Download or read book Developing Wavefront Shaping Techniques for Focusing Through Highly Dynamic Scattering Media written by Ashton S. Hemphill and published by . This book was released on 2018 with total page 78 pages. Available in PDF, EPUB and Kindle. Book excerpt: One of the prime limiting factors of optical imaging in biological applications is the diffusion of light by tissue, which prevents focusing at depths greater than the optical diffusion limit of ~1 mm in soft tissue. This greatly restricts the utility of optical diagnostic and therapeutic techniques, such as optogenetics, microsurgery, optical tweezing, and phototherapy of deep tissue, which require focused light in order to function. Wavefront shaping extends the depth at which optical focusing may be achieved by compensating for phase distortions induced by scattering, allowing for focusing through constructive interference. However, due to physiological motion, scattering of light in tissue is deterministic only within a brief speckle correlation time. In in vivo soft tissue, this speckle correlation is on the order of milliseconds. Because wavefront shaping relies on deterministic scattering in order to compensate for the resulting phase distortion, the wavefront must be optimized within this brief period. This presents a challenge as the speed of digital wavefront shaping has typically been limited by the relatively long time required to measure and display the optimal phase pattern due to the low speed of cameras, data transfer and processing, and spatial light modulators. In order to overcome these restrictions, wavefront shaping techniques which minimize the time required in measurement and display are therefore vital. In this dissertation, I will describe our efforts to improve the speed of wavefront shaping without sacrificing the performance of the systems. To this end, we have successfully developed several systems which are capable of full-phase wavefront shaping with latencies of 9 ms or less. In addition, we report an all-digital alignment compensation protocol, which may be used to obtain optimal alignment in digital optical phase conjugation systems, a key component when acquiring the best possible focusing performance.
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 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 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 Light Focusing Through Scattering Media by Particle Swarm Optimization Supported by the National Natural Science Foundation of China Under Grant Nos 61178015 11304104 and 61575070 written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract : We demonstrate light focusing through scattering media by introducing particle swarm optimization for modulating the phase wavefront. Light refocusing is simulated numerically based on the angular spectrum method and the circular Gaussian distribution model of the scattering media. Experimentally, a spatial light modulator is used to control the phase of incident light, so as to make the scattered light converge to a focus. The influence of divided segments of input light and the effect of the number of iterations on light intensity enhancement are investigated. Simulation results are found to be in good agreement with the theoretical analysis for light refocusing.
Download or read book Adaptive Optics for Biological Imaging written by Joel A Kubby and published by CRC Press. This book was released on 2013-04-26 with total page 390 pages. Available in PDF, EPUB and Kindle. Book excerpt: Adaptive Optics for Biological Imaging brings together groundbreaking research on the use of adaptive optics for biological imaging. The book builds on prior work in astronomy and vision science. Featuring contributions by leaders in this emerging field, it takes an interdisciplinary approach that makes the subject accessible to nonspecialists who want to use adaptive optics techniques in their own work in biology and bioengineering. Organized into three parts, the book covers principles, methods, and applications of adaptive optics for biological imaging, providing the reader with the following benefits: Gives a general overview of applied optics, including definitions and vocabulary, to lay a foundation for clearer communication across disciplines Explains what kinds of optical aberrations arise in imaging through various biological tissues, and what technology can be used to correct for these aberrations Explores research done with a variety of biological samples and imaging instruments, including wide-field, confocal, and two-photon microscopes Discusses both indirect wavefront sensing, which uses an iterative approach, and direct wavefront sensing, which uses a parallel approach Since the sample is an integral part of the optical system in biological imaging, the field will benefit from participation by biologists and biomedical researchers with expertise in applied optics. This book helps lower the barriers to entry for these researchers. It also guides readers in selecting the approach that works best for their own applications.
Download or read book Continuous Wave Optical Techniques for Imaging Through Scattering Media written by Stephen P. Morgan and published by . This book was released on 1996 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Diagnostic Ultrasound Imaging Inside Out written by Thomas L. Szabo and published by Academic Press. This book was released on 2013-12-05 with total page 829 pages. Available in PDF, EPUB and Kindle. Book excerpt: Diagnostic Ultrasound Imaging provides a unified description of the physical principles of ultrasound imaging, signal processing, systems and measurements. This comprehensive reference is a core resource for both graduate students and engineers in medical ultrasound research and design. With continuing rapid technological development of ultrasound in medical diagnosis, it is a critical subject for biomedical engineers, clinical and healthcare engineers and practitioners, medical physicists, and related professionals in the fields of signal and image processing. The book contains 17 new and updated chapters covering the fundamentals and latest advances in the area, and includes four appendices, 450 figures (60 available in color on the companion website), and almost 1,500 references. In addition to the continual influx of readers entering the field of ultrasound worldwide who need the broad grounding in the core technologies of ultrasound, this book provides those already working in these areas with clear and comprehensive expositions of these key new topics as well as introductions to state-of-the-art innovations in this field. - Enables practicing engineers, students and clinical professionals to understand the essential physics and signal processing techniques behind modern imaging systems as well as introducing the latest developments that will shape medical ultrasound in the future - Suitable for both newcomers and experienced readers, the practical, progressively organized applied approach is supported by hands-on MATLAB® code and worked examples that enable readers to understand the principles underlying diagnostic and therapeutic ultrasound - Covers the new important developments in the use of medical ultrasound: elastography and high-intensity therapeutic ultrasound. Many new developments are comprehensively reviewed and explained, including aberration correction, acoustic measurements, acoustic radiation force imaging, alternate imaging architectures, bioeffects: diagnostic to therapeutic, Fourier transform imaging, multimode imaging, plane wave compounding, research platforms, synthetic aperture, vector Doppler, transient shear wave elastography, ultrafast imaging and Doppler, functional ultrasound and viscoelastic models
Download or read book Dynamic Wavefront Shaping with High quality factor Resonant Metasurfaces written by Elissa Ann Klopfer and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Wavefront shaping and control is essential for advancing optical technologies spanning communication, computation, and sensing. Metasurfaces promise to miniaturize future optical components, by shaping light with subwavelength nanostructures that precisely control the wave's amplitude, polarization, and phase. However, most current metasurface designs are static, unable to flexibly tune their responses to environmental or operational cues once fabricated. This thesis presents the design, fabrication, and characterization of dynamic metasurfaces that efficiently modulate their behavior based on the integration of high quality factor (high-Q) resonances. Through demonstrating a variety of devices, including lenses and beam steerers, both theoretically and experimentally this work will clearly lay out high-Q wavefront shaping metasurfaces as a promising route to achieving active devices utilizing many possible modulation mechanisms to realize a variety of transfer functions and novel design schemes.
