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1
Kallweit, David. "Controlled tilting micromirrors micromirrors with integrated optical feedback for high accuracy tilt sensing." Tönning Lübeck Marburg Der Andere Verl, 2007. http://d-nb.info/988248638/04.
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Jia, Kemiao. "The development and applications of high fill-factor, small footprint MEMS micromirrors and micromirror arrays." [Gainesville, Fla.] : University of Florida, 2009. http://purl.fcla.edu/fcla/etd/UFE0024997.
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Li, Li. "MEMS micromirrors for imaging applications." Thesis, University of Strathclyde, 2013. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=19508.
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Optical MEMS (microelectromechanical systems) are widely used in various applications. In this thesis, the design, simulation and characterisation of two optical MEMS devices for imaging applications, a varifocal micromirror and a 2D scanning micromirror, are introduced. Both devices have been fabricated using the commercial Silicon-on-Insulator multi-users MEMS processes (SOIMUMPs), in the 10 m thick Silicon-on-Insulator (SOI) wafer. Optical MEMS device with variable focal length is a critical component for imaging system miniaturisation. In this thesis, a thermally-actuated varifocal micromirror (VFM) with 1-mm-diameter aperture is introduced. The electrothermal actuation through Joule heating of the micromirror suspensions and the optothermal actuation using incident laser power absorption have been demonstrated as well as finite element method (FEM) simulation comparisons. Especially, the optical aberrations produced by this VFM have been statistically quantified to be negligible throughout the actuation range. A compact imaging system incorporating this VFM has been demonstrated with high quality imaging results. MEMS 2D scanners, or scanning micromirrors, are another type of optical MEMS which have been widely investigated for applications such as biomedical microscope imaging, projection, retinal display and optical switches for telecommunication network, etc. For large and fast scanning motions, the actuation scheme to scan a micromirror in two axes, the structural connections and arrangement are fundamental. The microscanner introduced utilises two types of actuators, electrothermal actuators and electrostatic comb-drives, to scan a 1.2-mm-diameter gold coated silicon micromirror in two orthogonal axes. With assistance of FEM software, CoventorWare, the structure optimisation of actuators and flexure connections are presented. The maximum optical scan angles in two axes by each type of actuator individually and by actuating the two at the same time have been characterised experimentally. By programming actuation signals, the microscanner has achieved a rectangular scan pattern with 7°x10° angular-scan-field at a line-scan rate of around 1656 Hz.
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Bauer, Ralf. "Applications of programmable MEMS micromirrors in laser systems." Thesis, University of Strathclyde, 2013. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=20837.
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The use of optical microelectromechanical systems (MEMS) as enabling devices has been shown widely over the last decades, creating miniaturisation possibilities and added functionality for photonic systems. In the work presented in this thesis angular vertical offset comb-drive (AVC) actuated scanning micromirrors, and their use as intracavity active Q-switch elements in solid-state laser systems, are investigated. The AVC scanning micromirrors are created through a multi-user fabrication process, with theoretical and experimental investigations undertaken on the influence of the AVC initial conditions on the scanning micromirror dynamic resonant tilt movement behaviour. A novel actuator geometry is presented to experimentally investigate this influence, allowing a continuous variation of the initial AVC comb-offset angle through an integrated electrothermal actuator. The experimentally observed changes of the resonant movement with varying initial AVC offset are compared with an analytical model, simulating this varying resonant movement behaviour. In the second part of this work AVC scanning micromirrors are implemented as active intra-cavity Q-switch elements of a Nd:YAG solid-state laser system. The feasibility of achieving pulsed laser outputs with pulse durations limited by the laser cavity and not the MEMS Q-switch is shown, combined with a novel theoretical model for the Q-switch behaviour of the laser when using a bi-directional intra-cavity scanning micromirror. A detailed experimental investigation of the pulsed laser output behaviour for varying laser cavity geometries is presented, also discussing the influence of thin film coatings deposited on the mirror surfaces for further laser output power scaling. The MEMS Q-switch system is furthermore expanded using a micromirror array to create a novel Q-switched laser system with multiple individual controllable output beams using a common solid-state gain medium. Experimental results showing the simultaneous generation of two laser outputs are presented, with cavity limited pulse durations and excellent laser beam quality.
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Krishnamoorthy, Uma. "Design and fabrication of micromirrors for optical applications /." Connect to Digital dissertations. Restricted to UC campuses. Access is free to UC campus dissertations, 2002. http://uclibs.org/PID/11984.
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Marinescu, Cristina. "A surface micromachining fabrication process for aluminium MEMS micromirrors /." Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=98996.
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This thesis focuses on the implementation of a surface micromachining fabrication process for electrostatically actuated MEMS micromirrors in the McGill University's Nanotools microfabrication laboratory. The process consists in fabricating the devices out of aluminum using photoresist as a sacrificial material. To this effect simple cantilever micromirror structures were designed. They were then modeled and simulated using finite-element analyses from the commercially-available software ANSYS. Finally, in order to validate the results of the new process, the same structures were fabricated out of polysilicon using the Multi-User MEMS Processes (PolyMUMPS) technology available through the Canadian Microelectronics Corporation (CMC). The theoretical and experimental results from the PolyMUMPS micromirrors were compared. The results at low voltages were similar, but they diverged for larger voltages and deflections, with the simulations usually predicting stiffer structures. The characterization of the structures fabricated with the Nanotools process indicated that they remained stuck to the substrate after the release process. Manipulation during testing caused some of them to be partially released, at which point they could be electrostatically actuated. With a better understanding of the aluminum properties and modifications to the original designs, one can fabricate viable aluminum structures using this process. Different areas of improvement as well as future directions for MEMS fabrication in this laboratory were also identified.
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Worapattrakul, Natalie [Verfasser]. "Micromirrors for Daylight Steering Applications : Planarization of Micromirror Planes by Sub-Structure Implementation and Process Transfer to Nanoimprint Fabrication Technology / Natalie Worapattrakul." Kassel : Kassel University Press, 2017. http://d-nb.info/1129182908/34.
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Lee, Dae Sung. "Design and fabrication of SOI-based micromirrors for optical applications /." May be available electronically:, 2007. http://proquest.umi.com/login?COPT=REJTPTU1MTUmSU5UPTAmVkVSPTI=&clientId=12498.
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Mi, Bin. "Static and Electrically Actuated Shaped MEMS Mirrors." Case Western Reserve University School of Graduate Studies / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=case1078605638.
