Download or read book Ultrasound encoded Optical Tomography and Time reversed Ultrasonically Encoded Optical Focusing written by Xiao Xu and published by . This book was released on 2011 with total page 89 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ultrasound modulated optical tomography is a developing hybrid imaging modality that combines high optical contrast and good ultrasonic resolution to image soft biological tissue. We developed a photorefractive crystal-based, time-resolved detection scheme with the use of a millisecond long ultrasound burst to image both the optical and mechanical properties of biological tissues, with improved detection efficiency of ultrasound-tagged photons. We also applied spectral-hole burning (SHB) aided detection in ultrasound-modulated optical tomography (UOT) to image optical heterogeneities in thick tissue-mimicking phantom samples and chicken breast tissue. The efficiency of SHB was improved by using a Tm3+: YAG crystal of higher doping concentration (2.0-atomic%) and a double-pass pumping configuration. With the improved SHB-UOT system, we imaged absorbing, scattering, and phase contrast objects that were embedded in the middle plane of a 30-mm thick phantom sample. The imaging resolution was 0.5 mm in the lateral direction, as defined by the focal width of the ultrasonic transducer, and 1.5 mm in the axial direction, as determined by the ultrasonic burst length. We also imaged two absorbing objects embedded in the middle plane of a 32-mm thick chicken breast sample. The results suggest that the improved SHB-UOT system is one step closer to a practical optical imaging application in biological and clinical studies. Light focusing plays a central role in biomedical imaging, manipulation, and therapy. In optical scattering media such as biological tissue, light propagation is randomized by multiple scattering. Beyond one transport mean free path, where photon propagation is in the diffusive regime, direct light focusing becomes infeasible. Although various methods have been developed to overcome this optical diffusion limit, all are limited by the lack of a practical internal "guide star." Here we proposed and experimentally validated a novel concept, called Time-Reversed Ultrasonically Encoded (TRUE) optical focusing, to deliver light dynamically into any predefined location inside a scattering medium. First, diffused coherent light is encoded by an ultrasonic wave focused to a predefined location; then, the encoded component of the diffused light is time-reversed and consequently converges back to the ultrasonic focus. The ultrasonic encoding noninvasively provides a virtual internal "guide star" for the time reversal. The TRUE optical focus--dynamically defined by the ultrasonic focus--is unaffected by multiple scattering of light, which is especially desirable in biological tissue where ultrasonic scattering is ~1000 times weaker than optical scattering. Various fields, such as biomedical, colloidal, atmospheric, and ocean optics, can benefit from TRUE optical focusing. Further, the concept can be generalized for non-optical waves.
Download or read book Ultrasound mediated Optical Imaging and Focusing in Scattering Media written by Yuta Suzuki and published by . This book was released on 2014 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt: Because of its non-ionizing and molecular sensing nature, light has been an attractive tool in biomedicine. Scanning an optical focus allows not only high-resolution imaging but also manipulation and therapy. However, due to multiple photon scattering events, conventional optical focusing using an ordinary lens is limited to shallow depths of one transport mean free path (lt'), which corresponds to approximately 1 mm in human tissue. To overcome this limitation, ultrasonic modulation (or encoding) of diffuse light inside scattering media has enabled us to develop both deep-tissue optical imaging and focusing techniques, namely, ultrasound-modulated optical tomography (UOT) and time-reversed ultrasonically encoded (TRUE) optical focusing. While UOT measures the power of the encoded light to obtain an image, TRUE focusing generates a time-reversed (or phase-conjugated) copy of the encoded light, using a phase-conjugate mirror to focus light inside scattering media beyond 1 lt'. However, despite extensive progress in both UOT and TRUE focusing, the low signal-to-noise ratio in encoded-light detection remains a challenge to meeting both the speed and depth requirements for in vivo applications. This dissertation describes technological advancements of both UOT and TRUE focusing, in terms of their signal detection sensitivities, operational depths, and operational speeds. The first part of this dissertation describes sensitivity improvements of encoded-light detection in UOT, achieved by using a large area (~5 cm x 5 cm) photorefractive polymer. The photorefractive polymer allowed us to improve the detection etendue by more than 10 times that of previous detection schemes. It has enabled us to resolve absorbing objects embedded inside diffused media thicker than 80 lt', using moderate light power and short ultrasound pulses. The second part of this dissertation describes energy enhancement and fluorescent excitation using TRUE focusing in turbid media, using photorefractive materials as the phase-conjugate mirrors. By using a large-area photorefractive polymer as the phase-conjugate mirror, we boosted the focused optical energy by ~40 times over the output of a previously used photorefractive Bi12SiO20 crystal. Furthermore, using both a photorefractive polymer and a Bi12SiO20 crystal as the phase-conjugate mirrors, we show direct visualization and dynamic control of TRUE focus, and demonstrate fluorescence imaging in a thick turbid medium. The last part of this dissertation describes improvements in the scanning speed of a TRUE focus, using digital phase-conjugate mirrors in both transmission and reflection modes. By employing a multiplex recording of ultrasonically encoded wavefronts in transmission mode, we have accelerated the generation of multiple TRUE foci, using frequency sweeping of both ultrasound and light. With this technique, we obtained a 2-D image of a fluorescent target centered inside a turbid sample having a thickness of 2.4 lt'. Also, by gradually moving the focal position in reflection mode, we show that the TRUE focal intensity is improved, and can be continuously scanned to image fluorescent targets in a shorter time.
