Download or read book MEMS Based Optical Coherence Tomography Imaging written by Jingjing Sun and published by . This book was released on 2012 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt: Optical coherence tomography (OCT) can provide subsurface cross-sectional information of tissue samples with high resolutions of 1-15 μm. Microelectromechanical system (MEMS) mirrors are small and can perform fast optical scans; they are suitable for realizing lateral optical scans in OCT systems. In this thesis, MEMS technology is applied to enable endoscopic OCT imaging. Two generations of MEMS mirrors have been used. The MEMS mirrors are 2 mm x 2 mm and 1.7 mm x 1.55 mm respectively in size. Four generations of MEMS-OCT endoscopic probes have been developed; the diameters of the probes are reduced from 5 mm in the first generation down to 2.5 mm in the fourth generation. The effects of the positions of the optical components and the protective tubing on OCT imaging performance have been studied through simulation and verified experimentally. In vivo imaging experiments were done on mouse tongue, mouse ear and injected tumor; layered structures of mouse tongue and ear, and accurate shape of tumor regions were clearly detected.
Download or read book Dynamic Focus tracking MEMS Scanning Micromirror for an Endoscopic Optical Coherence Tomography Based Imaging System written by Matthew Strathman and published by . This book was released on 2014 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt: We demonstrate a 3-dimensional scanning micromirror device using micro-electromechanical systems (MEMS) technology to integrate 2-dimesional spatial scanning with dynamic focal control. The electrostatically actuated devices employ a biaxial gimbal structure, to allow 2-dimensional beam scanning, and a deformable mirror membrane, for focal tunability. The 800 micrometer diameter mirrors are designed to fit inside an imaging probe sufficiently compact for use in the working channel of a standard endoscope. Large optical scanning ranges of more than 20 degrees with low actuation voltages have been achieved with these micromirror devices. Additionally, tunable mirror curvature allows dynamic control of the focal length between infinite and 25 mm with less than 100 V. High mechanical resonant frequencies, of up to 500 Hz, allow faster repositioning of the optical beam and a higher frame rate for the imaging system. These MEMS micromirror devices are used in an optical coherence tomography (OCT) imaging system. 2-dimensional, cross-sectional and spatial, images have been obtained using spectral-domain and time-domain OCT systems.
Download or read book Compact MEMS based Adaptive Optics Optical Coherence Tomography for Clinical Use written by and published by . This book was released on 2008 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: We describe a compact MEMS-based adaptive optics (AO) optical coherence tomography system with improved AO performance and ease of clinical use. A typical AO system consists of a Shack-Hartmann wavefront sensor and a deformable mirror that measures and corrects the ocular and system aberrations. Because of the limitation on the current deformable mirror technologies, the amount of real-time ocular-aberration compensation is restricted and small in the previous AO-OCT instruments. In this instrument, we proposed to add an optical apparatus to correct the spectacle aberrations of the patients such as myopia, hyperopia and astigmatism. This eliminated the tedious process of the trial lenses in clinical imaging. Different amount of spectacle aberration compensation was achieved by motorized stages and automated with the AO computer for ease of clinical use. In addition, the compact AO-OCT was optimized to have minimum system aberrations to reduce AO registration errors and improve AO performance.
Download or read book Optical MEMS for Chemical Analysis and Biomedicine written by Hongrui Jiang and published by IET. This book was released on 2016-04-21 with total page 465 pages. Available in PDF, EPUB and Kindle. Book excerpt: Optical MEMS, or MOEMS, are MEMS (micro-electromechanical systems) merged with micro-optics. They allow sensing or manipulating optical signals on a very small size scale, using integrated mechanical, optical, and electrical systems, and encompass a wide variety of devices including optical switch, optical cross-connect, tunable VCSEL, and microbolometers, among others. They give the potential of new kinds of sensors and actuators in microsystems and hold great promise specifically in biomedical applications. This book describes the current state of Optical MEMS in chemical and biomedical analysis. With contributions from an international panel of leading experts, it brings together current trends and highlights topics representing the most exciting progress in recent years in the field. Topics covered include: manufacturing technology for MOEMS; electrowetting based microoptics; MEMS-based optical scanners and their endoscopic imaging applications; photothermal microfluidics; optofluidic imaging; tuning nanophotonic cavities with nanoelectromechanical systems; biologically inspired micro-optics for biophotonic applications; microcameras; and nanostructured aluminum oxide-based optical biosensing and imaging. Optical MEMS for Chemical Analysis and Biomedicine will be essential reading for researchers and professionals working on developing, manufacturing or applying MOEMS. It will also be invaluable to advanced graduates in the field.