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Kaupmann, Philip [Verfasser], Thomas [Akademischer Betreuer] Otto, Thomas [Gutachter] Otto, and Klaus-Dieter [Gutachter] Lang. "A Novel Indirect Actuation Concept for MEMS Micromirrors / Philip Kaupmann ; Gutachter: Thomas Otto, Klaus-Dieter Lang ; Betreuer: Thomas Otto." Chemnitz : Technische Universität Chemnitz, 2021. http://d-nb.info/1233426176/34.
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Lin, Julianna E. "Design and characterization of MEMS micromirror devices." Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=32964.
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This thesis explores the design, implementation and characterization of MEMS micromirror devices for use in optical systems. Possible applications for these devices include areas such as adaptive optics, beam scanning, and optical switches. The devices were fabricated using a commercial MEMS foundry process, known as the Multi-User MEMS Processes (MUMPs) foundry service; the resulting prototypes were characterized using a phase-shifting Mirau interferometer, assembled specifically for this work. From these results, it was shown that the MUMPs process can be used to create satisfactory designs for rotational micromirrors with tilt angles in the range of 0--23 mrad and control voltages in the range of 0--30 V In addition, the behaviour of these mirrors were shown to fall within 5% of the predicted values calculated by the theoretical models for the devices.
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Poyyathuruthy, Bruno Binal [Verfasser]. "Individually tunable micromirror arrays / Binal Poyyathuruthy Bruno." Düren : Shaker, 2021. http://d-nb.info/1240853599/34.
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YAN, JUN. "THREE-DIMENSIONAL DISPLAY SYSTEMS IMPLEMENTED WITH A MICROMIRROR ARRAY." University of Cincinnati / OhioLINK, 2001. http://rave.ohiolink.edu/etdc/view?acc_num=ucin997703291.
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Todd, Shane Truman. "Electrothermomechanical modeling of a 1-D electrothermal MEMS micromirror." [Gainesville, Fla.] : University of Florida, 2005. http://purl.fcla.edu/fcla/etd/UFE0008981.
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Li, Kebin. "Micromirror array phase modulator for ultrashort optical pulse shaping /." Connect to Digital dissertations. Restricted to UC campuses. Access is free to UC campus dissertations, 2002. http://uclibs.org/PID/11984.
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Hui, Jeremy R. (Jeremy Ryan) 1977. "Optical tweezers using the Texas Instruments' Digital Micromirror Device(tm)." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/86699.
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Thesis (M.Eng. and S.B.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2001.Includes bibliographical references.
by Jeremy R. Hui.
M.Eng.and S.B.
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Cho, Gyoungil. "Design, fabrication, and testing of a variable focusing micromirror array lens." Diss., Texas A&M University, 2003. http://hdl.handle.net/1969.1/2186.
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A reflective type Fresnel lens using an array of micromirrors is designed and fabricated using the MUMPs?? surface micromachining process. The focal length of the lens can be rapidly changed by controlling both the rotation and translation of electrostatically actuated micromirrors. The suspension spring, pedestal and electrodes are located under the mirror to maximize the optical efficiency. The micromirror translation and rotation are plotted versus the applied voltage. Relations are provided for the fill-factor and the numerical aperture as functions of the lens diameter, the mirror size, and the tolerances specified by the MUMPs?? design rules. Linnik interferometry is used to measure the translation, rotation, and flatness of a fabricated micromirror. The reflective type Fresnel lens is controlled by independent DC voltages of 16 channels with a 0 to 50V range, and translational and torsional stiffness are calibrated with measured data. The spot diameter of the point source by the fabricated and electrostatically controlled reflective type Fresnel lens is measured to test focusing quality of the lens.
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Heath, Daniel. "Digital micromirror devices and femtosecond laser pulses for rapid laser micromachining." Thesis, University of Southampton, 2017. https://eprints.soton.ac.uk/417275/.
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Laser machining techniques are almost ubiquitous in industry for micro- to nanoscale fabrication. It is essential for the advancement of the field that faster, cheaper processes be developed. Enhancements in speed and fidelity of production can be made to both additive and subtractive writing techniques by using Digital Micromirror Devices (DMD), particularly when coupled with femtosecond laser pulses. The objective of this thesis is the demonstration of DMDs used in conjunction with ultrafast laser pulses for both novel and rapid machining applications; primarily image-projection based techniques, using DMDs as dynamic intensity masks, will be used for subtractive patterning, laserinduced transfer, multi-photon polymerisation and centimetre-scale micro-machining. The dynamic nature of the DMD enables its application to the field of multiple exposures, and the centimetre-scale machining is applied to functional biological assays. Adaptive mask techniques are used to enhance the image reproduction achieved, correct for positional errors introduced by translation stages, as well as to attain greyscale intensity control with a DMD in single ultrashort pulses. A new technique for producing digital holograms is developed, and will form the basis of future work. Image projection-based patterning using DMDs as dynamic intensity masks is shown via ablation, multiphoton polymerisation and Laser-Induced Transfer (LIT). Ablation was achieved in a range of materials (including, but not limited to: gold, graphite, diamond, bismuth telluride and antimony telluride, glass, nickel, glucose, and gelatin), with 2 micron resolutions in samples and overall sizes of 1cm2. A multiple exposure technique reduced final structure resolution by 2.7 compared to the diffraction limit possible in a single exposure – from 1m to 370nm on one experimental setup, and from 727nm to 270nm on a second setup. The first demonstration of shaped, solid-phase LIT deposits has been made, both in forward and backward directions of transfer. Adaptive optics techniques have been developed for DMD mask corrections, and have reduced the positional error of samples introduced by translation stages. Greyscale intensity patterns have been projected at samples using the strictly binary-style DMD display technology, and the loss of intensity in high spatial frequencies at the sample has been addressed. A novel method for the generation of binary holograms is introduced, which allows for several additional degrees of control over spatial intensity patterns when using DMDs, such as the effective mask position relative to imaging optics, greyscale control, the formation of images at multiple planes, phase control, and overall lateral shifts of the intensity distribution below a single DMD pixel width.
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Profeta, Rebecca L. "Calibration Models and System Development for Compressive Sensing with Micromirror Arrays." Wright State University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=wright15160282553897.
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Smith, Braden James, and Braden James Smith. "Single Chip LIDAR with Discrete Beam Steering by Digital Micromirror Device." Thesis, The University of Arizona, 2017. http://hdl.handle.net/10150/624132.
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A novel method of beam steering that utilizes a mass-produced Digital Micromirror Device (DMD) enables a large field of view and reliable single chip Light Detection and Ranging (LIDAR). Using a short pulsed laser, the micromirrors' rotation is frozen mid-transition which forms a programmable blazed grating which efficiently redistributes the light to a single diffraction order, among several. With a nanosecond 905nm laser and Si avalanche photo diode, measurement accuracy of < 1 cm for 3340 points/sec is demonstrated over a 1 m distance range and with a 48° full field of view.
