Gratings 2004
- Mechanically switchable photonic crystal structures based on coupled photonic crystal slabs 2004
- Two-Dimensional Photonic Crystals at Visible Wavelengths 2004
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The torque of high speed scanning micromirrors with vertical combdrives
JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS & EXPRESS LETTERS
2003; 42 (12A): L1449-L1451
View details for DOI 10.1143/JJAP.42.L1449
View details for Web of Science ID 000187509800015
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Scaling Internet routers using optics
SIGCOMM 2003 Conference
ASSOC COMPUTING MACHINERY. 2003: 189–200
View details for Web of Science ID 000188215800017
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Self-aligned vertical electrostatic combdrives for micromirror actuation
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
2003; 12 (4): 458-464
View details for DOI 10.1109/JMEMS.2003.811728
View details for Web of Science ID 000184649700007
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Optical wavelength filtering by diffraction from a surface relief (vol 28, pg 447, 2003)
OPTICS LETTERS
2003; 28 (12): 1055-1055
View details for Web of Science ID 000183362700031
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Displacement-sensitive photonic crystal structures based on guided resonance in photonic crystal slabs
APPLIED PHYSICS LETTERS
2003; 82 (13): 1999-2001
View details for DOI 10.1063/1.1563739
View details for Web of Science ID 000181801100001
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Optical wavelength filtering by diffraction from a surface relief
OPTICS LETTERS
2003; 28 (6): 447-449
Abstract
We present an analytical solution to the problem of finding a diffractive surface relief that generates a specific optical amplitude and phase spectral reflection in a particular direction. We show that any discrete finite impulse response filter can be generated to within a multiplicative constant at nonzero frequencies. We propose an implementation of such a filter that works in the visible and the near infrared, based on a two-dimensional array of dual-state tiltable mirrors. A 1024 x 1024 array results in a 1024-tap filter with 10-bit quantization of the impulse response. The applications of such a device include spectroscopy and wavelength-division multiplex switching.
View details for Web of Science ID 000181411300023
View details for PubMedID 12659275
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Configurable spectral filter with an array of diffraction gratings
IEEE/LEOS International Conference on Optical MEMS
IEEE. 2003: 30–31
View details for Web of Science ID 000185581900015
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MOEMS spatial light modulator development at the Center for Adaptive Optics
Conference on MOEMS and Miniaturized Systems III
SPIE-INT SOC OPTICAL ENGINEERING. 2003: 172–179
View details for Web of Science ID 000181865000028
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High-resolution, high-speed microscanner in single-crystalline silicon actuated by self-aligned dual-mode vertical electrostatic combdrive with capability for phased array operation
12th International Conference on Solid-State Sensors, Actuators and Microsystems (TRANSDUCERS 03)
IEEE. 2003: 576–579
View details for Web of Science ID 000184567300145
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Elastomer spatial light modulators for extreme ultraviolet lithography
12th International Conference on Solid-State Sensors, Actuators and Microsystems (TRANSDUCERS 03)
IEEE. 2003: 1458–1461
View details for Web of Science ID 000184567300366
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Femtosecond direct space-to-time pulse shaping with MEMS micromirror arrays
IEEE/LEOS International Conference on Optical MEMS
IEEE. 2003: 24–25
View details for Web of Science ID 000185581900012
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MOEMS spatial light modulator development at the Center for Adaptive Optics
Conference on MOEMS Display and Imaging Systems
SPIE-INT SOC OPTICAL ENGINEERING. 2003: 172–179
View details for Web of Science ID 000181866900018
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Tunable wavelength multiplexer/demultiplexer using a MEMS Gires-Tournois interferometer
16th Annual Meeting of the IEEE Lasers and Electro-Optics Society
IEEE. 2003: 521–522
View details for Web of Science ID 000188359700263