Download or read book Optical MEMS written by Huikai Xie and published by MDPI. This book was released on 2019-08-06 with total page 176 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a printed edition of the Special Issue Optical MEMS that was published in Micromachines
Download or read book Dielectric Fluid Enhancement of Radio Frequency MEMS Devices and Micromachined Scanners for Optical Coherence Tomography Imaging written by Daniel Thomas McCormick and published by . This book was released on 2003 with total page 566 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Performance of a MEMS based AO OCT System Using Fourier Reconstruction written by and published by . This book was released on 2009 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt: Adaptive optics (AO) and optical coherence tomography (OCT) are powerful imaging modalities that, when combined, can provide high-resolution (3.5 [mu]m isotropic), 3-D images of the retina. The AO-OCT system at UC Davis has demonstrated the utility of this technology for microscopic, volumetric, in vivo retinal imaging. The current system uses an AOptix bimorph deformable mirror (DM) for low-order, high-stroke correction and a 140-actuator Boston Micromachines DM for high-order correction. Developments to improve performance or functionality of the instrument are on-going. Based on previous work in system characterization we have focused on improved AO control. We present preliminary results and remaining challenges for a newly implemented Fourier transform reconstructor (FTR). The previously reported error budget analysis is also reviewed and updated, with consideration of how to improve both the amount of residual error and the robustness of the system. Careful characterization of the AO system will lead to improved performance and inform the design of future systems.
Download or read book Development of Optical Coherence Tomography OCT and OCT Angiography Imaging of the Mouse Brain in Vivo with Microelectromechanical System MEMS Scanning Technologies written by 張育瑋 and published by . This book was released on 2020 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Time Domain Optical Coherence Tomography OCT for MEMS based Endoscopic Application written by Yunbo Liu and published by . This book was released on 2014 with total page 51 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book MEMS Technology for Biomedical Imaging Applications written by Qifa Zhou and published by MDPI. This book was released on 2019-10-23 with total page 218 pages. Available in PDF, EPUB and Kindle. Book excerpt: Biomedical imaging is the key technique and process to create informative images of the human body or other organic structures for clinical purposes or medical science. Micro-electro-mechanical systems (MEMS) technology has demonstrated enormous potential in biomedical imaging applications due to its outstanding advantages of, for instance, miniaturization, high speed, higher resolution, and convenience of batch fabrication. There are many advancements and breakthroughs developing in the academic community, and there are a few challenges raised accordingly upon the designs, structures, fabrication, integration, and applications of MEMS for all kinds of biomedical imaging. This Special Issue aims to collate and showcase research papers, short commutations, perspectives, and insightful review articles from esteemed colleagues that demonstrate: (1) original works on the topic of MEMS components or devices based on various kinds of mechanisms for biomedical imaging; and (2) new developments and potentials of applying MEMS technology of any kind in biomedical imaging. The objective of this special session is to provide insightful information regarding the technological advancements for the researchers in the community.
Download or read book MEMS VCSEL Swept source Optical Coherence Tomography for Multi MHz Endoscopic Structural and Angiographic Imaging written by Jason Zhang (S.M.) and published by . This book was released on 2021 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt: Swept-source optical coherence tomography (SS-OCT) enables volumetric imaging of subsurface structure, but applications requiring wide fields of view, rapid imaging, and higher resolutions have been challenging because of the need for multi-MHz A-scan rates. Until now, achieving multi-MHz A-scan rates has been limited to Fourier-domain mode-locked lasers or stretched-pulse lasers. We describe a microelectromechanical-system, vertical-cavity surface-emitting laser (MEMS-VCSEL) for SS-OCT at A-scan rates of 2.4 and 3.0 MHz using a dual-channel acquisition system. Dual-channel operation enables simultaneous acquisition of Mach-Zehnder interferometer (MZI) fringes for sweep-to-sweep calibration and resampling, overcoming inherent optical clock limitations in state-of-the-art digitizers. We demonstrate structural OCT and OCT angiography (OCTA) imaging of the swine gastrointestinal tract using a suite of endoscopic devices, including a 3.2 mm diameter micromotor catheter, a 12 mm diameter tethered capsule, and a 12 mm diameter wide-field OCTA probe. MEMS-VCSELs promise to enable ultrahigh-speed SS-OCT with a scalable, low cost, and manufacturable technology, suitable for a diverse range of imaging applications.
Download or read book MEMS Mirrors written by Huikai Xie and published by MDPI. This book was released on 2018-05-04 with total page 217 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a printed edition of the Special Issue "MEMS Mirrors" that was published in Micromachines
Download or read book Optical Coherence Tomography written by Wolfgang Drexler and published by Springer Science & Business Media. This book was released on 2008-12-10 with total page 1346 pages. Available in PDF, EPUB and Kindle. Book excerpt: Optical coherence tomography (OCT) is the optical analog of ultrasound imaging and is emerging as a powerful imaging technique that enables non-invasive, in vivo, high resolution, cross-sectional imaging in biological tissue. This book introduces OCT technology and applications not only from an optical and technological viewpoint, but also from biomedical and clinical perspectives. The chapters are written by leading research groups, in a style comprehensible to a broad audience.