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Anderton, Blake Jerome. "Application of Digital Micromirror Devices to Atmospheric Lidar Measurement and Calibration." Diss., The University of Arizona, 2014. http://hdl.handle.net/10150/333349.
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A novel design for atmospheric laser radar (lidar) is presented, implementing a digital micromirror device (DMD) for use in (A) aligning transmitter and receiver boresight angles and in (B) field-of-view (FOV) control of such "DMD lidar" instruments. A novel technique is presented to extract the transmitter-receiver overlap-compensation function from ratioing data from different FOVs in the same pointing direction. DMD lidar design considerations and trades are surveyed. Principles of modeling DMD lidar performance are introduced and implemented in a performance-predictive system simulation with data-validated results. Operational capabilities of DMD lidar are demonstrated through a hardware prototype with field measurement examples. Additional capabilities offered by integrating DMD within lidar and other optical systems are presented, including single-pixel Radon-imaging techniques.
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Tondapu, Karthik. "Design and fabrication of one and two axis nickel electroplated micromirror array." Diss., Columbia, Mo. : University of Missouri-Columbia, 2007. http://hdl.handle.net/10355/6037.
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Thesis (M.S.)--University of Missouri-Columbia, 2007.The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on April 15, 2008) Includes bibliographical references.
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Eriksson, Ronja. "Evaluation of properties of a digital micromirror device applied for light shaping." Thesis, Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-74521.
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Wiswell, Nicholas A. "Design and Fabrication of Electrostatically Actuated Serpentine-Hinged Nickel-Phosphorous Micromirror Devices." DigitalCommons@CalPoly, 2014. https://digitalcommons.calpoly.edu/theses/1188.
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A process for micromachining of micro-mirror devices from silicon-on-insulator wafers was proposed and implemented. Test methods and force applicators for these devices were developed. Following successful fabrication of these devices, a novel process for fabrication of devices out of the plane of the silicon wafer was proposed, so that the devices could be actuated electrostatically. In particular, the process makes use of thick photoresist layers as a sacrificial mold into which an amorphous nickel-phosphorous alloy may be deposited. Ideal design of the electrostatically actuated micro-mirrors was investigated, and a final design was selected and modeled using FEA software, which found that serpentine-hinged devices require approximately 33% of the actuation force of their straight-beamed counterparts. An aqueous electroless plating solution composed of nickel acetate, sodium hypophosphite, citric acid, ammonium acetate, and Triton X-100 in was developed for use with the process, and bath operating parameters of 85°C and 4.5 pH were determined. However, this electroless solution failed to deposit in the presence of the photoresist. Several mechanisms proposed for deposition failure included leaching of organic solvents from the photoresist, oxidation of the nickel-titanium seed layer on which the deposition was intended to occur, and nonlinear diffusion of dissolved oxygen in the solution.
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McCray, David L. Jr. "The Design and Fabrication of a Low-Cost, DMD Based Projection Lithography System." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1345225235.
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Upadhyay, Vandana. "Design and fabrication of a re-configurable micromirror array for an optical microspectrometer." [Tampa, Fla.] : University of South Florida, 2005. http://purl.fcla.edu/fcla/etd/SFE0001138.
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Hoa, Xuyen D. 1976. "An investigation of a compact micro-optic and micromirror-based optical power equalizer /." Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=81539.
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This thesis examines the design and characterisation of a compact optical power equalizer module for optical fiber telecommunication applications. The various components of the modules are separately examined in terms of their impact on the overall dimension, performance and loss of the equalizer module. Two components are studied in greater details, namely the micro diffractive optical elements (DOEs), responsible for the multiplexing/demultiplexing of the wavelength channels, and the micromirrors, responsible for creating the beam displacements and thus controlling the attenuation. The DOEs allow for the spatial separation of 64 wavelengths into a two-dimensional array with a compact module. MUMPs surface-micromachined micromirrors have good optical properties: 0.29 dB (93.5%) reflectance, low surface sag and negligible curvature. At operating voltages of less than 15 V, tilts of 16 mrad are obtained, sufficient to provide over 50 dB attenuation for the equalizer. Simulation results show that the diffractive elements have low efficiency due to fabrication limitations. The power loss due to beam clipping is 2.81 dB with overall system efficiency at above 5 dB. Major areas of improvement in the device packaging, assembly and efficiency have been identified for future works.
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Li, Meiting. "Single crystal silicon Lorentz force actuated micromirror and MEMS blazed grating for optics and sensors." Elsevier, 2016. http://hdl.handle.net/1993/31649.
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Micromirrors and diffraction gratings were developed for spectroscopy and magnetic field sensor in this thesis. MEMS blazed gratings were successfully fabricated in different grating periodicities to cover a wide infrared wavelength range. Lorentz force actuated micromirrors were investigated, and two types of mirrors were fabricated: rotating and pop-up micromirrors. The deflection angle of the mirrors was controllable by altering the driving current on the mirror. Deflection angle vs. driving current was studied for different mirror types and different spring dimensions.
A Lorentz force based magnetic field sensor is also demonstrated. The sensor employs the rotating micromirror as a resonator. With an AC current flowing around the micromirror, a periodic Lorentz force is generated which drives the resonator. The rotational amplitude of the micromirror is measured with an optical positioning system and external circuits. The highest resolution of the magnetic field sensor is 0.4 nT at 50 mArms, and 53 mHz filter bandwidth. With appropriate current level, this sensor can measure a wide range of magnetic field, from nT to T.October 2016
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Chang, Won Jae. "Design and fabrication of a novel electrostatic micromirror with high speed and large rotation angle." [Gainesville, Fla.] : University of Florida, 2005. http://purl.fcla.edu/fcla/etd/UFE0009060.
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Amirazada, Muhammad Rizwan [Verfasser]. "Optimization in the Technological Steps for the Fabrication of Large Area Micromirror Arrays / Muhammad Rizwan Amirazada." Kassel : Universitätsbibliothek Kassel, 2015. http://d-nb.info/1067987800/34.
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Liang, Chao-Wen. "Phase Shifting Grating-Slit Test Utilizing A Digital Micromirror Device With an Optical Surface Reconstruction Algorithm." Diss., The University of Arizona, 2006. http://hdl.handle.net/10150/193833.
