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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

INVESTIGATION OF THE STATIC AND DYNAMIC BEHAVIOR OF A MICRO MIRROR

Ilyas, Saad 11 1900 (has links)
This dissertation presents the modeling, design, fabrication, and experimental testing of a polyimide based micro mirror for applications in MEMS logic devices based on its static behavior and in MEMS resonators using mixed frequency excitation. First, a universal MEMS logic device that can perform all the logic operations, such as INVERTER, AND, NAND, NOR, and OR gates using one physical structure, within an operating range of 0-10 volts. It can also perform XOR and XNOR with one access inverter using the same structure with different electrical interconnects. We discuss the fabrication, simulations and experimental results demonstrating these logic operations on a polyimide micro mirror. The device is capable of performing the switching operation with a frequency of 1 kHz, a switching time of 8.2 μs, and an electrical lifetime of 8000 cycles. Second, this study presents an experimental and theoretical investigation of a micro mirror under a mixed frequency signal composed of two harmonic AC sources. The experimental and theoretical dynamics are explored via frequency sweeps in the desired neighborhoods. One frequency is fixed while the other frequency is swept through a wide 5 range to study the dynamic responses of the micro mirror. These responses are studied under different frequencies and different input voltages. The results show interesting dynamics, where the system exhibits primary resonance, and combination resonances of additive and subtractive type. The mixed excitation is demonstrated as a way to increase the bandwidth of the resonator near primary resonance, which can be promising for resonant sensing applications in the effort to increase the signal-noise ratio over extended frequency range. It can be promising for energy harvesting as well; since it provides the system with resonances of very high amplitudes at very low frequencies regardless of what is the natural frequency of the system, however this still needs further investigation.
2

INTEGRATING BEHAVIORAL MODELING AND SIMULATION FOR MEMS COMPONENTS INTO CAD FOR VLSI

GIBSON, DENNIS 16 September 2002 (has links)
No description available.
3

THREE-DIMENSIONAL DISPLAY SYSTEMS IMPLEMENTED WITH A MICROMIRROR ARRAY

YAN, JUN 11 October 2001 (has links)
No description available.
4

Quasistatisch auslenkbarer Kippspiegel zur Ablenkung von Licht / Quasistatic deflectable torsional micro mirror for light steering application

Kießling, Torsten 21 February 2008 (has links) (PDF)
This dissertation concerns quasistatic torsional mirror's for optical applications. The intended main area of application is the use as switch in optical network's, replacing the conventional optical-electro-optical conversation. With these actuator's a new concept of electrostatic actuation has been realised. While the drive electrodes are integrated into the deflectable mirror, the whole counter electrode below the mirror plate remains at equal ground potential. The device is manufactured out of two parts using method's of silicon bulk mikro machining. A deflectable mirror plate, torsional spring's and the surrounding support structure are fabricated within the thin device layer at the top of BSOI material. The counter electrode is manufactured out of a highly doped silicon wafer. Both part's are assembled together by adhesive bonding at die level at the end. Since the driving potential is supplied to the mirror plate and the counter electrode is at ground level, lateral tolerances because of device assembly mismatches does not appear with the use of the new concept. In detail the mirror plate itself is divided into two seperate electrodes by a parallel arrangement of filled isolating trenches. The highly doped device layer provides electrical connection via the torsional spring's to the mirror electrodes. A quasistatic torsional actuation is performed if a dc-voltage is applied between one mirror side and the counter electrode. Several design's have been fabricated. The lateral dimension of the torsional mirror plate vary from 0,5 mm to 2,0 mm. The designed characteristic frequencies vary from 0,5 to 3 kHz. For quasistatic actuation the pull in angle vary from 1 to 5 degree and the pull in voltage goes up to several hundred volts. Accessorily the mirror plate is enclosed by a comb drive structure. So that the device could be used for low voltage resonant actuation or an capacitive position read out becomes feasible. Within this thesis the new concept has been verified and functionality has been demonstrated. Depending on their characteristic frequency, devices are suitable to perform quasistatic actuation within 10 ms. Experiments indicated that the electrical isolation damages irreversible at drive voltage's above 400 volt. It limits the maximum deflection of nearly all design's. At prototype actuators repeatability has been studied. No drift was observed in the static characteristic within several cycles for certain designs. Closed-loop position control is not mandatory for the actuators fabricated within this thesis. Mechanical stress inside the mirror plate causes deformation of the reflective surface larger than permitted by optical criteria. This paves the way for further device optimization, yield improvement and system integration.
5