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Harmonic cantilevers for nanomechanical sensing of elastic properties
12th International Conference on Solid-State Sensors, Actuators and Microsystems (TRANSDUCERS 03)
IEEE. 2003: 1124–1127
View details for Web of Science ID 000184567300282
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Tunable bandwidth optical filter based on MEMS Gires-Tournois interferometer
IEEE/LEOS International Conference on Optical MEMS
IEEE. 2003: 32–33
View details for Web of Science ID 000185581900016
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Microfluidic switch for embryo and cell sorting
12th International Conference on Solid-State Sensors, Actuators and Microsystems (TRANSDUCERS 03)
IEEE. 2003: 659–662
View details for Web of Science ID 000184567300166
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Integrated optical diffractive micrograting-based injection force sensor
12th International Conference on Solid-State Sensors, Actuators and Microsystems (TRANSDUCERS 03)
IEEE. 2003: 1051–1054
View details for Web of Science ID 000184567300264
- Programmable Optical Wavelength Filter Based on Diffraction from a 2‑D MEMS Micromirror Array 2003
- Integrated Optical Diffractive Micrograting-Based Injection Force Sensor 2003
- High-Precision Characterization of Embryo Positioning Force Using MEMS Optical Encoder 2003
- Tunable Wavelength Multiplexer/Demultiplexer using a MEMS Gires-Tournois Interferometer 2003
- Harmonic Cantilevers for Nanomechanical Sensing of Elastic Properties 2003
- Elastomer Spatial Light Modulators for Extreme Ultraviolet Lithography 2003
- Microoptical phased arrays for spatial and spectral switching 2003
- Optical Microphone Based on a Modulated Diffractive Lens IEEE Photonics Technology Letters 2003; 15 (10): 1431-1433
- Characterization of Drosophila Embryos Immobilized by Fluidic Microassembly 2003
- Tunable bandwidth optical filter based on MEMS Gires‑Tournois Interferometer 2003
- Optical MEMS - Fabrication, Scaling and Design of Microoptical Devices and Systems 2003
- MOEMS Spatial Light Modulator Development at the Center for Adaptive Optics 2003
- Microfluidic Switch for Embryo and Cell Sorting 2003
- Configurable spectral filter with an array of diffraction gratings 2003
- Femtosecond Direct Space-to-Time Pulse Shaping with MEMS Micromirror Arrays 2003
- High-Resolution, High-Speed Microscanner in Single-Crystalline Silicon Actuated by Self-Aligned Dual-Mode Vertical Electrostatic Combdrive with Capability for Phased Array Operation 2003
- MEMS optical wavelength deinterleaver with continuously variable channel spacing and center wavelength IEEE Photonics Technology Letters 2003; 15 (3): 425-427
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Optical characterization of high speed scanning micromirrors with vertical combdrives
JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS & EXPRESS LETTERS
2002; 41 (10B): L1169-L1171
View details for DOI 10.1143/JJAP.41.L1169
View details for Web of Science ID 000179893900014
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Process for high speed micro electromechanical systems (MEMS) scanning mirrors with vertical comb drives
JAPANESE JOURNAL OF APPLIED PHYSICS PART 2-LETTERS & EXPRESS LETTERS
2002; 41 (8A): L899-L901
View details for DOI 10.1143/JJAP.41.L899
View details for Web of Science ID 000177527400012
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Dual-mode micromirrors for optical phased array applications
Transducers 2001 Conference/Eurosensor XVth Conference
ELSEVIER SCIENCE SA. 2002: 21–26
View details for Web of Science ID 000176297000004
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Coherent micromirror arrays
OPTICS LETTERS
2002; 27 (5): 366-368
Abstract
A one-dimensional, spatial light phase modulator consists of a coherent array of programmable micromirrors. Each micromirror has rotation as well as elevation control to permit high-fidelity, piecewise linear approximations to a desired spatial phase profile. We demonstrate programmable, coherent spatial modulation by configuring a four-micromirror array to act as a blazed diffraction grating, showing five diffraction orders. In sharp contrast, adjustment of each mirror elevation converts the grating into the equivalent of a single, large tilted mirror that reflects only in a new specular direction. Higher-order diffraction is effectively suppressed.