Download or read book Wavefront Shaping for Biomedical Imaging written by Joel Kubby and published by Cambridge University Press. This book was released on 2019-06-20 with total page 591 pages. Available in PDF, EPUB and Kindle. Book excerpt: Learn about the theory, techniques and applications of wavefront shaping in biomedical imaging using this unique text. With authoritative contributions from researchers who are defining the field, cutting-edge theory is combined with real-world practical examples, experimental data and the latest research trends to provide the first book-level treatment of the subject. It is suitable for both background reading and use in a course, with coverage of essential topics such as adaptive optical microscopy, deep tissue microscopy, time reversal and optical phase conjugation, and tomography. The latest images from the forefront of biomedical imaging are included, and full-colour versions are available in the eBook version. Researchers, practitioners and graduate students in optics, biophotonics, biomedical engineering, and biology who use biomedical imaging tools and are looking to advance their knowledge of the subject will find this an indispensable resource.
Download or read book Focusing Light Inside Scattering Media with Optical Phase Conjugation written by Yan Liu (Biomedical engineer) and published by . This book was released on 2016 with total page 145 pages. Available in PDF, EPUB and Kindle. Book excerpt: In scattering media such as biological tissue, the heterogeneous refractive index distribution causes light to scatter, which makes the media look opaque and prevents us from focusing light beyond 1̃ mm deep inside the media to achieve optical imaging and manipulation. Hence, the ability to focus light deep inside scattering media is highly desired, and it could revolutionize biophotonics by enabling deep-tissue non-invasive high-resolution optical microscopy, optical tweezing, optogenetics, micro-surgery, and phototherapy. To break the optical diffusion limit and focus light deep inside scattering media, optical phase conjugation based wavefront shaping techniques, such as time-reversed ultrasonically encoded (TRUE) optical focusing, are being actively developed. In this dissertation, I will describe our efforts to improve the performance (speed, focusing quality and focusing depth) of optical phase conjugation for future in vivo applications. Remarkably, we have focused light through tissue-mimicking phantoms up to 96 mm thick, and through ex vivo chicken breast tissue up to 25 mm thick.
Download or read book Coded Optical Imaging written by Jinyang Liang and published by Springer Nature. This book was released on with total page 697 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Biomedical Photoacoustics written by Wenfeng Xia and published by Springer Nature. This book was released on with total page 608 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Crystal Optics Properties and Applications written by Ashim Kumar Bain and published by John Wiley & Sons. This book was released on 2019-05-14 with total page 648 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reviews the properties and applications of photo-elastic, acousto-optic, magneto-optic, electro-optic, and photorefractive materials This book deals with the basic physical properties and applications of photo-elastic, acousto-optic, magneto-optic, electro-optic, and photorefractive materials. It also provides up-to-date information on the design and applications of various optoelectronic devices based on these materials. The first chapter of Crystal Optics: Properties and Applications covers the basic concepts of crystal optics, such as index ellipsoid or optical indicatrix, crystal symmetry, wave surface, birefringence, and the polarization of light. Chapter 2 reviews the physical phenomena of crystal optics in isotropic and crystalline materials. It describes in detail research information on modern photoelastic materials and reviews the up-to-date photoelastic device applications. Chapter 3 develops the underlying theory of acousto-optics from first principles, formulating results suitable for subsequent calculations and design. The fourth chapter describes the basic principles of magneto-optic effects and mode of interaction with magnetic materials. The fifth chapter provides an understanding of the physical phenomenon of the linear and quadratic electro-optic effects in isotropic and crystalline materials. The last chapter collects many of the most important recent developments in photorefractive effects and materials, and pays special attention to recent scientific findings and advances on photorefractive materials and devices. -Features up to date information on the design and applications of various optoelectronic devices -Looks at the basic concepts of crystal optics, including the polarization of light, effects of reflection and transmission of polarization and light polarizing devices, and more -Pays special attention to design procedures for the entire range of acousto-optic devices and various applications of these devices -Provides research information on modern magneto-optic materials and reviews the up-to-date magneto-optic device applications?up to terahertz (THz) regime Crystal Optics: Properties and Applications is an excellent book for the scientific community working in the field, including researchers, lecturers, and advanced students.
