English
Related papers

Related papers: A deep learning approach for focal-plane wavefront…

200 papers

Exoplanet direct imaging using adaptive optics (AO) is often limited by non-common path aberrations (NCPAs) and aberrations that are invisible to traditional pupil-plane wavefront sensors (WFSs). This can be remedied by focal-plane (FP)…

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

With the recent commissioning of ground instruments such as SPHERE or GPI and future space observatories like WFIRST-AFTA, coronagraphy should probably become the most efficient tool for identifying and characterizing extra-solar planets in…

Instrumentation and Methods for Astrophysics · Physics 2017-09-11 François Hénault , Alexis Carlotti , Christophe Vérinaud

The nonlinear curvature wavefront sensor (nlCWFS) has been shown to be a promising alternative to existing wavefront sensor designs. Theoretical studies indicate that the inherent sensitivity of this device could offer up to a factor of 10…

Instrumentation and Methods for Astrophysics · Physics 2022-09-02 Stanimir Letchev , Jonathan Crass , Justin R. Crepp , Sam Potier

While recent advances in deep learning have significantly advanced the state of the art for vessel detection in color fundus (CF) images, the success for detecting vessels in fluorescein angiography (FA) has been stymied due to the lack of…

Computer Vision and Pattern Recognition · Computer Science 2020-05-12 Li Ding , Mohammad H. Bawany , Ajay E. Kuriyan , Rajeev S. Ramchandran , Charles C. Wykoff , Gaurav Sharma

Machine learning is attracting surging interest across nearly all scientific areas by enabling the analysis of large datasets and the extraction of scientific information from incomplete data. Data-driven science is rapidly growing,…

Applied Physics · Physics 2025-03-17 Sung Yun Lee , Do Hyung Cho , Chulho Jung , Daeho Sung , Daewoong Nam , Sangsoo Kim , Changyong Song

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

Automatic heart sound abnormality detection can play a vital role in the early diagnosis of heart diseases, particularly in low-resource settings. The state-of-the-art algorithms for this task utilize a set of Finite Impulse Response (FIR)…

Computer Vision and Pattern Recognition · Computer Science 2019-04-25 Ahmed Imtiaz Humayun , Shabnam Ghaffarzadegan , Zhe Feng , Taufiq Hasan

Strong turbulence conditions create amplitude aberrations through the effects of near-field diffraction. When integrated over long optical path lengths, amplitude aberrations (seen as scintillation) can nullify local areas in the recorded…

Instrumentation and Methods for Astrophysics · Physics 2020-12-30 Justin R. Crepp , Stanimir O. Letchev , Sam J. Potier , Joshua H. Follansbee , Nicholas T. Tusay

One of the primary sources of suboptimal image quality in ultrasound imaging is phase aberration. It is caused by spatial changes in sound speed over a heterogeneous medium, which disturbs the transmitted waves and prevents coherent…

Image and Video Processing · Electrical Eng. & Systems 2024-07-03 Mostafa Sharifzadeh , Sobhan Goudarzi , An Tang , Habib Benali , Hassan Rivaz

In astronomy and microscopy, distortions in the wavefront affect the dynamic range of a high contrast imaging system. These aberrations are either imposed by a turbulent medium such as the atmosphere, by static or thermal aberrations in the…

Instrumentation and Methods for Astrophysics · Physics 2015-06-18 Benjamin Pope , Nick Cvetojevic , Anthony Cheetham , Frantz Martinache , Barnaby Norris , Peter Tuthill

Second-generation exoplanet imagers using extreme adaptive optics and coronagraphy have demonstrated their great potential for studying close circumstellar environments and for detecting new companions and helping to understand their…

Instrumentation and Methods for Astrophysics · Physics 2019-08-28 A. Vigan , M. N'Diaye , K. Dohlen , J. -F. Sauvage , J. Milli , G. Zins , C. Petit , Z. Wahhaj , F. Cantalloube , A. Caillat , A. Costille , J. Le Merrer , A. Carlotti , J. -L. Beuzit , D. Mouillet

Recent deepfake detection methods have increasingly explored frequency domain representations to reveal manipulation artifacts that are difficult to detect in the spatial domain. However, most existing approaches rely primarily on spectral…

Computer Vision and Pattern Recognition · Computer Science 2026-01-12 Zhen-Xin Lin , Shang-Kuan Chen

High contrast imaging and spectroscopy provide unique constraints for exoplanet formation models as well as for planetary atmosphere models. But this can be challenging because of the planet-to-star small angular separation and high flux…

Instrumentation and Methods for Astrophysics · Physics 2016-04-06 J. -R. Delorme , R. Galicher , P. Baudoz , G. Rousset , J. Mazoyer , O. Dupuis

Voxel-based multiple testing is widely used in neuroimaging data analysis. Traditional false discovery rate (FDR) control methods often ignore the spatial dependence among the voxel-based tests and thus suffer from substantial loss of…

Machine Learning · Statistics 2024-05-06 Taehyo Kim , Hai Shu , Qiran Jia , Mony J. de Leon

Non Common Path Aberrations (NCPA) are often considered as a critical issue in Adaptive Optics (AO) systems, since they introduce bias errors between real wavefronts propagating to the science detectors and those measured by the Wavefront…

Instrumentation and Methods for Astrophysics · Physics 2019-09-12 Francois Henault

High quality, repeatable point-spread functions are important for science cases like direct exoplanet imaging, high-precision astrometry, and high-resolution spectroscopy of exoplanets. For such demanding applications, the initial on-sky…

Instrumentation and Methods for Astrophysics · Physics 2021-07-19 Steven P. Bos , Michael Bottom , Sam Ragland , Jacques-Robert Delorme , Sylvain Cetre , Laurent Pueyo

To reach the full potential of the new generation of ground based telescopes, an extremely fine adjustment of the phase is required. Wavefront control and correction before detection has therefore become one of the cornerstones of…

Instrumentation and Methods for Astrophysics · Physics 2022-10-25 Vincent Chambouleyron , Olivier Fauvarque , Cédric Plantet , Jean-François Sauvage , Nicolas Levraud , Mahawa Cissé , Benoît Neichel , Thierry Fusco

The shape of a focus-modulated point spread function (PSF) is used as a quick visual assessment tool of aberration modes in the PSF. Further analysis in terms of shape moments can permit quantifying the modal coefficients with an accuracy…

Instrumentation and Methods for Astrophysics · Physics 2014-08-11 Hanshin Lee

Focal plane wavefront sensing is an appealing technique to cophase multiple aperture telescopes. Phase diversity, operable with any aperture configuration or source extension, generally suffers from high computing load. In this Letter, we…

Instrumentation and Methods for Astrophysics · Physics 2020-12-07 Sebastien Vievard , Aurelie Bonnefois , Frederic Cassaing , Joseph Montri , Laurent Mugnier
‹ Prev 1 3 4 5 6 7 10 Next ›