View details for Web of Science ID 000174143400028
View details for PubMedID 18007805
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Introduction to the issue on optical MEMS
IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS
2002; 8 (1): 1-3
View details for Web of Science ID 000174519300001
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Microoptical phased arrays for spatial and spectral switching
Conference on Design, Test, Integration, and Packaging of MEMS/MOEMS 2002
SPIE-INT SOC OPTICAL ENGINEERING. 2002: 1–9
View details for Web of Science ID 000176995300001
- High Speed MEMS Scanning Mirror with Vertical Comb Drive 2002
- Microoptical phased arrays for spatial and spectral switching 2002
- Positioning and Immobilization of Drosophila Embryos in 2‑D Arrays for Drug Injection 2002
- Segmented Deformable Micromirror for Free-Space Optical Communication 2002
- Dual mode micromirrors for optical phased array applications Sensors and Actuators: A. Physical 2002; A97-98: 21-26
- Micromachined Hollow Needle with Integrated Pressure Sensor for Precise, Calibrated Injection into Cells and Embryos 2002
- Dynamic Diffractive Optical Elements based on MEMS Technology 2002
- Micromirror Array Phase Modulator for Ultrashort Optical Pulse Shaping 2002
- Optical Communication with Coherent MEMS Arrays 2002
- Tunable Chromatic Dispersion Compensators Using MEMS Gires-Tournois Interferometers 2002
- MEMS Switchable WDM De interleaver Based on a Gires-Tournois Interferometer 2001
- Effects of Mirror Surface Deformation in Optical Delay Lines Based on Resonant-Scanning Micromirrors 2001
- Phased Arrays of Micromirrors for Programmable Shaping of Ultrashort Pulses 2001
- Self-Aligned Vertical Combdrive Actuators for Optical Scanning Micromirrors 2001
- Dual Mode Micromirrors for Optical Phased Arrays Applications 2001
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Narrow-band light emission in semiconductor-fibre asymmetric waveguide coupler
ELECTRONICS LETTERS
2000; 36 (16): 1378-1379
View details for Web of Science ID 000088762800031
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Scalable optical cross-connect switch using micromachined mirrors
IEEE PHOTONICS TECHNOLOGY LETTERS
2000; 12 (7): 882-884
View details for Web of Science ID 000088505800042
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Free space communication link using a grating light modulator
10th International Conference on Solid-State Sensors and Actuators
ELSEVIER SCIENCE SA. 2000: 6–10
View details for Web of Science ID 000087144800002
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Wavelength-selective semiconductor in-line fibre photodetectors
ELECTRONICS LETTERS
2000; 36 (6): 515-516
View details for Web of Science ID 000086381000023
- Low Power Wireless Readout of Autonomous Sensor Wafer using MEMS Grating Light Modulator 2000
- Micro-electro- mechanical systems spatial light modulator development 2000
- Surface-micromachined mirrors for scalable fiber optic switching applications 2000
- A raster-scanning full-motion video display using polysilicon micromachined mirrors Sensors & Actuators A 2000; 83 (1-3): 291-296
- Compact Optical Delay Line Based on Scanning Surface Micromachined Polysilicon Micromirrors 2000
- Miniature variable optical delay using silicon micromachined scanning mirrors 2000
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GaAs AlGaAs multiple-quantum-well in-line fiber intensity modulator
APPLIED PHYSICS LETTERS
1999; 75 (3): 310-312
View details for Web of Science ID 000081409000002
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Optical raster-scanning displays based on surface-micromachined polysilicon mirrors
IEEE JOURNAL OF SELECTED TOPICS IN QUANTUM ELECTRONICS
1999; 5 (1): 67-74
View details for Web of Science ID 000079972900012
- A Raster-Scanning Full-Motion Video Display Using Polysilicon Micromachined Mirrors 1999
- Micromachined Scalable Fiber-Optic Switch 1999
- Scalable Fiber Optic Switch Using Micromachined Mirrors 1999
- Robustness and Reliability of Micromachined Scanning Mirrors 1999
- Static and Dynamic Characterization of Polysilicon Surface-Micromachined Actuators 1999
- A GaAs/AlGaAs narrow bandwidth in-line fiber filter 1999
