English
Related papers

Related papers: Accuracy of Shack-Hartmann wavefront sensor using …

200 papers

Commonly used wavefront sensors, the Shack Hartmann wavefront sensor and the pyramid wavefront sensor, for example, have large dynamic range or high sensitivity, trading one regime for the other. A new type of wavefront sensor is being…

Instrumentation and Methods for Astrophysics · Physics 2022-08-19 Meghan Farris O'Brien , Sebastiaan Y. Haffert , Joseph D. Long , Lauren Schatz , Jared R. Males , Kyle Van Gorkom , Alex Rodack

Objective. Limited access to breast cancer diagnosis globally leads to delayed treatment. Ultrasound, an effective yet underutilized method, requires specialized training for sonographers, which hinders its widespread use. Approach. Volume…

Image and Video Processing · Electrical Eng. & Systems 2023-11-21 Donya Khaledyan , Thomas J. Marini , Avice OConnell , Steven Meng , Jonah Kan , Galen Brennan , Yu Zhao , Timothy M. Baran , Kevin J. Parker

Deep learning-based models, such as convolutional neural networks, have advanced various segments of computer vision. However, this technology is rarely applied to seismic shot gather noise localization problem. This letter presents an…

Computer Vision and Pattern Recognition · Computer Science 2020-05-08 Antonio José G. Busson , Sérgio Colcher , Ruy Luiz Milidiú , Bruno Pereira Dias , André Bulcão

Measuring the centroid of a spectral line is a common problem in astronomy. Many methods have been devised to overcome limitations due to either noise in the spectra or asymmetric profiles, the most common of which are the intensity…

Instrumentation and Methods for Astrophysics · Physics 2018-09-28 Richard Teague , Daniel Foreman-Mackey

The new class of large telescopes, as the future ELT, are designed to work with Laser Guide Star (LGS) tuned to a resonance of atmosphere sodium atoms. This wavefront sensing technique presents complex issues for an application to big…

Instrumentation and Methods for Astrophysics · Physics 2018-04-20 M. Patti , M. Lombini , L. Schreiber , G. Bregoli , C. Arcidiacono , G. Cosentino , E. Diolaiti , I. Foppiani

Wavefront sensing involves estimating the phase and intensity of light, enabling a wide range of imaging applications, from adaptive optics and astronomy to biomedical imaging. Since conventional image sensors can only measure the spatial…

Image and Video Processing · Electrical Eng. & Systems 2026-04-07 Nebiyou Yismaw , Vishwanath Saragadam , Aswin C. Sankaranarayanan , M. Salman Asif

Very high dynamical range coronagraphs targeting direct exo-planet detection (10^9 - 10^10 contrast) at small angular separation (few lambda/D units) usually require an input wavefront quality on the order of ten thousandths of wavelength…

Astrophysics · Physics 2009-11-13 J. Nishikawa , L. Abe , N. Murakami , T. Kotani

Wavefront shaping techniques allow waves to be focused on a diffraction-limited target deep inside disordered media. To identify the target position, a guidestar is required that typically emits a frequency-shifted signal. Here we present a…

Applied Physics · Physics 2025-05-13 Antton Goïcoechea , Jakob Hüpfl , Stefan Rotter , François Sarrazin , Matthieu Davy

Wavefront estimation using in-focus image data is critical to many applications. This data is invariant to a sign flip with complex conjugation of the complex amplitude in the pupil, making for a non-unique solution. Information from an…

Instrumentation and Methods for Astrophysics · Physics 2016-07-08 Alexandra Greenbaum , Anand Sivaramakrishnan

Differential wavefront sensing is an essential technique for optimising the performance of many precision interferometric experiments. Perhaps the most extensive application of this is for alignment sensing using radio-frequency beats…

Instrumentation and Detectors · Physics 2021-05-26 Daniel D. Brown , Huy Tuong Cao , Alexei Ciobanu , Peter Veitch , David Ottaway

Numerical simulation of ultrasonic wave propagation provides an efficient tool for crack identification in structures, while it requires a high resolution and expensive time calculation cost in both time integration and spatial…

Computational Engineering, Finance, and Science · Computer Science 2017-12-06 Shuaifang Zhang , Dongdong He , Dongsheng Li , Zhifeng Zhang , Yu Liu , Wei Shen

The presence of a scattering medium in the imaging path between an object and an observer is known to severely limit the visual acuity of the imaging system. We present an approach to circumvent the deleterious effects of scattering, by…

Phase imaging techniques extract the optical path-length information of a scene, whereas wavefront sensors provide the shape of an optical wavefront. Since these two applications have different technical requirements, they have developed…

Optics · Physics 2018-02-28 F. Soldevila , V. Durán , P. Clemente , J. Lancis , E. Tajahuerce

Doing quantitative computed tomography (CT) using Bremsstrahlung sources requires an estimate of the spectrum emitted by the X-ray source. One method of beam hardening correction (BHC), as described by Lifton[1], first uses transmission…

Medical Physics · Physics 2025-08-13 Nikhil Deshmukh

The Giant Magellan Telescope will use laser tomography adaptive optics to correct for atmospheric turbulence using artificial guide stars created in the sodium layer of the atmosphere (altitude ~95km). The sodium layer has appreciable…

Instrumentation and Methods for Astrophysics · Physics 2024-10-18 Josephine Munro , Sarah E. Dean , Neuton Li , Israel J. Vaughn , Andrew W. Kruse , Tony Travouillon , Dragomir N. Neshev , Robert Sharp , Andrey A. Sukhorukov

Wavefront shaping is a technique to study and control light transport inside scattering media. Wavefront shaping is considered to be applicable to any complex material, yet in most previous studies, the only sample geometries that are…

Abstract Background During percutaneous puncture robotic surgical navigation, the needle insertion point is positioned on the patient's chest and abdomen body surface. By locating any point on the soft skin tissue, it is difficult to apply…

Robotics · Computer Science 2024-06-11 Zezhao Guo , Yanzhong Guo , Zhanfang Zhao

Extreme wavefront correction is required for coronagraphs on future space telescopes to reach 1e-8 or better starlight suppression for the direct imaging and characterization of exoplanets in reflected light. Thus, a suite of wavefront…

Focusing waves inside inhomogeneous media is a fundamental problem for imaging. Spatial variations of wave velocity can strongly distort propagating wavefronts and degrade image quality. Adaptive focusing can compensate for such aberration,…

Image and Video Processing · Electrical Eng. & Systems 2020-06-15 William Lambert , Laura A. Cobus , Thomas Frappart , Mathias Fink , Alexandre Aubry

Medical image segmentation is a critical task that plays a vital role in diagnosis, treatment planning, and disease monitoring. Accurate segmentation of anatomical structures and abnormalities from medical images can aid in the early…

Computer Vision and Pattern Recognition · Computer Science 2023-09-14 Reza Azad , Amirhossein Kazerouni , Alaa Sulaiman , Afshin Bozorgpour , Ehsan Khodapanah Aghdam , Abin Jose , Dorit Merhof
‹ Prev 1 4 5 6 7 8 10 Next ›