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Related papers: Segmented coronagraph design and analysis (SCDA): …

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Coronary artery stenosis is a critical health risk, and its precise identification in Coronary Angiography (CAG) can significantly aid medical practitioners in accurately evaluating the severity of a patient's condition. The complexity of…

Computer Vision and Pattern Recognition · Computer Science 2023-11-20 In Kyu Lee , Junsup Shin , Yong-Hee Lee , Jonghoe Ku , Hyun-Woo Kim

The imaging and characterization of a larger range of exoplanets, down to young Jupiters and exo-Earths will require accessing very high contrasts at small angular separations with an increased robustness to aberrations, three constraints…

The Astro2020 decadal survey recommended an infrared, optical, ultra-violet (IR/O/UV) telescope with a $\sim$6~m inscribed diameter and equipped with a coronagraph instrument to directly image exoEarths in the habitable zone of their host…

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

Direct observation of extra-solar planets (exoplanets) is essential to understand how planetary systems were born, how they evolve, and ultimately, to identify biological signatures on these planets. However, the enormous contrast in flux…

Instrumentation and Methods for Astrophysics · Physics 2012-01-11 Kanae Haze

We propose a method based on deep learning to perform cardiac segmentation on short axis MRI image stacks iteratively from the top slice (around the base) to the bottom slice (around the apex). At each iteration, a novel variant of U-net is…

Computer Vision and Pattern Recognition · Computer Science 2018-04-26 Qiao Zheng , Hervé Delingette , Nicolas Duchateau , Nicholas Ayache

X-ray polarimetry can potentially constrain the unknown geometrical shape of AGN coronae. We present simulations of the X-ray polarization signal expected from AGN coronae, assuming three different geometries, namely slab, spherical and…

High Energy Astrophysical Phenomena · Physics 2022-01-05 F. Ursini , G. Matt , S. Bianchi , A. Marinucci , M. Dovčiak , W. Zhang

The design of liquid-crystal diffractive phase plate coronagraphs for ground-based and space-based high-contrast imaging systems is limited by the trade-off between spectral bandwidth and polarization leakage. We demonstrate that by…

Instrumentation and Methods for Astrophysics · Physics 2020-03-13 David S. Doelman , Emiel H. Por , Garreth Ruane , Michael J. Escuti , Frans Snik

Lung cancer is the leading cause of cancer death worldwide. The best solution for lung cancer is to diagnose the pulmonary nodules in the early stage, which is usually accomplished with the aid of thoracic computed tomography (CT). As deep…

Image and Video Processing · Electrical Eng. & Systems 2023-03-08 Rui Xu , Zhi Liu , Yong Luo , Han Hu , Li Shen , Bo Du , Kaiming Kuang , Jiancheng Yang

The high-contrast coronagraph for direct imaging earth-like exoplanet at the visible needs a contrast of 10^(-10) at a small angular separation of 4 lambda/D or less. Here we report our recent laboratory experiment that is close to the…

Instrumentation and Methods for Astrophysics · Physics 2014-06-12 C. C. Liu , D. Q. Ren , J. P. Dou , Y. T. Zhu , X. Zhang , G. Zhao , Zh. Wu , R. Chen

Active coronagraphy is deemed to play a key role for the next generation of high-contrast instruments, notably in order to deal with large segmented mirrors that might exhibit time-dependent pupil merit function, caused by missing or…

Instrumentation and Methods for Astrophysics · Physics 2018-08-03 Jonas Kuhn , Polychronis Patapis , Xin Lu , Marcel Arikan

With the increasing number of CT scan examinations, there is a need for automated methods such as organ segmentation, anomaly detection and report generation to assist radiologists in managing their increasing workload. Multi-label…

Computer Vision and Pattern Recognition · Computer Science 2025-08-05 Theo Di Piazza , Carole Lazarus , Olivier Nempont , Loic Boussel

The purpose of this paper is to present the results of a theoretical study pertaining to the feasibility of PIAA units using Deformable Mirrors. We begin by reviewing the general derivation of the design equations driving PIAA. We then show…

Instrumentation and Methods for Astrophysics · Physics 2011-11-23 Laurent Pueyo , N. Jeremy Kasdin , Alexis Carlotti , Robert Vanderbei

We present the SPICA Coronagraphic Instrument (SCI), which has been designed for a concentrated study of extra-solar planets (exoplanets). SPICA mission provides us with a unique opportunity to make high contrast observations because of its…

The detection and characterization of extrasolar planets with SPHERE (Spectro Polarimetric High contrast Exoplanet REsearch) is challenging and in particular relies on the ability of a coronagraph to attenuate the diffracted starlight.…

A spiral holographic aperture is used in the condensor plane of a scanning transmission electron microscope to produce a focussed electron vortex probe carrying a topological charge of either $-1,0$ or $+1$. The spiral aperture design has a…

Optics · Physics 2014-05-29 J. Verbeeck H. Tian A. Béché

We investigate the stability of a segmented deformable mirror (DM) on high-contrast testbeds and its impact on the images produced with coronagraphs. Segmented apertures are promising to obtain large primary mirrors for future missions with…

A polarization-multiplexed, dual-beam setup is proposed to expand the field of view for a swept source optical coherence tomography angiography (OCTA) system. This method used a Wollaston prism to split sample path light into two…

Medical Physics · Physics 2017-10-30 Jianlong Yang , Rahul Chandwani , Rui Zhao , Zhuo Wang , Yali Jia , David Huang , Gangjun Liu

Diagnosis of cardiovascular disease using automated methods often relies on the critical task of cardiac image segmentation. We propose a novel strategy that performs segmentation using specialist networks that focus on a single anatomy…

Image and Video Processing · Electrical Eng. & Systems 2024-02-15 Abbas Khan , Muhammad Asad , Martin Benning , Caroline Roney , Gregory Slabaugh

We present designs for fully achromatic vector Apodizing Phase Plate (vAPP) coronagraphs, that implement low polarization leakage solutions and achromatic beam-splitting, enabling observations in broadband filters. The vAPP is a pupil plane…

Instrumentation and Methods for Astrophysics · Physics 2018-11-27 Steven P. Bos , David S. Doelman , Jos de Boer , Emiel H. Por , Barnaby Norris , Michael J. Escuti , Frans Snik
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