Apport de la combinaison de méthodes de mesure de formes tridimensionnelles dans le contexte de l'endoscopie flexible / Contribution of the combination of methods for three-dimensional shapes measurements in the context of flexible endoscopy

Hou, Yingfan 27 January 2016 (has links)
Les techniques de reconstruction de formes tridimensionnelles sont très largement utilisées dans de nombreux domaines, et notamment dans le domaine industriel ou médical. Et dans ces domaines, les techniques de mesure sans contact sont particulièrement étudiées, principalement parce qu'elles permettent de ne pas détériorer l'objet mesuré. Ce travail de thèse se place donc dans ce contexte et plus particulièrement dans le cas des dispositifs endoscopiques de mesure tridimensionnelle de surface par moyen optique. Dans le domaine médical, ce type d'instrument peut être appliqué à la coloscopie 3D ou à la chirurgie mini-invasive pour la détection de forme en surface de tissus biologiques. Dans cette thèse ce sont plus particulièrement les méthodes à base de stéréovision active ou passive, qui vont être étudiées et intégrées dans un dispositif miniaturisé. Différents modes de mesure vont être intégrés simultanément dans un unique instrument miniaturisé afin de permettre d'augmenter les performances de mesure : l'instrument peut adapter son principe de mesure à la texture de l'objet ou également à l'orientation des surfaces mesurées et plus généralement au contexte de la mesure. Ce travail de thèse est donc basé sur une étude algorithmique et instrumentale d'intégration de ces différents modes de mesure dans un unique instrument endoscopique miniaturisé. L'étude des modes de mesure par stéréovision a été réalisée en trois phases. Tout d'abord, c'est l'influence de l'orientation de la surface des objets mesurés dans un cas de stéréovision active qui est analysé. Puis une technique de basculement entre les voies de projection et d'acquisition du système de stéréovision active par actionnement bistable est proposé, ce qui permet d'adapter la mesure à l'orientation des surfaces à mesurer. Enfin, l'étude est orientée vers la possibilité de basculer d'un mode de stéréovision active vers un mode de stéréovision passive, toujours par actionnement bistable, le mode de stéréovision passive étant particulièrement adapté aux objets fortement texturés. Ainsi, trois modes de mesure sont réalisés dans ce nouveau système : deux modes de stéréovision active (avec inversion des voies de capture et de projection) et un mode de stéréovision passive. Pour réaliser la reconstruction tridimensionnelle, deux méthodes actives (par décalage de phase et par transformation de Fourier) et une méthode passive sont étudiées. Différentes performances de mesure sont obtenues selon les méthodes sélectionnées : un résultat de mesure plus précis est obtenu par les méthodes à. décalage de phase, une vitesse de mesure plus élevée est obtenu par les méthodes à transformée de Fourier ou par les méthodes passives. Le développement instrumental est également décrit dans cette thèse. Après modélisation optique et conception mécanique du système de mesure, un prototype de l'instrument endoscopique est fabriqué avec divers équipements spécifiques, tels qu'un DMD (Digital Micromirror Device), des guides d'images et des actionneurs électromagnétiques bistables. La validation expérimentale de la mesure tridimensionnelle est réalisée essentiellement sur objets mécaniques (du type mesure de détails sur pièce de monnaie), les deux méthodes actives et la méthode passives sont ainsi testées et confrontées. Enfin, une mesure sur un colon artificiel est réalisée par ce système pour se placer dans un contexte applicatif médical. / The techniques of three dimensional shapes reconstruction are widely used in many fields, particularly in the industrial or medical field. And in these areas, non-contact measurement techniques are particularly studied, mainly because they don't damage the measured object. This work therefore falls within this context and in particular in the case of endoscopic devices of surface coordinate measuring by optical methods. ln the medical field, this type of instrument can be applied to 3D colonoscopy or minimally invasive surgery to the surface in the form of biological tissues. In this thesis, methods based on active or passive stereo vision are the principle, which will be studied and integrated into a miniaturized device. Different measurement modes will be incorporated simultaneously into a single miniaturized instrument to help increase measurement performance: the instrument can adjust its measurement principle to the texture of the object or also to the orientation of measured surfaces more generally to the context of the measurement. This thesis is based on an algorithmic study and instrumental integration of these different measurement modes into a single miniaturized endoscopic instrument. The study of the measurement modes stereovision was conducted in three phases. First, it is the influence of the orientation of the measured objects' surface in a case of active stereovision being analyzed. And a technique of switching between the projection and acquisition in an active stereovision system by bistable actuation is proposed, which allows to adapt the measurement to the orientation of the measured surfaces. Finally, the study is oriented towards the ability to switch from one active stereovision mode to one passive stereovision mode, always by bistable actuator operation, the passive stereovision mode is particularly suitable for highly textured objects. Thus, three measurement modes are made in the new system: two modes of active stereovision (reversing capture and projection channels) and a mode of passive stereovision. To achieve three-dimensional reconstruction, two active methods (phase shift and Fourier Transform) and a passive method are studied. Different performance measurements are obtained according to methods selected: a more accurate measuring result is obtained by the phase shift methods; a high measurement speed is obtained by the Fourier transform methods or by passive methods. The instrumental development is also described in this thesis. After optical modeling and mechanical design of the measuring system, a prototype of the endoscopic instrument is manufactured with various specific devices such as a DMD (Digital Micromirror Deviee),images guides and bistable electromagnetic actuators. The experimental validation of the three-dimensional measurement is performed mainly on mechanical objects (such as details measurement on a coin), both active and passive method methods are well tested and compared. Finally, an artificial colon is measured by this system to be placed in a medical application context.
6