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A novel optical surface testing method termed the grating-slit test is demonstrated to provide quantitative measurements and a large dynamic measurement range. Although it uses a grating and a slit, as in the traditional Ronchi test, the grating-slit test is different in that the grating is used as the object and the slit is located at the observation plane. This is an arrangement that appears not to have been previously discussed in the optical testing literature. The grating-slit test produces fringes in accordance with the transverse ray aberrations of an aberrated wavefront. By using a spatial light modulator as the incoherent sinusoidal intensity grating it is possible to modulate the grating and produce phase shifting to make a quantitative measurement. The method becomes feasible given the superior intensity grayscale ability and highly incoherent illumination of the spatial light modulator used. Since the grating is used as the object, there are no significant diffraction effects that usually limit the Ronchi test. A geometrical and a detailed physical analysis of the grating-slit test are presented that agree in the appropriate limit. In order to convert the measured transverse ray aberrations to the surface figure error, a surface slope sensitivity method is developed. This method uses a perturbation algorithm to reconstruct the surface figure error from the measured transverse ray aberration function by exact ray tracing. The algorithm takes into account the pupil distortion and maps the transverse ray aberration from the coordinate system of the observation plane to the coordinate system of the surface under test. A numerical simulation proves the validity of the algorithm. To demonstrate the dynamic range of the grating-slit testing method, two optical surfaces are measured. The first surface is a polished spherical mirror with 0.6 waves of aberration as measured with an interferometer. Using the concept of transverse ray aberration separation, the first surface is measured without a strict alignment requirement. The second surface is a concave ground optical surface with 275 waves of astigmatism. The measurements from the grating-slit test yield useable surface figure information that is in agreement with the results from other testing methods.
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Lapisa, Martin. "Wafer-level 3-D CMOS Integration of Very-large-scale Silicon Micromirror Arrays and Room-temperature Wafer-level Packaging." Doctoral thesis, KTH, Mikro- och nanosystemteknik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-125913.
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This thesis describes the development of wafer-level fabrication and packaging methods for micro-electromechanical (MEMS) devices, based on wafer-bonding. The first part of the thesis is addressing the development of a wafer-level technology that allows the use of high performance materials, such as monocrystalline silicon, for MEMS devices that are closely integrated on top of sensitive integrated circuits substrates. Monocrystalline silicon has excellent mechanical properties that are hard to achieve otherwise, and therefore it fits well in devices for adaptive optics and maskwriting applications where nanometer precision deflection requirements call for mechanically stable materials. However, the temperature sensitivity of the integrated circuits prohibits the use of monocrystalline silicon with conventional deposition and surface micromachining techniques. Here, heterogeneous 3-D integration by adhesive wafer-bonding is used to fabricate three different types of spatial light modulators, based on micromirror arrays made of monocrystalline silicon; micromirror arrays with vertically moving “piston-type” mirrors and with tilting mirrors made of one functional monocrystalline silicon layer, and vertically moving hidden-hinge micromirror arrays made of two functional monocrystalline silicon layers. The second part of the thesis addresses the need for room-temperature packaging methods that allow the packaging of liquids or in general heat sensitive devices on wafer-level. A packaging method was developed that is based on a hybrid wafer-bonding approach, combining the compression bonding of gold gaskets with adhesive bonding. The packaging method is first demonstrated for the wafer-level encapsulation of liquids in reservoirs and then applied to packaging a dye-based photonic gas sensor.QC 20130816
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Daqaq, Mohammed F. "Adaptation of Nontraditional Control Techniques to Nonlinear Micro and Macro Mechanical Systems." Diss., Virginia Tech, 2006. http://hdl.handle.net/10919/28466.
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We investigate the implementation of nontraditional open-loop and closed-loop control techniques to systems at the micro and macro scales. At the macro level, we consider a quay-side container crane. It is known that the United States relies on ocean transportation for 95% of cargo tonnage that moves in and out of the country. Each year over six million loaded marine containers enter U.S. ports. Current growth predictions indicate that container cargo will quadruple in the next twenty years. To cope with this rapid growth, we develop a novel open-loop input-shaping control technique to mitigate payload oscillations on quay-side container cranes. The proposed approach is suitable for automated crane operations, does not require any alterations to the existing crane structure, uses the maximum crane capabilities, and is based on an accurate two-dimensional four-bar-mechanism model of a container crane. The shaped commands are based on a nonlinear approximation of the two-dimensional model frequency and, unlike traditional input-shaping techniques, our approach can account for large hoisting operations. For operator-in-the-loop crane operations, we develop a closed-loop nonlinear delayed-position feedback controller. Key features of this controller are that it: does not require major modifications to the existing crane structure, accounts for motion inversion delays, rejects external disturbances, and is superimposed on the crane operator commands. To validate the controllers, we construct a 1:10 scale model of a 65-ton quay-side container crane. The facility consists of a 7-meter track, 3.5-meter hoisting cables, a trolley, a traverse motor, two hoisting motors, and a 50-pound payload. Using this setup, we demonstrated the effectiveness of the controllers in mitigating payload oscillations in both of the open-loop and closed-loop modes of operation.
At the micro level, we consider a micro optical device known as the torsional micromirror. This device has a tremendous number of industrial and consumer market applications including optical switching, light scanning, digital displays, etc. To analyze this device, we develop a comprehensive model of an electrically actuated torsional mirror. Using a Galerkin expansion, we develop a reduced-order model of the mirror and verify it against experimental data. We investigate the accuracy of representing the mirror using a two-degrees-of-freedom lumped-mass model. We conclude that, under normal operating conditions, the statics and dynamics of the mirror can be accurately represented by the simplified lumped-mass system. We utilize the lumped-mass model to study and analyze the nonlinear dynamics of torsional micromirrors subjected to combined DC and resonant AC excitations. The analysis is aimed at enhancing the performance of micromirrors used for scanning applications by providing better insight into the effects of system parameters on the microscanner's optimal design and performance. Examining the characteristics of the mirror response, we found that, for a certain DC voltage range, a two-to-one internal resonance might be activated between the first two modes. Due to this internal resonance, the mirror exhibits complex dynamic behavior. This behavior results in undesirable vibrations that can be detrimental to the scanner performance.
Torsional micromirrors are currently being implemented to provide all-optical switching in fiber optic networks. Traditional switching techniques are based on converting the optical signal into electrical signal and back into optical signal before it can be switched into another fiber. This reduces the rate of data transfer substantially. To realize fast all-optical switching, we enhance the transient dynamic characteristics and performance of torsional micromirrors by developing a novel technique for preshaping the voltage commands applied to activate the mirror. This new approach is the first to effectively account for inherent nonlinearities, damping effects, and the energy of the significant higher modes. Using this technique, we are able to realize very fast switching operations with minimal settling time and almost zero overshoot.Ph. D.