Download or read book Issues in Biomedical Engineering Research and Application 2013 Edition written by and published by ScholarlyEditions. This book was released on 2013-05-01 with total page 1153 pages. Available in PDF, EPUB and Kindle. Book excerpt: Issues in Biomedical Engineering Research and Application: 2013 Edition is a ScholarlyEditions™ book that delivers timely, authoritative, and comprehensive information about Reproductive Biomedicine. The editors have built Issues in Biomedical Engineering Research and Application: 2013 Edition on the vast information databases of ScholarlyNews.™ You can expect the information about Reproductive Biomedicine in this book to be deeper than what you can access anywhere else, as well as consistently reliable, authoritative, informed, and relevant. The content of Issues in Biomedical Engineering Research and Application: 2013 Edition has been produced by the world’s leading scientists, engineers, analysts, research institutions, and companies. All of the content is from peer-reviewed sources, and all of it is written, assembled, and edited by the editors at ScholarlyEditions™ and available exclusively from us. You now have a source you can cite with authority, confidence, and credibility. More information is available at http://www.ScholarlyEditions.com/.
Download or read book Cutting edge Technologies in Biological Sensing and Analysis written by Anh Hung Nguyen and published by CRC Press. This book was released on 2024-02-06 with total page 346 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advanced technologies have been transforming the ways we carry out biological studies as well as deliver healthcare. While micro- and nano-fabrication have provided miniaturized sensors and systems with better sensitivity and selectivity,; innovations in flexible electronics, biomaterials and telecommunications have helped in enabling novel biomedical devices, reducing cost, bringing convenience and establishing mobile-health (m-Health), and personalized- and tele-medicine. Further, the recent rise of the internet of things (IoTs) and machine learning-based approaches has paved the avenue for those biomedical systems to become popular and widely accepted by our society. In this context, we edit this book aiming to cover a broad field of novel technologies used in biological assessment and analysis for humans, animal models and in vitro platforms, in both health monitoring and biological studies. Technical topics discussed in the book include: Biosensing systems and biomedical techniques Imaging techniques and systems Biosignal analysis Animal models used in biological research
Download or read book Neural Engineering written by Bin He and published by Springer Nature. This book was released on 2020-09-21 with total page 707 pages. Available in PDF, EPUB and Kindle. Book excerpt: This third edition overviews the essential contemporary topics of neuroengineering, from basic principles to the state-of-the-art, and is written by leading scholars in the field. The book covers neural bioelectrical measurements and sensors, EEG signal processing, brain-computer interfaces, implantable and transcranial neuromodulation, peripheral neural interfacing, neuroimaging, neural modelling, neural circuits and system identification, retinal bioengineering and prosthetics, and neural tissue engineering. Each chapter is followed by homework questions intended for classroom use. This is an ideal textbook for students at the graduate and advanced undergraduate level as well as academics, biomedical engineers, neuroscientists, neurophysiologists, and industry professionals seeking to learn the latest developments in this emerging field. Advance Praise for Neural Engineering, 3rd Edition: “A comprehensive and timely contribution to the ever growing field of neural engineering. Bin He’s edited volume provides chapters that cover both the fundamentals and state-of-the-art developments by the world’s leading neural engineers." Dr. Paul Sajda, Department of Biomedical Engineering, Electrical Engineering and Radiology, Columbia University “Neural Engineering, edited by Prof. He, is an outstanding book for students entering into this fast evolving field as well as experienced researchers. Its didactic and comprehensive style, with each chapter authored by leading scientific authorities, provides the ultimate reference for the field.” Dr. Dario Farina, Department of Bioengineering, Imperial College London, London, UK "Neural Engineering has come of age. Major advances have made possible prosthesis for the blind, mind control for quadraplegics and direct intervention to control seizures in epilepsy patients. Neural Engineering brings together reviews by leading researchers in this flourishing field. Dr. Terrence Sejnowski, Salk Institute for Biolgical Studies and UC San Diego
