English
Related papers

Related papers: The vector-apodizing phase plate coronagraph: desi…

200 papers

The segmentation and analysis of coronary arteries from intravascular optical coherence tomography (IVOCT) is an important aspect of diagnosing and managing coronary artery disease. Current image processing methods are hindered by the time…

Machine Learning · Computer Science 2021-04-20 Arjun Balaji , Lachlan Kelsey , Kamran Majeed , Carl Schultz , Barry Doyle

Photoplethysmography (PPG) has become a ubiquitous physiological signal; however, current generative models still struggle to preserve realistic waveform morphology and learn a latent structure that captures cardiac and respiratory…

Signal Processing · Electrical Eng. & Systems 2026-05-25 Fatemeh Ghasemi Balouei , Nathan Willemsen , Mahesh Banavar , Bahman Moraffah

A large number of coronagraphs have been proposed to overcome the ratio that exists between the star and its planet. The planet finder of the Extremely Large Telescope, which is called EPICS, will certainly need a more efficient coronagraph…

Astrophysics · Physics 2009-11-13 P. Baudoz , R. Galicher , J. Baudrand , A. Boccaletti

The spectroscopy of faint planetary-mass companions to nearby stars is one of the main challenges that new-generation high-contrast spectro-imagers are going to face. In a previous work we presented a long slit coronagraph (LSC), for which…

Instrumentation and Methods for Astrophysics · Physics 2013-07-12 A. Vigan , M. N'Diaye , K. Dohlen

Using 2 aspheric mirrors, it is possible to apodize a telescope beam without losing light or angular resolution: the output beam is produced by ``remapping'' the entrance beam to produce the desired light intensity distribution in a new…

We present recent laboratory results demonstrating high-contrast coronagraphy for the future space-based large IR/Optical/Ultraviolet telescope recommended by the Decadal Survey. The High-contrast Imager for Complex Aperture Telescopes…

Laser Doppler holography was introduced as a full-field imaging technique to measure blood flow in the retina and choroid with an as yet unrivaled temporal resolution. We here investigate separating the different contributions to the power…

Medical Physics · Physics 2021-06-02 Léo Puyo , Michel Paques , Mathias Fink , José-Alain Sahel , Michael Atlan

The Programmable Liquid-crystal Active Coronagraphic Imager for the DAG telescope (PLACID) instrument is a novel high-contrast direct imaging facility that was recently installed on the new Turkish 4-m DAG telescope. In brief, PLACID…

The Gemini Planet Imager (GPI) is a next-generation, facility instrument currently being commissioned at the Gemini South observatory. GPI combines an extreme adaptive optics system and integral field spectrograph (IFS) with an…

This study is focused on the very high dynamic imaging field, specifically the direct observation of exoplanetary systems. The coronagraph is an essential technique for suppressing the star's light, making it possible to detect an exoplanet…

Instrumentation and Methods for Astrophysics · Physics 2023-07-12 Jamal Chafi , Youssef El Azhari , Ossama Azagrouze , Abdelhadi Jabiri , Zouhair Benkhaldoun , Abdelfatah Habib , Youssef Errazzouki

Several coronagraph designs have been proposed over the last two decades to directly image exoplanets. Among these designs, the vector vortex coronagraphs provide theoretically perfect starlight cancellation along with small inner working…

Instrumentation and Methods for Astrophysics · Physics 2017-11-29 Kevin Fogarty , Laurent Pueyo , Johan Mazoyer , Mamadou N'Diaye

High-contrast imaging and spectroscopy provide unique constraints for exoplanet formation models as well as for planetary atmosphere models. Instrumentation techniques in this field have greatly improved over the last two decades, with the…

Instrumentation and Methods for Astrophysics · Physics 2017-12-20 Johan Mazoyer , Laurent Pueyo , Mamadou N'Diaye , Kevin Fogarty , Neil Zimmerman , Rémi Soummer , Stuart Shaklan , Colin Norman

Coronary heart disease is a common cause of death despite being preventable. To treat the underlying plaque deposits in the arterial walls, intravascular optical coherence tomography can be used by experts to detect and characterize the…

Computer Vision and Pattern Recognition · Computer Science 2018-08-27 Nils Gessert , Matthias Lutz , Markus Heyder , Sarah Latus , David M. Leistner , Youssef S. Abdelwahed , Alexander Schlaefer

An adaptive optics (AO) system based on stochastic parallel gradient descent (SPGD) algorithm is proposed to reduce the speckle noises in the optical system of stellar coronagraph in order to further improve the contrast. The principle of…

Instrumentation and Methods for Astrophysics · Physics 2015-05-28 Bing Dong , Deqing Ren , Xi Zhang

The Habitable Worlds Observatory (HWO) mission will require coronagraphs capable of suppressing starlight at the $\sim 10^{-10}$ contrast level to directly image exo-Earths. High contrast achromatic coronagraphic masks are the missing…

Instrumentation and Methods for Astrophysics · Physics 2026-03-25 Niyati Desai , Garreth Ruane , Daniel Shanks , Lorenzo König , Susan Redmond , Bertrand Mennesson

The realization that direct imaging of extrasolar planets could be technologically feasible within the next decade or so has inspired a great deal of recent research into high-contrast imaging. We ourselves have contributed several design…

Astrophysics · Physics 2009-11-10 N. Jeremy Kasdin , Robert J. Vanderbei , Michael G. Littman , David N. Spergel

The performance of high-contrast imaging instruments is limited by wavefront errors, in particular by non-common path aberrations (NCPAs). Focal-plane wavefront sensing (FPWFS) is appropriate to handle NCPAs because it measures the…

Instrumentation and Methods for Astrophysics · Physics 2022-12-19 M. Quesnel , G. Orban de Xivry , G. Louppe , O. Absil

The Nancy Grace Roman Space Telescope Coronagraph Instrument will be the first large scale coronagraphmission with active wavefront control to be operated in space and will demonstrate technologies essential tofuture missions to image…

Instrumentation and Methods for Astrophysics · Physics 2021-08-26 Kian Milani , Ewan S. Douglas , Jaren Ashcraft

The discovery of the exoplanet Proxima b highlights the potential for the coming generation of giant segmented mirror telescopes (GSMTs) to characterize terrestrial --- potentially habitable --- planets orbiting nearby stars with direct…

Instrumentation and Methods for Astrophysics · Physics 2017-12-21 Jared R. Males , Olivier Guyon

We present the monochromatic lab verification of the newly developed SCAR coronagraph that combines a phase plate (PP) in the pupil with a microlens-fed single-mode fiber array in the focal plane. The two SCAR designs that have been…

Instrumentation and Methods for Astrophysics · Physics 2018-03-29 S. Y. Haffert , E. H. Por , C. U. Keller , M. A. Kenworthy , D. S. Doelman , F. Snik , M. J. Escuti