- Free-Space Communication Link Using a Grating Light Modulator 1999
- Integrated Micromachined Scanning Display Systems 1999
- Micromachined grating light modulators for wireless sensor networks 1999
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Polysilicon optical microscanners for laser scanning displays
9th International Conference on Solid-State Sensors and Actuators
ELSEVIER SCIENCE SA. 1998: 195–99
View details for Web of Science ID 000075835900030
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Electrostatic combdrive-actuated micromirrors for laser-beam scanning and positioning
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
1998; 7 (1): 27-37
View details for Web of Science ID 000073005900004
- Electrostatic Combdrive-Actuated Micromirrors for Laser-Beam Scanning and Positioning IEEE Journal of MicroElectroMechanical Systems (JMEMS) 1998; 7 (1): 27-37
- In-line fiber-optic filter using GaAs ARROW waveguide 1998
- Micromachined Mirrors in a Raster Scanning Display System 1998
- Polysilicon optical microscanners for laser scanning displays 1998
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Compact 2D laser beam scanner with fan laser array and Si micromachined microscanner
ELECTRONICS LETTERS
1997; 33 (13): 1143-1145
View details for Web of Science ID 000072040900030
- Micromachined microscanners for optical scanning 1997
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Actuated polysilicon micromirrors for raster-scanning displays
9th International Conference on Solid-State Sensors and Actuators
IEEE. 1997: 323–326
View details for Web of Science ID A1997BJ35B00079
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Micromachined microscanners for optical scanning
Conference on Miniaturized Systems with Micro-Optics and Micromechanics II
SPIE - INT SOC OPTICAL ENGINEERING. 1997: 82–90
View details for Web of Science ID A1997BH70G00009
- High-Resolution Silicon Surface Micromachined Displays 1997
- Actuated Polysilicon Micromirrors for Raster-Scanning Displays 1997
- Compact 2D laser beam scanner with fan laser array and Si micromachined microscanner Electronics Letters (UK), IEE 1997; 33 (13): 1143-5
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Micromachined polysilicon microscanners for barcode readers
IEEE PHOTONICS TECHNOLOGY LETTERS
1996; 8 (12): 1707-1709
View details for Web of Science ID A1996VV26000042
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Linear microvibromotor for positioning optical components
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
1996; 5 (3): 159-165
View details for Web of Science ID A1996VH43900003
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Surface-micromachined mirrors for laser-beam positioning
SENSORS AND ACTUATORS A-PHYSICAL
1996; 52 (1-3): 76-80
View details for Web of Science ID A1996UR00700012
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Laser-to-fiber coupling module using a micromachined alignment mirror
IEEE PHOTONICS TECHNOLOGY LETTERS
1996; 8 (3): 396-398
View details for Web of Science ID A1996TY86800031
- Silicon-micromachined micromirrors with integrated high-precision actuators for external-cavity semiconductor lasers IEEEPhotonics Techn. Letters 1996; 8 (1): 95-97
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Actuation of polysilicon surface-micromachined mirrors
Conference on Miniaturized Systems with Micro-Optics and Micromechanics
SPIE - INT SOC OPTICAL ENGINEERING. 1996: 53–59
View details for Web of Science ID A1996BF18M00007
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Surface-micromachined electrostatic-comb driven scanning micromirrors for barcode scanners
IEEE 9th Annual International Workshop on Micro Electro Mechanical Systems - An Investigation of Micro Structures, Sensors, Actuators, Machines and Systems
I E E E. 1996: 192–197
View details for Web of Science ID A1996BF27K00033
- Surface-micromachined electrostatic-comb driven scanning micromirrors for barcode scanners 1996
- Design and Fabrication of High-Performance Silicon Micromachined Resonant Microscanners for Optical Scanning Applications 1996
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Silicon-micromachined micromirrors with integrated high-precision actuators for external-cavity semiconductor lasers
