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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

Phase aberration is an inherent side effect of ultrasound imaging due to the speed of sound inhomogeneity nature of human tissues, resulting in focusing error and reduced image contrast. This work introduces a phase aberration correction…

Signal Processing · Electrical Eng. & Systems 2023-08-29 Wei-Hsiang Shen , Yu-An Lin , Pai-Chi Li , Meng-Lin Li

Stellar coronagraph performance is highly sensitive to optical aberrations. In order to effectively suppress starlight for exoplanet imaging applications, low-order wavefront aberrations entering a coronagraph such as tip-tilt, defocus and…

Instrumentation and Methods for Astrophysics · Physics 2015-06-17 Hari Subedi , Neil T. Zimmerman , N. Jeremy Kasdin , Kathleen Cavanagh , A J Eldorado Riggs

Direct imaging of Earth-like planets from space requires dedicated observatories, combining large segmented apertures with instruments and techniques such as coronagraphs, wavefront sensors, and wavefront control in order to reach the high…

In single molecule orientation localization microscopy, valuable information about the orientation and longitudinal position of each molecule is often encoded in the shape of the point spread function (PSF). This shape, though, can be…

The estimation and compensation of quasi-static aberrations is mandatory to reach the ultimate performance of high-contrast imaging systems. COFFEE is a focal plane wave-front sensing method that consists in the extension of phase diversity…

Instrumentation and Methods for Astrophysics · Physics 2015-06-17 B. Paul , L. M. Mugnier , J. -F. Sauvage , K. Dohlen

The progression of deep learning and the widespread adoption of sensors have facilitated automatic multi-view fusion (MVF) about the cardiovascular system (CVS) signals. However, prevalent MVF model architecture often amalgamates CVS…

Machine Learning · Computer Science 2024-06-14 Qihan Hu , Daomiao Wang , Hong Wu , Jian Liu , Cuiwei Yang

The continual push to directly image exoplanets at lower masses and closer separations orbiting around bright stars remains limited by both quasi-static and residual adaptive optics (AO) aberration. In previous papers we have proposed a…

Instrumentation and Methods for Astrophysics · Physics 2020-04-29 Benjamin Gerard , Christian Marois

In an effort to transcend the limitations of differential imaging of exoplanets in the era of extremely large telescopes (ELTs), the first paper in this series established a rigorous, fully polarimetric framework for determining the science…

Instrumentation and Methods for Astrophysics · Physics 2016-02-18 Richard A. Frazin

The recent IRLOS upgrade for VLT/MUSE narrow field mode (NFM) introduced a full-pupil mode to enhance sensitivity and sky coverage. This involved replacing the 2x2 Shack-Hartmann sensor with a single lens for full-aperture photon…

Instrumentation and Methods for Astrophysics · Physics 2024-06-14 Arseniy Kuznetsov , Sylvain Oberti , Benoit Neichel , Thierry Fusco

We discuss the use of parametric phase-diverse phase retrieval as an in-situ high-fidelity wavefront measurement method to characterize and optimize the transmitted wavefront of a high-contrast coronagraphic instrument. We apply our method…

Instrumentation and Methods for Astrophysics · Physics 2019-03-06 Gregory R. Brady , Christopher Moriarty , Peter Petrone , Iva Laginja , Keira Brooks , Tom Comeau , Lucie Leboulleux , Remi Soummer

This paper introduces a two-and multi-level phase mask design for improved depth of focus. A novel technique is proposed incorporating cubic and generalized cubic wavefront coding (WFC). The obtained system is optical-electronic requiring…

Optics · Physics 2017-07-26 Vladimir Katkovnik , Nicholas Hogasten , Karen Egiazarian

Optical phase conjugation (OPC) is a nonlinear technique used for counteracting wavefront distortions, with various applications ranging from imaging to beam focusing. Here, we present the design of a diffractive wavefront processor to…

Optics · Physics 2024-06-13 Che-Yung Shen , Jingxi Li , Tianyi Gan , Mona Jarrahi , Aydogan Ozcan

Ultrasound (US) is widely used for clinical imaging applications thanks to its real-time and non-invasive nature. However, its lesion detectability is often limited in many applications due to the phase aberration artefact caused by…

Image and Video Processing · Electrical Eng. & Systems 2022-02-18 Shujaat Khan , Jaeyoung Huh , Jong Chul Ye

This paper introduces a novel wavefront sensing approach that relies on the Fourier analysis of a single conventional direct image. In the high Strehl ratio regime, the relation between the phase measured in the Fourier plane and the…

Instrumentation and Methods for Astrophysics · Physics 2015-06-15 Frantz Martinache

Quasi-static aberrations in coronagraphic systems are the ultimate limitation to the capabilities of exoplanet imagers both ground-based and space-based. These aberrations - which can be due to various causes such as optics alignment or…

Instrumentation and Methods for Astrophysics · Physics 2019-07-31 Olivier Herscovici-Schiller , Jean-François Sauvage , Laurent M. Mugnier , Kjetil Dohlen , Arthur Vigan

Ultrasound imaging often suffers from image degradation stemming from phase aberration, which represents a significant contributing factor to the overall image degradation in ultrasound imaging. Frequency-space prediction filtering or FXPF…

Image and Video Processing · Electrical Eng. & Systems 2023-08-24 Mostafa Sharifzadeh , Habib Benali , Hassan Rivaz

The family of multi-plane phase retrieval sensors, such as the curvature and nonlinear curvature wavefront sensors (WFS), contain tip/tilt information embedded in their signals. We have built a nonlinear curvature WFS to study different…

Instrumentation and Methods for Astrophysics · Physics 2026-03-12 Caleb G. Abbott , Justin R. Crepp , Brian Sands

In direct imaging of exoplanets from space, achieving the required dynamic range (i.e., planet-to-star contrast in brightness) currently relies on coronagraphic technology combined with active control of one or more deformable mirrors (DMs)…

Instrumentation and Methods for Astrophysics · Physics 2016-08-18 Richard A. Frazin

Inverse problems in imaging are typically ill-posed and are usually solved by employing regularized optimization techniques. The usage of appropriate constraints can restrict the solution space, thus making it feasible for a reconstruction…

Image and Video Processing · Electrical Eng. & Systems 2025-11-14 Jasleen Birdi , Tamal Majumder , Debanjan Halder , Muskan Kularia , Kedar Khare