Download or read book Handbook of Neurophotonics written by Francesco S. Pavone and published by CRC Press. This book was released on 2020-05-10 with total page 439 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Handbook of Neurophotonics provides a dedicated overview of neurophotonics, covering the use of advanced optical technologies to record, stimulate, and control the activity of the brain, yielding new insight and advantages over conventional tools due to the adaptability and non-invasive nature of light. Including 32 colour figures, this book addresses functional studies of neurovascular signaling, metabolism, electrical excitation, and hemodynamics, as well as clinical applications for imaging and manipulating brain structure and function. The unifying theme throughout is not only to highlight the technology, but to show how these novel methods are becoming critical to breakthroughs that will lead to advances in our ability to manage and treat human diseases of the brain. Key Features: Provides the first dedicated book on state-of-the-art optical techniques for sensing and imaging across at the cellular, molecular, network, and whole brain levels. Highlights how the methods are used for measurement, control, and tracking of molecular events in live neuronal cells, both in basic research and clinical practice. Covers the entire spectrum of approaches, from optogenetics to functional methods, photostimulation, optical dissection, multiscale imaging, microscopy, and structural imaging. Includes chapters that show use of voltage-sensitive dye imaging, hemodynamic imaging, multiphoton imaging, temporal multiplexing, multiplane microscopy, optoacoustic imaging, near-infrared spectroscopy, and miniature neuroimaging devices to track cortical brain activity.
Download or read book Biomedical Photonics Handbook 3 Volume Set written by Tuan Vo-Dinh and published by CRC Press. This book was released on 2014-07-29 with total page 2465 pages. Available in PDF, EPUB and Kindle. Book excerpt: This handbook presents the most recent technological advances and applications in the areas of biomedical photonics. This second edition contains introductory material and covers the state-of-the-art methods and instrumentation for biomedical photonic technologies. It integrates interdisciplinary research and development critically needed for scientists, engineers, manufacturers, teachers, students, and clinical providers to learn about the most recent advances and predicted trends in instrumentation and methods as well as clinical applications in important areas of biomedical photonics. Extensive references are provided to enhance further study.
Download or read book Novel Nonlinear Optics and Quantum Optics Approaches for Ultrasound modulated Optical Tomography in Soft Biological Tissue written by Huiliang Zhang and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Optical imaging of soft biological tissue is highly desirable since it is nonionizing and provides sensitive contrast information which enables the detection of physiological functions and abnormalities, including potentially early cancer detection. However, due to the diffusive nature of light in soft biological tissue, it is difficult to achieve simultaneously good spatial resolution and good imaging depth with pure optical imaging modalities. This work focuses on the ultrasound-modulated optical tomography (UOT): a hybrid technique which combines the advantages of ultrasonic resolution and optical contrast. In this technique, focused ultrasound and optical radiation of high temporal coherence are simultaneously applied to soft biological tissue. The intensity of the sideband, or ultrasound "tagged" photons depends on the optical absorption in the region of interest where the ultrasound is focused. Demodulation of the optical speckle pattern yields the intensity of tagged photons for each location of the ultrasonic focal spot. Thus UOT yields an image with spatial resolution of the focused ultrasound -- typically submillimeter -- whose contrast is related to local optical absorption and the diffusive properties of light in the organ. Thus it extends all the advantages of optical imaging deep into highly scattering tissue. However lack of efficient tagged light detection techniques has so far prevented ultrasound-modulated optical tomography from achieving maturity. The signal-to-noise ratio (SNR) and imaging speed are two of the most important figures of merit and need further improvement for UOT to become widely applicable. In the first part of this work, nonlinear optics detection methods have been implemented to demodulate the "tagged" photons. The most common of these is photorefractive (PR) two wave mixing (TWM) interferometry, which is a time-domain filtering technique. When used for UOT, it is found that this approach extracts not only optical properties but also mechanical properties for the area of interest. To improve on TWM, PR four wave mixing (FWM) experiments were performed to read out only the modulated light and at the same time strongly suppressing the "untagged" light. Spectral-hole burning (SHB) in a rare-earth-ion-doped crystal has been developed for UOT more recently. Experiments in Tm3 :Y3Al5O12 (Tm:YAG) show the outstanding features of SHB: large angle acceptance (etendue), light speckle processing in parallel (insensitive to the diffusive light nature) and real-time signal collection (immune to light speckle decorrelation). With the help of advanced laser stabilization techniques, two orders of magnitude improvement of SNR have been achieved in a persistent SHB material (Pr3 :Y2SiO5) compared to Tm:YAG. Also slow light with PSHB further reduces noise in Pr:YSO UOT that is caused by polarization leakage by performing time-domain filtering.