Quasistatisch auslenkbarer Kippspiegel zur Ablenkung von Licht

Kießling, Torsten 20 November 2007 (has links)
This dissertation concerns quasistatic torsional mirror's for optical applications. The intended main area of application is the use as switch in optical network's, replacing the conventional optical-electro-optical conversation. With these actuator's a new concept of electrostatic actuation has been realised. While the drive electrodes are integrated into the deflectable mirror, the whole counter electrode below the mirror plate remains at equal ground potential. The device is manufactured out of two parts using method's of silicon bulk mikro machining. A deflectable mirror plate, torsional spring's and the surrounding support structure are fabricated within the thin device layer at the top of BSOI material. The counter electrode is manufactured out of a highly doped silicon wafer. Both part's are assembled together by adhesive bonding at die level at the end. Since the driving potential is supplied to the mirror plate and the counter electrode is at ground level, lateral tolerances because of device assembly mismatches does not appear with the use of the new concept. In detail the mirror plate itself is divided into two seperate electrodes by a parallel arrangement of filled isolating trenches. The highly doped device layer provides electrical connection via the torsional spring's to the mirror electrodes. A quasistatic torsional actuation is performed if a dc-voltage is applied between one mirror side and the counter electrode. Several design's have been fabricated. The lateral dimension of the torsional mirror plate vary from 0,5 mm to 2,0 mm. The designed characteristic frequencies vary from 0,5 to 3 kHz. For quasistatic actuation the pull in angle vary from 1 to 5 degree and the pull in voltage goes up to several hundred volts. Accessorily the mirror plate is enclosed by a comb drive structure. So that the device could be used for low voltage resonant actuation or an capacitive position read out becomes feasible. Within this thesis the new concept has been verified and functionality has been demonstrated. Depending on their characteristic frequency, devices are suitable to perform quasistatic actuation within 10 ms. Experiments indicated that the electrical isolation damages irreversible at drive voltage's above 400 volt. It limits the maximum deflection of nearly all design's. At prototype actuators repeatability has been studied. No drift was observed in the static characteristic within several cycles for certain designs. Closed-loop position control is not mandatory for the actuators fabricated within this thesis. Mechanical stress inside the mirror plate causes deformation of the reflective surface larger than permitted by optical criteria. This paves the way for further device optimization, yield improvement and system integration.
7

Out-of-Plane Mirrors for Single-Mode Polymeric RDL using Direct Laser Writing

Mistry, Akash, Weyers, David, Nieweglowski, Krzysztof, Bock, Karlheinz 14 November 2023 (has links)
The growing demand for the Internet of Things (IoT) and Artificial Intelligence (AI) need high-speed commu-nication within short-range distances. In the Back-End-Of-Line (BEOL), Single-Mode Waveguide (SMW) with micro-mirror shows the promising application as an Optical Redistribution Layer (O-RDL) connecting photonic-chip at the interposer-level. The presented study shows the potential application of the 2-Photon-Polymerization (2PP) process for fabrication of out-of-plane coupling elements (micro-mirror) for SMW using low-loss Ormocer® hybrid polymers. This fabricated micro-mirror uses as a coupling element to connect the light from RDL to chips or for inter-layer connections at Interposer level. To evaluate the processing time, structural quality, and resolution of the printed micro-mirror, two types of lenses (63x and 25x) and Ormocer® polymers (OrmoComp and OrmoCore) were used. The optimization of the process flow for the micro-mirrors for SMW applications will be described in detail.
8