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Berndt, Dirk. "Optische Kalibrierung von diffraktiven Mikrospiegelarrays." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-132819.
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Diffraktive Mikrospiegelarrays sind eine seit Jahren etablierte innovative Lösung zur ortsaufgelösten Beleuchtungsmodulation im UV-Spektralbereich. Sie werden hauptsächlich als Schlüsselbauelement in mikrolithografischen Industrieanlagen eingesetzt. Gegenwärtige Untersuchungen befassen sich mit der Erweiterung der Technologie hin zu multispektralen Anwendungen, beispielsweise in der Mikroskopie zur strukturierten Objektausleuchtung. Aufgrund des diffraktiven Arbeitsprinzips mit Phasenmodulationen im Nanometerbereich sowie der Vielzahl von Einzelspiegeln mit individuellem Auslenkverhalten stellt die präzise Ansteuerung der Bauelemente eine wesentliche Herausforderung dar. In diesem Kontext steht die Entwicklung und Validierung eines Verfahrens im Fokus dieser Arbeit, das die Gesamtheit von mehreren Tausend oder auch Millionen Mikrospiegeln abhängig von gewünschtem Beleuchtungsmuster und -wellenlänge auf korrekte Kippwinkel einstellen kann. Der gewählte Ansatz liegt in einem Mess- und Korrekturverfahren aller Einzelspiegelverkippungen. Die als Kalibrierung bezeichnete Methode nutzt ein Weißlichtinterferometer zur profilometrischen Charakterisierung der elektro-mechanischen Übertragungsfunktionen der Aktuatoren, wodurch erstmalig auf diesem Themengebiet der multispektrale Bauelementeinsatz gewährleistet werden kann. Zentrales Ergebnis der Kalibrierroutine ist eine Reduzierung der Streuung der Spiegelverkippungen um einen Faktor größer fünf. Direkte Folge sind erheblich verbesserte optische Projektionsmuster, aufgenommen an einem parallel entwickelten optischen Lasermessplatz mit spektral verschiedenen Quellen. Nachgewiesen wurden im Vergleich zum unkalibrierten Ausgangszustand Kontrastverdoppelungen, Homogenitätssteigerungen und die Sicherstellung der Abbildung von mindestens 64 Graustufen. Die Ergebnisse dokumentieren einerseits die Leistungsfähigkeit von diffraktiven Mikrospiegelarrays in multispektralen Umgebungen mit sehr guten Abbildungseigenschaften. Gleichzeitig konnte die wesentliche Grundlage für einen deutlich erweiterten Einsatz optischer Mikrosysteme im stark wachsenden Anwendungsbereich der diffraktiven Optik bzw. der Ultrapräzisionsoptik geschaffen werden.
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Nguyen, The Quyen. "Mise au point d'un nouveau type de spectromètre Raman basé sur l'utilisation d'un DMD, à vocation industrielle." Châtenay-Malabry, Ecole centrale de Paris, 2007. http://www.theses.fr/2007ECAP1031.
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Dans ce travail, nous avons montré la faisabilité du spectromètre Raman de nouvelle génération utilisant un DMD comme modultateur de lumière couplé avec un PM comme détecteur. Le spectromètre donne des résultts très prometteurs pour des analyses qualitatives et quantitaves. Pour les analyses qualitatives il suffit d'une seconde pour identifier un constituant dun mélange. Pour les analyses quantitatives, malgré la présence éventuelle de fluorescence dans les échantillons, les tests effectués sur des mélanges binaires et terniaires de xylènes ont montré qu'on arrive à des erreurs de prédiction d'nviron 3% pour un temps d'analyse de 5 à 6 ssecondespar échantillon. Avec un coût relativement faible, un tel spectromètre, rovuste et précis pourrait être la solution pour de nombreuses nouvelles applications industrielles pour lesquelles, il n'existe pas vraiment de matériel concurent actuellement. Les résultats d'nalyse quantitative utilisan les méthodes chimiompétriques confirment l'efficacité et la précision des méthodes "Backward stepwise selection of Peaks Intensities" (BssPI) et "Sum of Characteristic Peaks of a component" (SCPC). Ce sont des méthodes simples, facilement accessibles pour des utilisateurs non experts et qui ne demandent pas de connaissance préalable des produits analysés. Ces deux méthodes se sont montrées robustes dans des conditions physico-chimiques sévères que l'on peut rencontrer dans un environnement industriel et s'avèrent ainsi les mieux adaptées à l'analyse quantitative à l'aide d'un spectromètre Raman DMD/PMIn this work, the feasibility of combining the use of a DMD aslight modulator and a photomultiplier tube as detector in a Raman spectrometer has been demonstrated. New in conception and simple in configuration, such instruments should have production costs comsiderably lower than for traditional instrumetnts since both DMD and PTM are not expensive. With our prototype, a qualitative identification takes 1 second per product for qualitative analys and an analytical precision of -3% error can be otained in 5-6 seconds for one sample analysis, even in the present of fluorescence in samle. Thus various industrial applications become possible due to the short recording time combined with the possibilities of remot in situ measurements using optical fibers. Two methods of quantitative analysis have been proposed, "Backward stepwise selection of Peaks Intensities" (BssPI) et "Sumof Characteristic Peaks of a Component". Robust when faced to industrial conditions, they appear to be most appropriate for our analysis using ourDMD/PMT Raman spectrometer with low number of measurements and acceptable error of prediction. These two methods are pressently being used on our DMD/PMT Raman spectrometer
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Klose, Thomas. "Modellierung und Entwurf von resonanten Mikroaktoren mit elektrostatischem Antrieb." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-200907.
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Resonante Mikrobauelemente mit elektrostatischem Antrieb finden seit einigen Jahren vermehrt Anwendung in vielen Bereichen der Technik. So beruhen beispielsweise Drehraten- oder Beschleunigungssensoren, die im Automobilbau eingesetzt werden auf diesem Prinzip. Neue Anwendungsfelder ergeben sich vor allem für Aktoren, beispielsweise für die am Fraunhofer IPMS entwickelten Mikroscannerspiegel mit Out-of-plane-comb-Antrieb. Sie dienen zur geometrischen Ablenkung von Licht und können zur Realisierung von hochintegrierten Systemen zur Ausgabe (Laser-Projektor) oder Aufnahme (Laser-Imager) von Daten genutzt werden. Zum Entwurf von Mikroaktoren gibt es eine Reihe von Arbeiten, die sich meist auf ein konkretes Antriebsprinzip beziehen oder den Entwurf im Allgemeinen behandeln. Die vorliegende Arbeit verfolgt daher das Ziel, speziell die Randbedingungen beim Entwurf resonanter Mikroaktoren mit Out-of-plane-comb-Antrieb zu identifizieren bzw. zu systematisieren sowie die gewonnenen Erkenntnisse in einem effizienten Entwurfsprozess umzusetzen. Dabei sollen möglichst auch relevante nichtlineare Effekte berücksichtigt werden, sodass sich neue Möglichkeiten zur Optimierung der Bauelemente und damit zur Erweiterung des Entwurfsraums ergebenElectrostatically driven microsystems are utilized in technical systems for several years. For instance, they are used in automotive applications as acceleration sensors or angular rate sensors. New fields of applications appear especially for actuators. The scanning micromirror of the Fraunhofer Institute for Photonic Microsystems is such an actuator. It is a micro-optical-electrical microsystem (MOEMS) which is driven resonantly by an electrostatic comb drive and can be used in scanning laser imaging systems or laser projectors. Several technical and scientific publications occupy with the design and the simulation of microactuators, which refer usually to a concrete drive principle or to the issues of design in general. The intention of this thesis is to identify and systematize particularly the boundary conditions of design regarding to resonant micro actuators with out-of-planecomb drive. The findings are implemented in efficient design tools and design processes. One emphasis thereby is the investigation of nonlinear properties and effects. This includes geometrically non-linearities of suspensions as well as non-linearities caused by fluid damping and the electrostatic comb drive. The findings are utilized in an analytical, nonlinear stability analysis of the device's equation of motion as well as in an object oriented software library for the MATLAB environment, which can be used to create nonlinear reduced order models of scanning micromirrors. With the developed techniques for design and optimization the available parameter range of scanning micromirrors can be extended. By that means, it is possible to improve the properties of existing devices as well as create new devices with outreaching performance
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葉志賢. "Feedback Control of Torsional Micromirrors." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/04038345478144061260.
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Chen, Jung-Sheng, and 陳榮陞. "Modeling for Electrostatic Torsional Micromirrors." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/00787743804451267478.
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碩士國立中興大學
應用數學系
92
In this paper, a new analytical model is presented to describe the static behavior of an electrostatically-actuated torsional micromirror based on the parallel-plate capacitor model. In the past study, only the torsional effect of a torsional beam is considered in an analytic model of the micromirror. The vertical deflection of the torsional beam is neglected unless a complex and time-consuming finite element analysis is used. In our study, both torsional effect and vertical deflection effect are considered. It is found that the vertical displacement vs. driving voltage curves and rotation angle vs. driving voltage curves are in good agreement with those found by a popular finite element solution technique — ANSYS. In additions, figures of showing relations between rotation angle and driving voltage using various stiffness ratio and different sizes of electrodes are presented.
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Bhaskar, Avinash Kuppar. "Synthesis of electrostatically actuated optical micromirrors." Thesis, 2004. http://spectrum.library.concordia.ca/8241/1/MR04414.pdf.
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Micro Electro Mechanical Systems (MEMS) or Micro System Technology (MST) has gained a lot of focus in recent years from technologists, as it has evolved as a promising technology having applications in diverse fields such as telecommunications and medicine. Synthesis of one of the micro devices namely, the torsional micromirror that falls under the sub-category of Micro Opto Electro Mechanical Systems (MOEMS) is studied in this thesis. Synthesis involves the comprehensive design, fabrication of micromirrors validated with testing in the present work. The synthesis is carried out in the presence of electrostatic effects on micromirrors. In the present work the effect of main and counter electrostatic fields on 90{493} and one dimensional scanning micromirrors are analyzed. In the case of 90{493} mirror, a stopper is introduced whose electrostatic field improves the tilting angle by increasing the net electrostatic force acting on the micromirror. (Abstract shortened by UMI.)
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You, Jianliang. "Compliant Torsional Micromirrors with Electrostatic Actuation." Thesis, 2012. http://spectrum.library.concordia.ca/973562/1/You_PhD_S2012.pdf.
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Due to the existence of fabrication tolerance, property drift and structural stiction in MEMS (Micro Electro Mechanical Systems), characterization of their performances through modeling, simulation and testing is essential in research and development. Due to the microscale dimensions, MEMS are more susceptible and sensitive to even minor external or internal variations. Moreover, due to the current limited capability in micro-assembly, most MEMS devices are fabricated as a single integrated micro-mechanical structure composed of two essential parts, namely, mass and spring, even if it may consist of more than one relatively movable part. And in such a scale of dimensions, low resonant micro-structures or compliant MEMS structures are hard to achieve and difficult to survive. Another problem arises from the limited visibility and accessibility necessary for characterization. Both of these issues are thus attempted in this research work.
An investigation on micromirrors with various actuations and suspensions is carried out, with more attention on the micromirrors with compliant suspensions, electrostatic actuation and capable of torsional out-of-plane motion due to their distinct advantages such as the low resonance and the low drive voltage. This investigation presents many feasible modeling methods for prediction and analysis, aiming to avoid the costly microfabrication. Furthermore, both linear and nonlinear methods for structure and electrostatics are all included. Thus, static and dynamic performances of the proposed models are formularized and compared with those from FEA (Finite Element Analysis) simulation. The nonlinear modeling methods included in the thesis are Pseudo Rigid Body Model (PRBM) and hybrid PRBM methods for complex framed microstructures consisting of compliant beam members.
The micromachining technologies available for the desired micromirrors are reviewed and an SOI wafer based micromachining process is selected for their fabrication. Though the fabrication was executed outside of the institution at that time, the layout designs of the micro-chips for manufacture have included all related rules or factors, and the results have also demonstrated the successful fabrication.
Then investigation on non-contact test methods is presented. Laser Doppler Vibrometer (LDV) is utilized for the measurement of dynamic performances of proposed micromirrors. Two kinds of photo-sensing devices (PSDs), namely, the digitized PSD formed by CCD arrays and the analog PSD composed of a monolithic photosensing cell, are used for static test set-ups. An interferometric method using Mirau objective along with microscope is also employed to perform static tests of the selected micromirrors. Comparison of the tested results and their related theoretical results are presented and discussed, leading to a conclusion that the proposed hybrid PRBM model are appropriate for prediction or analysis of compliantly suspended micromirrors including issues arising from fabrication tolerance, structural or other parametric variations.
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Morrison, Jessica. "Statics and dynamics of electrothermal micromirrors." Thesis, 2016. https://hdl.handle.net/2144/19758.
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Adaptive and smart systems are growing in popularity as we shift toward personalization as a culture. With progressive demands on energy efficiency, it is increasingly important to focus on the utilization of energy in a novel way. This thesis investigates a microelectromechanical system (MEMS) mirror with the express intent to provide flexibility in solid state lighting (SSL). By coupling the micromirror to an optical source, the reflected light may be reshaped and directed so as to optimize the overall illumination profile. In addition, the light may be redirected in order to provide improved signal strength in visible light communications (VLC) with negligible impact on energy demands.
With flexibility and full analog control in mind, the design of a fully integrated tip-tilt-piston micromirror with an additional variable focus degree of freedom is outlined. Electrothermal actuators are used to both steer the light and tune the focal length. A detailed discussion of the underlying physics behind composite beams and thermal actuators is addressed. This leads directly into an overview of the two main mirror components, namely the segmented mirror and the deflection actuators.
An in-depth characterization of the dynamics of the mirror is discussed including the linearity of the thermal response. Frequency domain analysis of such a system provides insight into tunable mechanical properties such as the resonant frequency and quality factor. The degenerate resonant modes can be separated significantly. It is shown that the frequency response may be tuned by straining specific actuators and that it follows a predictable pattern. As a result, the system can be scanned at increasingly large angles. In other words, coupled mechanical modes allow variable damping and amplification. A means to determine the level of coupling is examined and the mode shape variations are tracked as a function of the tuning parameters.
Finally, the applications of such a device are explored and tested. Such applications include reliable signal-to-noise ratio (SNR) enhancements in VLC of 30 dB and color tunable steerable lights using laser diodes. A brief discussion of the implications of dynamic illumination and tunable systems is juxtaposed with an explanation behind the integration of an electrothermal micromirror and an all digital driver.
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Yen, Han-chee, and 顏瀚琦. "Analysis and Fabrication of Deformable Focusing Micromirrors." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/21192604489223083656.
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碩士國立清華大學
動力機械工程學系
88
Micro-Electro-Mecha-Optical system, aiming at optical applications in MEMS, uses deformable mirrors to conduct adaptive optics devices and to change the focal length of the mirror. This thesis designed multi-layer deformable micromirrors with electrostatic actuation to adjust the focal length based on surface micromachining. The content of this thesis can be separated into two parts: analysis and fabrication. In analysis, plate and shell theories are used to obtain the relations among deformation, thermal stress, and applied voltage. A series of simulations, by using IntelliSuite, are performed to investigate the process- and voltage-induced deformation under various parameters for a focusing micro-mirror. Robust designs are obtained by using Taguchi method. The aim of simulations is to provide the characteristics of variables for the device, which may help the designers for choosing better parameters when fabricated. In fabrication, sectored structures with 500 um diameters are fabricated successfully. Curvature radius is measured which is about 400 um.
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鍾興宜. "Analysis and Control of Vertically Combdrive-Actuated Micromirrors." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/94888967462897429654.
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李建明. "Capacitive Feedback Control of Vertical Comb-driven Micromirrors." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/77498450442886832276.
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Kaupmann, Philip. "A Novel Indirect Actuation Concept for MEMS Micromirrors." 2019. https://monarch.qucosa.de/id/qucosa%3A74519.
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Scannende MEMS-Mikrospiegel stellen eine vielversprechende technologische Entwicklung mit potentiellen Anwendungen im Bereich der miniaturisierten Bildprojektion und Umgebungssensierung dar. Im Regelfall oszilliert das Spiegelelement hierbei resonant um die horizontale Achse, während die vertikale Achse statisch ausgelenkt wird. Somit ergibt sich ein sogenannter Raster-Scan. Während eine resonante Aktuierung in MEMS-Technologie im Frequenzbereich mehrerer kHz effizient umgesetzt werden kann, stellt die Implementierung statischer Antriebe eine Herausforderung dar. In dieser Arbeit wird ein neuartiges Aktuierungskonzept vorgestellt, das effizientere quasi-statische Auslenkung ermöglicht. Hierfür wird der Drehimpuls, der durch die hochfrequente horizontale Schwingung erzeugt wird, durch eine weitere resonante Oszillation ähnlicher Frequenz gestört, wodurch sich ein für die quasi-statische Auslenkung nutzbares Drehmoment ergibt.
Da gyroskopische Effekte ausgenutzt werden, die nicht in aktuellen auf Modalanalyse basierenden Simulationsmethoden berücksichtigt sind, werden Starrkörper- und transiente FEM-Modelle entwickelt, um die Realisierbarkeit des Antriebskonzepts simulatorisch zu verifizieren.
Im Rahmen der durch den genutzten Prozess gegebenen Randbedingungen werden daraufhin Aktuierungselemente für die resonanten Achsen erarbeitet und mit diesen zwei Designvarianten eines 2D-Mikrospiegels erstellt. Nach modellbasierter Verifikation werden diese in einer MEMS-Fertigungslinie prozessiert.
Mit den generierten Mustern wird dann eine vollständige experimentelle Charakterisierung unter Nutzung eines speziell erstellten FPGA-basierten Evaluations-Boards durchgeführt. Beide Design-Varianten zeigen hierbei voll funktionsfähige Sensierungs- und Aktuierungselemente. Es kann ein erfolgreicher Nachweis der Funktionsfähigkeit des neuartigen Antriebskonzepts vollbracht werden. Die dabei gezeigte 2D-Projektion erreicht Winkel von 12° x 1.8°Scanning MEMS micromirrors are an emergent technology for compact form factor image projection and environment sensing applications. Commonly the mirror element oscillates resonantly along the horizontal axis, whereas it is deflected statically along the vertical axis, performing a so called raster scan. While resonant actuation can be implemented efficiently in MEMS, static deflection however remains challenging. In this thesis a novel actuation concept for 2D MEMS micromirrors is introduced that potentially enables efficient quasi-static actuation. Therefore the angular momentum that is generated by the high frequency resonant axis is disturbed by an orthogonal resonant oscillation of similar frequency, leading to a torque that can be utilized to achieve an indirect quasi-static deflection. As in this case gyroscopic effects are exploited that are usually not considered in state of the art modal finite element based MEMS simulation, in order to validate the feasibility of the actuation concept rigid body and transient finite element based models are developed and simulation studies conducted. Using an existing manufacturing process as a framework, actuation schemes for the resonant axes are introduced and two distinct micromirror designs are developed and verified by simulation. These are processed in a MEMS manufacturing line. A thorough characterization study is then carried out using a custom FPGA based evaluation board with closed loop control capabilities. Both design variants are functional with regard to all actuation and tilt angle detection elements. A successful implementation of the proposed actuation concept is shown achieving 2D projection of a laser beam with tilt angles of 12 ◦ × 1.8 ◦ in frequency and amplitude controlled operation.
