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Related papers: Ultrasound Autofocusing: Common Midpoint Phase Err…

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Transcranial ultrasound (TUS) has emerged as a promising tool in clinical and research settings due to its potential to modulate neuronal activity, open the blood-brain barrier, facilitate targeted drug delivery via nanoparticles, and…

Medical Physics · Physics 2024-10-29 Kasra Naftchi-Ardebili , Karanpartap Singh , Gerald R. Popelka , Kim Butts Pauly

We investigate the focal plane wavefront sensing technique, known as Phase Diversity, at the scientific focal plane of a segmented mirror telescope with an adaptive optics (AO) system. We specifically consider an optical system imaging a…

Instrumentation and Methods for Astrophysics · Physics 2021-05-03 Masen Lamb , Carlos Correia , Suresh Sivanandam , Robin Swanson , Polina Zavyalova

We report the characterization of an achromatic focusing metasurface at oblique incident angles. We show that in addition to the inherent off-axis aberrations that occurs due to the hyperbolic phase profile of the metasurface, the focusing…

We present a promising approach to the extremely fast sensing and correction of small wavefront errors in adaptive optics systems. As our algorithm's computational complexity is roughly proportional to the number of actuators, it is…

Instrumentation and Methods for Astrophysics · Physics 2016-11-26 Christoph U. Keller , Visa Korkiakoski , Niek Doelman , Rufus Fraanje , Raluca Andrei , Michel Verhaegen

Medical ultrasound (US) is a widespread imaging modality owing its popularity to cost efficiency, portability, speed, and lack of harmful ionizing radiation. In this paper, we demonstrate that replacing the traditional ultrasound processing…

Computer Vision and Pattern Recognition · Computer Science 2020-04-07 Sanketh Vedula , Ortal Senouf , Grigoriy Zurakhov , Alex Bronstein , Oleg Michailovich , Michael Zibulevsky

Dispersion decomposes compound light into monochromatic components at different spatial locations, which needs to be eliminated in imaging but utilized in spectral detection. Metasurfaces provide a unique path to modulate the dispersion…

Optics · Physics 2021-12-30 Yueqiang Hu , Yuting Jiang , Yi Zhang , Jiajie Lai , Peng He , Xiangnian Ou , Ling Li , Huigao Duan

Phase diversity is a widefield aberration correction method that uses multiple images to estimate the phase aberration at the pupil plane of an imaging system by solving an optimization problem. This estimated aberration can then be used to…

Image and Video Processing · Electrical Eng. & Systems 2023-08-03 Nikolaj Reiser , Min Guo , Hari Shroff , Patrick J. La Riviere

Fluorescence Correlation Spectroscopy (FCS) yields measurement parameters (number of molecules, diffusion time) that characterize the concentration and kinetics of fluorescent molecules within a supposedly known observation volume. Absolute…

Biological Physics · Physics 2011-12-23 Charles Edouard Leroux , Irène Wang , Jacques Derouard , Antoine Delon

Light scattering in inhomogeneous media induces wavefront distortions which pose an inherent limitation in many optical applications. Examples range from microscopy and nanosurgery to astronomy. In recent years, ongoing efforts have made…

Optics · Physics 2015-05-20 Ori Katz , Yaron Bromberg , Eran Small , Yaron Silberberg

Sonography techniques use multiple transducer elements for tissue visualization. Signals detected at each element are sampled prior to digital beamforming. The sampling rates required to perform high resolution digital beamforming are…

Information Theory · Computer Science 2013-07-25 Tanya Chernyakova , Yonina C. Eldar

We propose a focusing method of intense midair ultrasound out of ultrasonic emission from a single flexurally vibrating square plate partially covered with a purposely designed amplitude mask. Many applications relying on nonlinear acoustic…

Applied Physics · Physics 2024-06-04 Keisuke Hasegawa , Masaya Fujimori , Masaya Takasaki

The aberrations induced by the sample and/or by the sample holder limit the resolution of optical microscopes. Wavefront correction can be achieved using a deformable mirror with wavefront sensorless optimization algorithms but, despite the…

Multi-modal medical image fusion is essential for the precise clinical diagnosis and surgical navigation since it can merge the complementary information in multi-modalities into a single image. The quality of the fused image depends on the…

Computer Vision and Pattern Recognition · Computer Science 2023-10-25 Xianming Gu , Lihui Wang , Zeyu Deng , Ying Cao , Xingyu Huang , Yue-min Zhu

Ultrasound images vary widely across scanners, operators, and anatomical targets, which often causes models trained in one setting to generalize poorly to new hospitals and clinical conditions. The Foundation Model Challenge for Ultrasound…

Computer Vision and Pattern Recognition · Computer Science 2026-03-23 Ufaq Khan , L. D. M. S. Sai Teja , Ayuba Shakiru , Mai A. Shaaban , Yutong Xie , Muhammad Bilal , Muhammad Haris Khan

This manual is intended to help ALMA and other interferometer users improve images by recognising limitations and how to overcome them and deciding when and how to use self-calibration. The images provided by the ALMA Science Archive are…

Instrumentation and Methods for Astrophysics · Physics 2022-07-13 A. M. S. Richards , E. Moravec , S. Etoka , E. B. Fomalont , A. F. Pérez-Sánchez , M. C. Toribio , R. A. Laing

Delay-and-sum (DAS) algorithms are widely used for beamforming in linear array photoacoustic imaging systems and are characterized by fast execution. However, these algorithms suffer from various drawbacks like low resolution, low contrast,…

Medical Physics · Physics 2021-07-29 Souradip Paul , Subhamoy Mandal , Mayanglambam Suheshkumar Singh

Optical resolution photoacoustic microscopy (OR-PAM) leverages optical focusing and acoustic detection for microscopic optical absorption imaging. Intrinsically it owns high optical lateral resolution and poor acoustic axial resolution.…

Signal Processing · Electrical Eng. & Systems 2023-09-19 Yu-Hsiang Yu , Meng-Lin Li

We present a pressure sensor based on a Michelson interferometer, for use in photoacoustic tomography. Quadrature phase detection is employed allowing measurement at any point on the mirror surface without having to retune the…

Optics · Physics 2013-07-31 Rory W. Speirs , Alexis I. Bishop

Acoustic holographic lenses, also known as acoustic holograms, can change the phase of a transmitted wavefront in order to shape and construct complex ultrasound pressure fields, often for focusing the acoustic energy on a target region.…

Spatiotemporal magnetic field variations from B0-inhomogeneity and diffusion-encoding-induced eddy-currents can be detrimental to rapid image-encoding schemes such as spiral, EPI and 3D-cones, resulting in undesirable image artifacts. In…

Medical Physics · Physics 2024-11-25 Mengze Gao , Zachary Shah , Xiaozhi Cao , Nan Wang , Daniel Abraham , Kawin Setsompop
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