MEMS-Laser-Display-System / MEMS Laser Display System

Specht, Hendrik 19 October 2011 (has links) (PDF)
In der vorliegenden Arbeit werden die im Zusammenhang mit der Strahlablenkung stehenden Systemaspekte der auf MEMS-Scanner basierenden Laser-Display-Technologie theoretisch analysiert und aus den Ergebnissen die praktische Implementierung eines Laser-Display-Systems als Testplattform vorgenommen. Dabei werden mit einem Ansatz auf Basis zweier 1D-Scanner und einem weiteren Ansatz mit einem 2D-Scanner zwei Varianten realisiert. Darüber hinaus erfolgt die Entwicklung eines bildbasierten Multiparametertestverfahrens, welches sowohl für den Test komplettierter Strahlablenkeinheiten bzw. Projektionsmodule als auch zum umfassenden und zeiteffizienten Test von MEMS-Scannern auf Wafer-Level geeignet ist. Mit diesem Verfahren erfolgt eine Charakterisierung der zwei realisierten Varianten des Laser-Displays. Ausgehend von den Eigenschaften des menschlichen visuellen Systems und den daraus resultierenden Anforderungen an das Bild sowie einer systemtheoretischen Betrachtung des mechanischen Verhaltens von MEMS-Scannern bildet die Ansteuersignalerzeugung für den resonanten Betrieb der schnellen und den quasistatischen Betrieb der langsamen Achse einen Schwerpunkt. Neben dem reinen digitalen Regler- bzw. Filterentwurf sowie mehreren Linearisierungsmaßnahmen beinhaltet dieser auch die Herleitung einer FPGA-basierten Videosignalverarbeitung zur Konvertierung von Scannpattern, Zeitregime und Auflösung mit einer entsprechenden Synchronisierung von Strahlablenkung und Lasermodulation. Auf Grundlage der daraus resultierenden Erkenntnisse über den Zusammenhang zwischen Scanner-/Systemparametern und Bildparametern werden Testbild-Bildverarbeitungsalgorithmus-Kombinationen entwickelt und diese, angeordnet in einer Sequenz, mit einem Kalibrierverfahren zu einem Testverfahren für MEMS-Scanner vervollständigt. Die Ergebnisse dieser Arbeit entstanden im Rahmen von industriell beauftragten F&E-Projekten und fließen in die andauernde Fortführung des Themas beim Auftraggeber ein.
9

MEMS-Laser-Display-System: Analyse, Implementierung und Testverfahrenentwicklung

Specht, Hendrik 20 May 2011 (has links)
In der vorliegenden Arbeit werden die im Zusammenhang mit der Strahlablenkung stehenden Systemaspekte der auf MEMS-Scanner basierenden Laser-Display-Technologie theoretisch analysiert und aus den Ergebnissen die praktische Implementierung eines Laser-Display-Systems als Testplattform vorgenommen. Dabei werden mit einem Ansatz auf Basis zweier 1D-Scanner und einem weiteren Ansatz mit einem 2D-Scanner zwei Varianten realisiert. Darüber hinaus erfolgt die Entwicklung eines bildbasierten Multiparametertestverfahrens, welches sowohl für den Test komplettierter Strahlablenkeinheiten bzw. Projektionsmodule als auch zum umfassenden und zeiteffizienten Test von MEMS-Scannern auf Wafer-Level geeignet ist. Mit diesem Verfahren erfolgt eine Charakterisierung der zwei realisierten Varianten des Laser-Displays. Ausgehend von den Eigenschaften des menschlichen visuellen Systems und den daraus resultierenden Anforderungen an das Bild sowie einer systemtheoretischen Betrachtung des mechanischen Verhaltens von MEMS-Scannern bildet die Ansteuersignalerzeugung für den resonanten Betrieb der schnellen und den quasistatischen Betrieb der langsamen Achse einen Schwerpunkt. Neben dem reinen digitalen Regler- bzw. Filterentwurf sowie mehreren Linearisierungsmaßnahmen beinhaltet dieser auch die Herleitung einer FPGA-basierten Videosignalverarbeitung zur Konvertierung von Scannpattern, Zeitregime und Auflösung mit einer entsprechenden Synchronisierung von Strahlablenkung und Lasermodulation. Auf Grundlage der daraus resultierenden Erkenntnisse über den Zusammenhang zwischen Scanner-/Systemparametern und Bildparametern werden Testbild-Bildverarbeitungsalgorithmus-Kombinationen entwickelt und diese, angeordnet in einer Sequenz, mit einem Kalibrierverfahren zu einem Testverfahren für MEMS-Scanner vervollständigt. Die Ergebnisse dieser Arbeit entstanden im Rahmen von industriell beauftragten F&E-Projekten und fließen in die andauernde Fortführung des Themas beim Auftraggeber ein.

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