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We study the way Lyot coronagraphs with unapodized entrance pupils respond to small, low order phase aberrations. This study is applicable to ground-based adaptive optics coronagraphs operating at 90% and higher Strehl ratios, as well as to…

Photoacoustic (PA) computed tomography (PACT) shows great potentials in various preclinical and clinical applications. A great number of measurements are the premise that obtains a high-quality image, which implies a low imaging rate or a…

Computer Vision and Pattern Recognition · Computer Science 2021-06-01 Hengrong Lan , Juze Zhang , Changchun Yang , Fei Gao

The new frontier in the quest for the highest contrast levels in the focal plane of a coronagraph is now the correction of the large diffractive artifacts effects introduced at the science camera by apertures of increasing complexity. The…

Instrumentation and Methods for Astrophysics · Physics 2016-01-18 Johan Mazoyer , Laurent Pueyo , Colin Norman , Mamadou N'Diaye , Roeland P. van der Marel , Rémi Soummer

Panoramic Annular Lens (PAL) composed of few lenses has great potential in panoramic surrounding sensing tasks for mobile and wearable devices because of its tiny size and large Field of View (FoV). However, the image quality of tiny-volume…

Image and Video Processing · Electrical Eng. & Systems 2023-01-02 Qi Jiang , Hao Shi , Lei Sun , Shaohua Gao , Kailun Yang , Kaiwei Wang

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

We review some of the latest approaches to analysing cardiac electrophysiology data using machine learning and predictive modelling. Cardiac arrhythmias, particularly atrial fibrillation, are a major global healthcare challenge. Treatment…

An alternative, new laser link acquisition scheme for the triangular constellation of spacecraft (SCs) in deep space in the detection of gravitational waves is considered. In place of a wide field CCD camera in the initial stage of laser…

Instrumentation and Methods for Astrophysics · Physics 2025-09-01 Jinke Yang , Yong Xie , Yidi Fan , Pengcheng Wang , Xindong Liang , Haojie Li , Xue Wang , Zhao Cui , Jianjun Jia , Yucheng Tang , Yun Kau Lau

While drastic improvements in CT technology have occurred in the past 25 years, spatial resolution is one area where progress has been limited until recently. New photon counting CT systems, are capable of much better spatial resolution…

Automated cardiac image interpretation has the potential to transform clinical practice in multiple ways including enabling low-cost serial assessment of cardiac function in the primary care and rural setting. We hypothesized that advances…

The search for life via characterization of earth-like planets in the habitable zone is one of the key scientific objectives in Astronomy. We describe a new phase-occulting (PO) interferometric nulling coronagraphy (NC) approach. The PO-NC…

Instrumentation and Methods for Astrophysics · Physics 2015-04-23 Richard G. Lyon , Brian A. Hicks , Mark Clampin , Peter Petrone

As adaptive optics technology continues to improve, the stellar coronagraph will play an ever increasing role in ground-based high-contrast imaging observations. Though several different image masks exist for the most common type of…

Astrophysics · Physics 2009-11-13 Justin Crepp , Andrew Vanden Heuvel , Jian Ge

The current generation of ground-based coronagraphic instruments uses deformable mirrors to correct for phase errors and to improve contrast levels at small angular separations. Improving these techniques, several space and ground based…

Instrumentation and Methods for Astrophysics · Physics 2017-10-12 Johan Mazoyer , Laurent Pueyo

We present the laboratory verification of a method for re- moving the effects of frozen-flow atmospheric turbulence using a Linear Quadratic Gaussian (LQG) controller, also known as a Kalman Filter. This method, which we term "Predictive…

Instrumentation and Methods for Astrophysics · Physics 2015-04-16 Alexander Rudy , Lisa Poyneer , Srikar Srinath , S. Mark Ammons , Donald Gavel

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

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

The WFIRST-AFTA 2.4 m telescope will provide in the next decade the opportunity to host a coronagraph for the imaging and spectroscopy of planets and disks. The telescope, however, is not ideal, given its obscured aperture. Only recently…

Instrumentation and Methods for Astrophysics · Physics 2015-09-18 John Krist , Bijan Nemati , Bertrand Mennesson

A high contrast coronagraph is expected to provide one of the promising ways to directly observe extra-solar planets. We present the newest results of our laboratory experiment investigating "rigid" coronagraph with a binary shaped…

Instrumentation and Methods for Astrophysics · Physics 2011-08-17 K. Enya , L. Abe , S. Tanaka , T. Nakagawa , K. Haze , T. Sato , T. Wakayama

Focused transmits are the most commonly used transmit strategy for echocardiograms, but suffer from relatively low frame rates, and in 3D, even lower volume rates. Fast imaging based on unfocused transmits has disadvantages such as motion…

Signal Processing · Electrical Eng. & Systems 2026-05-14 Wessel L. van Nierop , Oisín Nolan , Tristan S. W. Stevens , Ruud J. G. van Sloun

For the technology development of the mission EXCEDE (EXoplanetary Circumstellar Environments and Disk Explorer) - a 0.7 m telescope equipped with a Phase-Induced Amplitude Apodization Coronagraph (PIAA-C) and a 2000-element MEMS deformable…

Instrumentation and Methods for Astrophysics · Physics 2015-06-22 Julien Lozi , Ruslan Belikov , Sandrine J. Thomas , Eugene Pluzhnik , Eduardo Bendek , Olivier Guyon , Glenn Schneider

We performed an experimental verification of a coronagraph. As a result, we confirmed that, at the focal region where the planetary point spread function exists, the coronagraph system mitigates the raw contrast of a star-planet system by…

Earth and Planetary Astrophysics · Physics 2023-07-12 Satoshi Itoh , Taro Matsuo , Shunsuke Ota , Kensuke Hara , Yuji Ikeda , Reiki Kojima , Toru Yamada , Takahiro Sumi
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