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Tsung-Chan, Tsai. "Design and Control of Two-Dimensional Vertical Comb-Drive Micromirrors in an Optical-Tweezers System." 2006. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0016-1303200709325446.
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Tsai, Tsung-Chan, and 蔡宗展. "Design and Control of Two-Dimensional Vertical Comb-Drive Micromirrors in an Optical-Tweezers System." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/81069871677166775880.
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碩士國立清華大學
動力機械工程學系
94
In this thesis, a novel CMOS two-dimensional (2-D) octagonal angular vertical comb-drive (AVC) micromirror is designed and fabricated for the application in a micromirror-based optical-tweezers system. The CMOS 2-D micromirror has the advantages of low cost, high fill factor, and capability of integration with readout circuit. According to the analysis, the proposed mirror has larger rotation angles, compared to the conventional rectangular staggered vertical comb-drive (SVC) micromirror. Rotation angles of ±2.1° and ±1.8° with respect to the mirror- and gimbal- axis can be achieved in this AVC octagonal 2-D micromirror. In addition, the controller, combining adaptive control and sliding control, is designed to compensate the nonlinear torque and the parametric uncertainties of the vertical comb-drive micromirror. The numerical simulation results show that the micromirror can follow the desired trajectory of 10-Hz sinusoid with tracking error of less than 0.001° in 0.01 seconds. Finally, an image processing interface is realized for cell recognition. The proposed micromirror, the nonlinear controller and the designed interface are integrated into the optical-tweezers system in application of cell manipulation and tissue construction.
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Knoernschild, Caleb. "Scalable Optical MEMS Technology for Quantum Information Processing." Diss., 2011. http://hdl.handle.net/10161/3846.
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Among the various physical systems considered for scalable quantum information processing (QIP), individually trapped ions or neutral atoms have emerged as promising candidates. Recent experiments using these systems have demonstrated the basic building blocks required for a useful quantum computer. In many of these experiments, precisely tuned lasers control and manipulate the quantum bit (qubit) represented in the electronic energy levels of the ion or atom. Scaling these systems to the necessary number of qubits needed for meaningful calculations, requires the development of scalable optical technology capable of delivering laser resources across an array of ions or atoms. That scalable technology is currently not available.
In this dissertation, I will report on the development, design, characterization, and implementation of an optical beam steering system utilizing microelectromechanical systems (MEMS) technology. Highly optimized micromirrors enable fast reconfiguration of multiple laser beam paths which can accommodate a range of wavelengths. Employing micromirrors with a broadband metallic coating, our system has the flexibility to simultaneously control multiple beams covering a wide range of wavelengths.
The reconfiguration of two independent beams at different wavelengths (780 and 635 nm) across a common 5x5 array of target sites is reported along with micromirror switching times as fast as 4 us. The optical design of the system minimizes residual intensity at neighboring sites to less than 40 dB below the peak intensity. Integration of a similar system into a neutral atom QIP experiment is reported where 5 individually trapped atoms are selectively manipulated through single qubit rotations with a single laser source. This demonstration represents the first application of MEMS technology in scalable QIP laser addressing.
Dissertation
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Kumar, Karthik. "Microelectromechanical handheld laser-scanning confocal microscope: application to breast cancer imaging." 2009. http://hdl.handle.net/2152/6974.
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Demographic data indicate that 60% of 6.7 million annual global cancer mortalities and 54% of 10.8 million new patients are in developing nations, unable or unwilling to avail of invasive screening tests that are the current norm. For most cancers, survival rate is strongly dependent on early detection, highlighting the need for improved screening methods. Studies have shown that cancers can be identified based on distinct sub-cellular morphological features and expression levels of specific molecular markers. Since 85% of cancers are known to originate in the epithelium, portable in vivo imaging techniques providing sub-cellular detail in tissue up to depths of 250 μm could help improve access to biopsy-free examination in low-infrastructure environments. The resultant early detection could dramatically improve patient prognosis, while reducing screening costs, treatment delay, and occurrences of unnecessary and potentially harmful medication. This dissertation investigates handheld instrumentation for laser-scanning confocal microscopy (LSCM) and its applicability to breast cancer detection and subsequent image-guided management. LSCM allows high-resolution mapping of spatial variations in refractive index or tumor marker expression within a single cell layer situated few hundred micrometers beneath the tissue surface. The main challenge facing miniaturization lies in the mechanism of beam deflection across the sample. The first part of the dissertation presents a fast, large-angle, high-reflectivity two-axis vertical comb driven silicon micromirror fabricated by a novel method compatible with complementary metal-oxide-semiconductor processing employed in the semiconductor industry. The process enables integration of rotation sensors on the chip to adaptively correct for aberrations in beam scanning while significantly reducing fabrication costs and barriers to market acceptance. The second part of the dissertation explores the integration of this micromirror with other optical and electronic components into a handheld laser-scanning confocal microscope. Applicability of the probe to epithelial breast cancer screening via reflectance and fluorescence imaging is investigated. Finally, enhanced imaging modalities based on the micromirror are presented. 3D cellular-level in vivo imaging via rapid swept-source optical coherence tomography is demonstrated. A method for “objective-less” microendoscopy, potentially resulting in substantially reduced probe dimensions, employing reflective binary-phase Fresnel zone plates monolithically integrated on the surface of the micromirror is presented.text
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Liu, Chun-Kai, and 劉醇鎧. "Study on electrostatic vibrational micromirror." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/38063108652249521933.
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碩士國立交通大學
光電工程所
87
In this thesis, we study on the fabrication of an electrostatic vibrational micromirror. Based on Si (111) front-side anisotropic etching technique of micromachining, we can fabricate a floating membrane of shallow gap. The membrane consists of the major structural layer of silicon rich nitride and the electrode layer of metals. When a potential difference is applied to the metal-electrode and the substrate, mechanical deformation such as displacement and tilt of the membrane results from the creating of an electrostatic force, and then the device vibrates. According to the difference of the shapes of membrane and metal-electrode, we can divide the fabricated devices into two operating modes, vertically vibrational micromirror and torsionally vibrational micromirror. In optical measurement, the former has a 1.9μm vertical displacement as a 100Volt voltage is applied. The latter has a tilt of either +2 degrees or —2 degrees as the same voltage is applied, and we obtain its first resonance frequency at about 16.5KHz. At last, we discuss what problems we experience and how to improve in fabrication process.