Download or read book Biomedical Photonics Handbook written by Tuan Vo-Dinh and published by CRC Press. This book was released on 2014-07-29 with total page 889 pages. Available in PDF, EPUB and Kindle. Book excerpt: Shaped by Quantum Theory, Technology, and the Genomics RevolutionThe integration of photonics, electronics, biomaterials, and nanotechnology holds great promise for the future of medicine. This topic has recently experienced an explosive growth due to the noninvasive or minimally invasive nature and the cost-effectiveness of photonic modalities in
Download or read book Biomedical Photonics Handbook Second Edition written by Tuan Vo-Dinh and published by CRC Press. This book was released on 2014-07-29 with total page 894 pages. Available in PDF, EPUB and Kindle. Book excerpt: Shaped by Quantum Theory, Technology, and the Genomics Revolution The integration of photonics, electronics, biomaterials, and nanotechnology holds great promise for the future of medicine. This topic has recently experienced an explosive growth due to the noninvasive or minimally invasive nature and the cost-effectiveness of photonic modalities in medical diagnostics and therapy. The second edition of the Biomedical Photonics Handbook presents fundamental developments as well as important applications of biomedical photonics of interest to scientists, engineers, manufacturers, teachers, students, and clinical providers. The second volume, Biomedical Diagnostics, focuses on biomedical diagnostic technologies and their applications from the bench to the bedside. Represents the Collective Work of over 150 Scientists, Engineers, and Clinicians Designed to display the most recent advances in instrumentation and methods, as well as clinical applications in important areas of biomedical photonics to a broad audience, this three-volume handbook provides an inclusive forum that serves as an authoritative reference source for a broad audience involved in the research, teaching, learning, and practice of medical technologies. What’s New in This Edition: A wide variety of photonic biochemical sensing technologies have already been developed for clinical monitoring of physiological parameters, such as blood pressure, blood chemistry, pH, temperature, and the presence of pathological organisms or biochemical species of clinical importance. Advanced photonic detection technologies integrating the latest knowledge of genomics, proteomics and metabolomics allow sensing of early disease state biomarkers, thus revolutionizing the medicine of the future. Nanobiotechnology has opened new possibilities for detection of biomarkers of disease, imaging single molecules and in situ diagnostics at the single cell level. In addition to these state-of-the art advancements, the second edition contains new topics and chapters including: • Fiber Optic Probe Design • Laser and Optical Radiation Safety • Photothermal Detection • Multidimensional Fluorescence Imaging • Surface Plasmon Resonance Imaging • Molecular Contrast Optical Coherence Tomography • Multiscale Photoacoustics • Polarized Light for Medical Diagnostics • Quantitative Diffuse Reflectance Imaging • Interferometric Light Scattering • Nonlinear Interferometric Vibrational Imaging • Multimodality Theranostics Nanoplatforms • Nanoscintillator-Based Therapy • SERS Molecular Sentinel Nanoprobes • Plasmonic Coupling Interference Nanoprobes Comprised of three books: Volume I: Fundamentals, Devices, and Techniques; Volume II: Biomedical Diagnostics; and Volume III: Therapeutics and Advanced Biophotonics, this second edition contains eight sections, and provides introductory material in each chapter. It also includes an overview of the topic, an extensive collection of spectroscopic data, and lists of references for further reading.
Download or read book Biomedical Optics written by Lihong V. Wang and published by John Wiley & Sons. This book was released on 2012-09-26 with total page 378 pages. Available in PDF, EPUB and Kindle. Book excerpt: This entry-level textbook, covering the area of tissue optics, is based on the lecture notes for a graduate course (Bio-optical Imaging) that has been taught six times by the authors at Texas A&M University. After the fundamentals of photon transport in biological tissues are established, various optical imaging techniques for biological tissues are covered. The imaging modalities include ballistic imaging, quasi-ballistic imaging (optical coherence tomography), diffusion imaging, and ultrasound-aided hybrid imaging. The basic physics and engineering of each imaging technique are emphasized. A solutions manual is available for instructors; to obtain a copy please email the editorial department at [email protected].
Download or read book El Tirano de Lombardia written by and published by . This book was released on 1790* with total page 33 pages. Available in PDF, EPUB and Kindle. Book excerpt:
