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Related papers: Diffraction Analysis of 2-D Pupil Mapping for High…

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Direct imaging and spectroscopy of Earth-like planets and young Jupiters require contrasts up to 10^6-10^10 at angular separations of a few dozen milliarcseconds. To achieve this goal, one of the most promising approaches consists of using…

Instrumentation and Methods for Astrophysics · Physics 2022-02-25 Lucie Leboulleux , Alexis Carlotti , Mamadou N'Diaye

We demonstrate that microlensing can be used for detecting planets in binary stellar systems. This is possible because in the geometry of planetary binary systems where the planet orbits one of the binary component and the other binary star…

The direct detection and characterization of exoplanets will be a major scientific driver over the next decade, involving the development of very large telescopes and requires high-contrast imaging close to the optical axis. Some complex…

Instrumentation and Methods for Astrophysics · Physics 2017-05-16 M. Beaulieu , L. Abe , P. Martinez , P. Baudoz , C. Gouvret , F. Vakili

Grazing Incidence X-ray Diffraction (GIXD) is a surface sensitive X-ray investigation technique (or geometry configuration) that can reveal the structural properties of a film deposited on a flat substrate. The term grazing indicates that…

Soft Condensed Matter · Physics 2015-12-29 Samuele Lilliu , Thomas Dane

Video-based eye tracking is a valuable technique in various research fields. Numerous open-source eye tracking algorithms have been developed in recent years, primarily designed for general application with many different camera types.…

Computer Vision and Pattern Recognition · Computer Science 2017-06-28 Terence Brouns

The aberrations in an optical microscope are commonly measured and corrected at one location in the field of view, within the so-called isoplanatic patch. Full-field correction is desirable for high-resolution imaging of large specimens.…

Optics · Physics 2021-06-04 Daniele Ancora , Tommaso Furieri , Stefano Bonora , Andrea Bassi

Fast and robust pupil detection is an essential prerequisite for video-based eye-tracking in real-world settings. Several algorithms for image-based pupil detection have been proposed, their applicability is mostly limited to laboratory…

Computer Vision and Pattern Recognition · Computer Science 2015-11-24 Wolfgang Fuhl , Thiago C. Santini , Thomas Kuebler , Enkelejda Kasneci

Phase apodization coronagraphs are implemented in a pupil plane to create a dark hole in the science camera focal plane. They are successfully created as "Apodizing Phase Plates" (APPs) using classical optical manufacturing, and as…

Instrumentation and Methods for Astrophysics · Physics 2022-05-11 Matthew A. Kenworthy , Johanan L. Codona , Frans Snik

High-contrast imaging surveys for exoplanet detection have shown giant planets at large separations to be rare. It is important to push towards detections at smaller separations, the part of the parameter space containing most planets. The…

Earth and Planetary Astrophysics · Physics 2021-03-16 M. Samland , J. Bouwman , D. W. Hogg , W. Brandner , T. Henning , M. Janson

Well over 700 exoplanets have been detected to date. Only a handful of these have been observed directly. Direct observation is extremely challenging due to the small separation and very large contrast involved. Imaging polarimetry offers a…

Instrumentation and Methods for Astrophysics · Physics 2015-06-12 M. Rodenhuis , H. Canovas , S. V. Jeffers , M. de Juan Ovelar , L. Homs , M. Min , C. U. Keller

Planetary atmospheres are inherently 3D objects that can have strong gradients in latitude, longitude, and altitude. Secondary eclipse mapping is a powerful way to map the 3D distribution of the atmosphere, but the data can have large…

Gaussian aperture pupil masks (GAPMs) can in theory achieve the contrast requisite for directly imaging an extrasolar planet. We outline the process of fabricating and testing a GAPM for use on the Penn State near-IR Imager and Spectrograph…

Astrophysics · Physics 2007-05-23 J. H. Debes , J. Ge , C. Mendelowitz , A. Watson

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

Pupil reflex to variations in illumination and associated dynamics are of importance in neurology and ophthalmology. This is typically measured using a near Infrared (IR) pupillometer to avoid Purkinje reflections that appear when strong…

Image and Video Processing · Electrical Eng. & Systems 2023-08-21 Abhijeet Phatak , Aditya Chandra Mandal , Janarthanam Jothi Balaji , Vasudevan Lakshminarayanan

Precession of a converged beam during acquisition of a 4D-STEM dataset improves strain, orientation, and phase mapping accuracy by averaging over continuous angles of illumination. Precession experiments usually rely on integrated systems,…

Instrumentation and Detectors · Physics 2025-10-20 Stephanie M. Ribet , Rohan Dhall , Colin Ophus , Karen C. Bustillo

We present an analytical description and an experimental realization of interscale mixing microscopy, a diffraction-based imaging technique that is capable of detecting wavelength/10 objects in far-field measurements with both coherent and…

WFIRST will conduct a coronagraphic program of characterizing the atmospheres of planets around bright nearby stars. When observed with the WFIRST Wide Field Camera, these stars will saturate the detector and produce very strong diffraction…

Instrumentation and Methods for Astrophysics · Physics 2018-02-08 Peter Melchior , David Spergel , Arianna Lanz

We present a MIR coronagraph to target the direct observation of extrasolar planets for SPICA, in which a coronagraph is currently regarded as an option of the focal plane instruments. The primary target of the SPICA coronagraph is the…

Earth and Planetary Astrophysics · Physics 2019-08-14 Keigo Enya

X-ray ptychography is one of the versatile techniques for nanometer resolution imaging. The magnitude of the diffraction patterns is recorded on a detector and the phase of the diffraction patterns is estimated using phase retrieval…

Image and Video Processing · Electrical Eng. & Systems 2021-05-21 Prasan Shedligeri , Florian Schiffers , Semih Barutcu , Pablo Ruiz , Aggelos K Katsaggelos , Oliver Cossairt

We propose a new approach for high-contrast imaging at the diffraction limit using segmented telescopes in a modest observation bandwidth. This concept, named "spectroscopic fourth-order coronagraphy", is based on a fourth-order coronagraph…

Instrumentation and Methods for Astrophysics · Physics 2021-03-17 Taro Matsuo , Satoshi Itoh , Yuji Ikeda