Download or read book Future directions in novel laser source development Dynamical properties and beam manipulation written by Xing Fu and published by Frontiers Media SA. This book was released on 2022-12-19 with total page 119 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 702 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Nanoscale Photonic Imaging written by Tim Salditt and published by Springer Nature. This book was released on 2020-06-09 with total page 634 pages. Available in PDF, EPUB and Kindle. Book excerpt: This open access book, edited and authored by a team of world-leading researchers, provides a broad overview of advanced photonic methods for nanoscale visualization, as well as describing a range of fascinating in-depth studies. Introductory chapters cover the most relevant physics and basic methods that young researchers need to master in order to work effectively in the field of nanoscale photonic imaging, from physical first principles, to instrumentation, to mathematical foundations of imaging and data analysis. Subsequent chapters demonstrate how these cutting edge methods are applied to a variety of systems, including complex fluids and biomolecular systems, for visualizing their structure and dynamics, in space and on timescales extending over many orders of magnitude down to the femtosecond range. Progress in nanoscale photonic imaging in Göttingen has been the sum total of more than a decade of work by a wide range of scientists and mathematicians across disciplines, working together in a vibrant collaboration of a kind rarely matched. This volume presents the highlights of their research achievements and serves as a record of the unique and remarkable constellation of contributors, as well as looking ahead at the future prospects in this field. It will serve not only as a useful reference for experienced researchers but also as a valuable point of entry for newcomers.
Download or read book Quantitative Phase Imaging of Cells and Tissues written by Gabriel Popescu and published by McGraw Hill Professional. This book was released on 2011-03-14 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cutting-edge quantitative phase imaging techniques and their applications Filled with unique, full-color images taken by advanced quantitative phase imaging (QPI), Quantitative Phase Imaging of Cells and Tissues thoroughly explores this innovative technology and its biomedical applications. An introductory background on optical imaging and traditional optical microscopy is included to illustrate concept development. The book explains how various visualization modalities can be obtained by numerical calculations. This authoritative resource reveals how to take full advantage of the unprecedented capabilities of QPI, such as rendering scattering properties of minute subcellular structures and nanoscale fluctuations in live cells. Coverage includes: Groundwork Spatiotemporal field correlations Image characteristics Light microscopy Holography Point scanning QPI methods Principles of full-field QPI Off-axis full-field methods Phase-shifting techniques Common-path methods White light techniques Fourier transform light scattering (FTLS) Current trends in QPI
Download or read book Waves and Imaging through Complex Media written by P. Sebbah and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 452 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent advances in wave propagation in random media are certainly consequences of new approaches to fundamental issues, as well as of a strong interest in potential applications. A collective effort has been made to present in this book the state of the art in fundamental concepts, as well as in biomedical imaging techniques. As an example, the recent introduction of wave chaos, and more specifically random matrix theory - an old tool from nuclear physics - to the study of multiple scattering, has pointed the way to a deeper understanding of wave coherence in complex media. At the same time, efficient new approaches for retrieving information from random media promise to allow wave imaging of small tumors in opaque tissues. Review chapters are written by experts in the field, with the aim of making the book accessible to the widest possible scientific audience: graduate students and research scientists in theoretical and applied physics, optics, acoustics, and biomedical physics.
Download or read book Photoacoustic Tomography written by Minghua Xu and published by CRC PressI Llc. This book was released on 2014-09-30 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Essentials of In Vivo Biomedical Imaging written by Simon R. Cherry and published by CRC Press. This book was released on 2016-02-17 with total page 277 pages. Available in PDF, EPUB and Kindle. Book excerpt: While there are many excellent texts focused on clinical medical imaging, there are few books that approach in vivo imaging technologies from the perspective of a scientist or physician-scientist using, or interested in using, these techniques in research. It is for these individuals that Essentials of In Vivo Biomedical Imaging is written.Featurin