IEEE PHOTONICS TECHNOLOGY LETTERS
1996; 8 (1): 95-97
View details for Web of Science ID A1996TN50000033
- Linear Microvibromotor for Positioning Optical Components IEEE Journal of MicroElectroMechanical Systems (JMEMS) 1996; 5 (3): 159-165
- Actuated Micromachined Microreflector with Two Degrees of Freedom for Integrated Optical Systems 1996
- Surface-Micromachined Mirrors for Laser-Beam Positioning Sensors and Actuators A (Physical) 1996; A52 (13): 76-80
- High-Precision Silicon Micromachined Micromirrors for Laser Beam Scanning and Positioning 1996
- Actuation of polysilicon surface-micromachined mirrors 1996
- Linear Vibromotor-Actuated Micromachined microreflector for Integrated Optical Systems 1996
- Laser-to-fiber Coupling Module Using a Micromachined Alignment Mirror IEEE Photonics Technology Letters 1996; 8 (3): 396-398
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OPTICAL-TRANSMISSION OF NARROW-BAND MILLIMETER-WAVE SIGNALS
IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES
1995; 43 (9): 2229-2240
View details for Web of Science ID A1995RU47900008
- High-precision Si-micromachined micromirrors with on-chip actuation for external cavity semiconductor lasers 1995
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Linear microvibromotor for positioning optical components
8th IEEE International Workshop on Micro Electro Mechanical Systems (MEMS)
IEEE. 1995: 55–60
View details for Web of Science ID A1995BD67E00010
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Precision and performance of polysilicon micromirrors for hybrid integrated optics
Conference on Miniaturized Systems with Micro-Optics and Micromechanics/Laser Diode Optics II/Optical Engineering for Data Storage and Laser Imaging
SPIE - INT SOC OPTICAL ENGINEERING. 1995: 99–109
View details for Web of Science ID A1995BD11H00009
- Surface-micromachined active optical bench for optoelectronic integration and packaging 1995
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OPTOELECTRONIC PACKAGING USING SILICON SURFACE-MICROMACHINED ALIGNMENT MIRRORS
IEEE PHOTONICS TECHNOLOGY LETTERS
1995; 7 (1): 41-43
View details for Web of Science ID A1995QD67300014
- Optical Transmission of Narrowband Millimeter-Wave Signals IEEE Transactions on Microwave Theory and Techniques 1995; 43 (9): 2229-2240
- Precision and performance of polysilicon micromirrors for hybrid integrated optics 1995
- Polysilicon-micromachined optical devices 1995
- Optoelectronic packaging using silicon surface-micromachined alignment mirrors IEEEPhotonics Techn. Letters 1995; 7 (1): 41-43
- Surface-micromachined mirrors for laser-beam positioning 1995
- Integrated Laser to Fiber Coupling Module Using a Micromachined Alignment Mirror 1995
- Linear Microvibromotor for Positioning Optical Elements 1995
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TRANSMISSION OF 300 MBIT/S BPSK AT 39 GHZ USING FEEDFORWARD OPTICAL MODULATION
ELECTRONICS LETTERS
1994; 30 (2): 160-161
View details for Web of Science ID A1994MW04000044
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STABLE PICOSECOND PULSE GENERATION AT 46GHZ BY MODELOCKING OF A SEMICONDUCTOR-LASER OPERATING IN AN OPTOELECTRONIC PHASELOCKED LOOP
ELECTRONICS LETTERS
1994; 30 (1): 69-71
View details for Web of Science ID A1994MT57700049
- Stable Picosecond Pulse Generation at 46 GHz by Mode-Locking of a Semiconductor Laser Operating in an Optoelectronic Phase-Locked Loop Electronics Letters 1994; 30 (1): 69-71
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IMPACT-ACTUATED LINEAR MICROVIBROMOTOR FOR MICRO-OPTICAL SYSTEMS ON SILICON
1994 IEEE International Electron Devices Meeting
IEEE. 1994: 924–926
View details for Web of Science ID A1994BC55U00211
- High Data Rate Millimeter Wave Subcarrier Transmission Using Feedforward Optical Modulation 1994
- Impact-actuated linear microvibromotor for micro- optical systems on silicon 1994
- Transmission of 300 Mb/s BPSK at 39 GHz Using Feedforward Optical Modulation Electronics Letters 1994; 30 (2): 160-161
- Stable Picosecond Pulse Generation at 46 GHz by Passive Mode-Locking of a Semiconductor Laser Operating in an Optoelectronic Phase-Locked Loop 1994
- Micromachined alignment mirrors for opto-electronic packaging 1994
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OPTICAL FEEDBACK STABILIZATION OF THE INTENSITY OSCILLATIONS IN ULTRAHIGH-FREQUENCY PASSIVELY MODELOCKED MONOLITHIC QUANTUM-WELL LASERS
IEEE PHOTONICS TECHNOLOGY LETTERS
1993; 5 (11): 1264-1267
View details for Web of Science ID A1993MN04200002
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PULSE BUILDUP IN PASSIVELY MODE-LOCKED MONOLITHIC QUANTUM-WELL SEMICONDUCTOR-LASERS
APPLIED PHYSICS LETTERS
1993; 63 (15): 2021-2023
View details for Web of Science ID A1993MA97700003
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MILLIMETER-WAVE, MULTIGIGAHERTZ OPTICAL MODULATION BY FEEDFORWARD PHASE NOISE COMPENSATION OF A BEAT NOTE GENERATED BY PHOTOMIXING OF 2 LASER-DIODES
IEEE PHOTONICS TECHNOLOGY LETTERS
1993; 5 (5): 574-577
View details for Web of Science ID A1993LE08100031
- Optical Feedback Stabilization of the Intensity Oscillations in Ultra-high Frequency, Passively Modelocked, Monolithic, Quantum Well Lasers Photonics Techn. Lett. 1993; 5 (11): 1264-1267
- Millimeter wave optical transmission using a tunable laser beatnote source with feedforward compensation 1993
- Dynamics of pulse build-up in QW lasers passively mode-locked at millimeter wave frequencies 1993
- Pulse buildup in passively mode-locked quantum-well semiconductor lasers Applied Physics Letters 1993; 15 (63): 2021-2023
- Millimeter-Wave Frequency, Multi-Gigahertz Optical Modulation by Feedforward Phase Noise Compensation of a Beat Note Generated by Photomixing of Two Laser Diodes IEEEPhotonics Techn. Letters 1993; 5 (5): 574-577
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HIGH-FREQUENCY ATTENUATED TOTAL INTERNAL-REFLECTION LIGHT-MODULATOR
APPLIED PHYSICS LETTERS
1992; 61 (21): 2500-2502
View details for Web of Science ID A1992JZ02500002
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DEFORMABLE GRATING OPTICAL MODULATOR
OPTICS LETTERS
1992; 17 (9): 688-690
Abstract
A new type of light modulator, the deformable grating modulator, based on electrically controlling the amplitude of a micromachined phase grating is described. Mechanical motion of one quarter of a wavelength is sufficient for switching in this device. The small mechanical motion allows the use of structures with high mechanical resonance frequencies. We have developed a deformable grating modulator with a bandwidth of 1.8 MHz and a switching voltage of 3.2 V and have demonstrated modulation with 16 dB of contrast. Smaller devices with bandwidths of as much as 6.1 MHz and predicted switching voltages of less than 10 V were also fabricated.
View details for Web of Science ID A1992HP32800020
View details for PubMedID 19794599
- A deformable grating optical modulator Optics Letters 1992; 17 (9): 688-690
- An Attenuated Internal Reflection Modulator Applied Physics Letters 1992; 21 (61): 2500-2502
- Deformable grating optical modulator 1992
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ALL-SILICON INTEGRATED OPTICAL MODULATOR
IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS
1991; 9 (5): 704-710
View details for Web of Science ID A1991FW03000011
- High Speed Attenuated Internal reflection Modulators 1991
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PIGTAILED SINGLE-MODE FIBER OPTIC LIGHT-MODULATOR IN SILICON
IEEE PHOTONICS TECHNOLOGY LETTERS
1990; 2 (9): 640-642
View details for Web of Science ID A1990EB35300012
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A POLARIZATION-INDEPENDENT SILICON LIGHT-INTENSITY MODULATOR FOR 1.32-MU-M FIBER OPTICS
IEEE PHOTONICS TECHNOLOGY LETTERS
1990; 2 (4): 262-264
View details for Web of Science ID A1990CX91400013
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A SMALL-AREA LIGHT-INTENSITY MODULATOR IMPLEMENTED IN SILICON
IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC. 1989: 2614–14
View details for Web of Science ID A1989AW89000071
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ALL-SILICON INTEGRATED OPTICAL MODULATOR FOR 1.3-MU-M FIBER-OPTIC INTERCONNECTS
APPLIED PHYSICS LETTERS
1989; 55 (4): 349-350
View details for Web of Science ID A1989AG24200009
- Bulk piezoresistors for stable pressure sensors 1986