Download or read book Optical Coherence Tomography and Its Non medical Applications written by Michael Wang and published by BoD – Books on Demand. This book was released on 2020-05-27 with total page 226 pages. Available in PDF, EPUB and Kindle. Book excerpt: Optical coherence tomography (OCT) is a promising non-invasive non-contact 3D imaging technique that can be used to evaluate and inspect material surfaces, multilayer polymer films, fiber coils, and coatings. OCT can be used for the examination of cultural heritage objects and 3D imaging of microstructures. With subsurface 3D fingerprint imaging capability, OCT could be a valuable tool for enhancing security in biometric applications. OCT can also be used for the evaluation of fastener flushness for improving aerodynamic performance of high-speed aircraft. More and more OCT non-medical applications are emerging. In this book, we present some recent advancements in OCT technology and non-medical applications.
Download or read book Design and Fabrication of a MEMS Scanner for OCT Imaging Endo microscopic Probe written by Quentin Tanguy and published by . This book was released on 2018 with total page 201 pages. Available in PDF, EPUB and Kindle. Book excerpt: The work presented in this manuscript consists in the conception of an electro-thermo-mechanical optical micro-scanner. In a first time, a design and a model are proposed and the micro-device was fabricated, characterized and a draft of integration onto a Mirau micro-interferometer was carried out in order to build an endoscopic probe for the detection of early stage gastrointestinal cancers using an imaging technique called Optical Coherence Tomography (OCT). The very contribution of the thesis is the development and the fabrication of micro actuators driven electrothermally to control the angular position a micro mirror plate conceived in this purpose. Different architectures of micro-scanners are proposed to best comply with the specifications determined by both the optical expectations and the medical standards requirements of the final apparatus emph{in vivo}.This work, part of a project called textquote{DEMO4} was financed by the French LabEx Action funding source in cooperation between the departments AS2M and MN2S of the French research institute Femto-ST as well as the university of Florida in the USA to deliver a first demonstrator of endoscopic OCT probe.Several batches of fabrication were realized my means of techniques of ac{CMOS}-based microfabrication in exchange between Femto-ST and the university of Florida before being assembled (for lack of monolithic integration capability) onto a micro-interferometer using automated processes specifically developed in this purpose.Finally, an experimental setup is proposed to characterize in order to evaluate the performances achieved and initiate the first tests of optical imaging using the micro-system.
Download or read book Optical Coherence Tomography written by Mark E. Brezinski and published by Elsevier. This book was released on 2006-08-25 with total page 645 pages. Available in PDF, EPUB and Kindle. Book excerpt: Optical Coherence Tomography gives a broad treatment of the subject which will include 1)the optics, science, and physics needed to understand the technology 2) a description of applications with a critical look at how the technology will successfully address actual clinical need, and 3) a discussion of delivery of OCT to the patient, FDA approval and comparisons with available competing technologies. The required mathematical rigor will be present where needed but be presented in such a way that it will not prevent non-scientists and non-engineers from gaining a basic understanding of OCT and the applications as well as the issues of bringing the technology to the market. - Optical Coherence Tomography is a new medical high-resolution imaging technology which offers distinct advantages over current medical imaging technologies and is attracting a large number of researchers. - Provides non-scientists and non-engineers basic understanding of Optical Coherence Tomography applications and issues.
Download or read book Optical MEMS Nanophotonics and Their Applications written by Guangya Zhou and published by CRC Press. This book was released on 2017-12-14 with total page 548 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book covers device design fundamentals and system applications in optical MEMS and nanophotonics. Expert authors showcase examples of how fusion of nanoelectromechanical (NEMS) with nanophotonic elements is creating powerful new photonic devices and systems including MEMS micromirrors, MEMS tunable filters, MEMS-based adjustable lenses and apertures, NEMS-driven variable silicon nanowire waveguide couplers, and NEMS tunable photonic crystal nanocavities. The book also addresses system applications in laser scanning displays, endoscopic systems, space telescopes, optical telecommunication systems, and biomedical implantable systems. Presents efforts to scale down mechanical and photonic elements into the nano regime for enhanced performance, faster operational speed, greater bandwidth, and higher level of integration. Showcases the integration of MEMS and optical/photonic devices into real commercial products. Addresses applications in optical telecommunication, sensing, imaging, and biomedical systems. Prof. Vincent C. Lee is Associate Professor in the Department of Electrical and Computer Engineering, National University of Singapore. Prof. Guangya Zhou is Associate Professor in the Department of Mechanical Engineering at National University of Singapore.
