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Direct imaging of exoplanets requires very high contrast levels, which are obtained using coronagraphs. But residual quasi-static aberrations create speckles in the focal plane downstream of the coronagraph which mask the planet. This…

Instrumentation and Methods for Astrophysics · Physics 2015-06-16 J. Mazoyer , P. Baudoz , R. Galicher , M. Mas , G. Rousset

Polarization-resolved near-infrared imaging adds a useful optical contrast mechanism to eye tracking by measuring the polarization state of light reflected by ocular tissues in addition to its intensity. In this paper we demonstrate how…

We utilize the localization analysis method to precisely determine the light beam positions with the spatial separation beyond the optical diffraction limit. By such a direct spatial measurement, the associated optical setup is built to…

Instrumentation and Detectors · Physics 2018-10-11 Hoi Chun Chiu , Zhuohui Zeng , Luwei Zhao , Teng Zhao , Shengwang Du , Xian Chen

In optical devices like diffraction gratings and Fresnel lenses, light wavefront is engineered through the structuring of device surface morphology, within thicknesses comparable to the light wavelength. Fabrication of such diffractive…

Optics · Physics 2021-07-28 S. L. Oscurato , F. Reda , M. Salvatore , F. Borbone , P. Maddalena , A. Ambrosio

The past decade has seen a significant growth in research targeted at space based observatories for imaging exo-solar planets. The challenge is in designing an imaging system for high-contrast. Even with a perfect coronagraph that modifies…

Instrumentation and Methods for Astrophysics · Physics 2011-11-23 Laurent Pueyo , Jason Kay , N. Jeremy Kasdin , Tyler Groff , Michael Mc Elwain , Amir Give'on , Ruslan Belikov

Future high-contrast imagers on ground-based extremely large telescopes will have to deal with the segmentation of the primary mirrors. Residual phase errors coming from the phase steps at the edges of the segments will have to be minimized…

Instrumentation and Methods for Astrophysics · Physics 2020-12-08 A. Vigan , M. Postnikova , A. Caillat , J. -F. Sauvage , K. Dohlen , K. El Hadi , T. Fusco , M. Lamb , M. N'Diaye

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 have upgraded IRCAL, the near-infrared science camera of the Lick Observatory adaptive optics system, to add a dual-channel imaging polarimetry mode. This mode uses an optically contacted YLF (LiYF_4) Wollaston prism to provide…

Astrophysics · Physics 2009-11-13 Marshall D. Perrin , James R. Graham , James P. Lloyd

We consider an ultra-small system of polarized bosons on an optical lattice with a ring topology interacting via long range dipole-dipole interactions. Dipoles polarized perpendicular to the plane of the ring reveal sharp transitions…

Quantum Gases · Physics 2013-05-29 Michal Maik , Pierfrancesco Buonsante , Alessandro Vezzani , Jakub Zakrzewski

Detection of a gravitational-wave stochastic background via ground or space-based gravitational-wave detectors requires the cross-correlation of the response of two or more independent detectors. The cross-correlation involves a…

General Relativity and Quantum Cosmology · Physics 2009-11-06 Lee Samuel Finn , Shane L. Larson , Joseph D. Romano

The polarimetric properties of an adjustable two plate quarter-wave system have been investigated. Multiple beam interference within single wave-plates has been taken into account. It has been shown that different adjustments are needed to…

Optics · Physics 2015-06-12 Evelina A. Bibikova , Nataliya D. Kundikova

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

Gravitational wave (GW) observations of binary black hole (BBH) coalescences provide a unique opportunity to test general relativity (GR) in the strong-field regime. To ensure the reliability of these tests, it is essential to identify and…

General Relativity and Quantum Cosmology · Physics 2026-01-06 Purnima Narayan , Nathan K. Johnson-McDaniel , Anuradha Gupta

The ability to resolve the polarization of light with on-chip devices represents an urgent problem in optoelectronics. The detectors with polarization resolution demonstrated so far mostly require multiple oriented detectors or movable…

Mesoscale and Nanoscale Physics · Physics 2022-05-19 Valentin Semkin , Dmitry Mylnikov , Elena Titova , Sergey Zhukov , Dmitry Svintsov

The observables in a strong gravitational lens are usually just the image positions and sometimes the flux ratios. We develop a new and simple algorithm which allows a set of models to be fitted exactly to the observations. Taking our cue…

Astrophysics · Physics 2008-11-26 N. W. Evans , H. J. Witt

Polarized light microscopy, as a contrast-enhancing technique for optically anisotropic materials, is a method well suited for the investigation of a wide variety of effects in solid-state physics, as for example birefringence in crystals…

Instrumentation and Detectors · Physics 2017-12-19 Matthias Lange , Stefan Guénon , Felix Lever , Reinhold Kleiner , Dieter Koelle

Weak gravitational lensing observations are a key science driver for the NASA Wide Field Infrared Survey Telescope (WFIRST). To validate the performance of the WFIRST infrared detectors, we have performed a laboratory emulation of weak…

Instrumentation and Methods for Astrophysics · Physics 2015-06-16 Suresh Seshadri , Charles Shapiro , Timothy Goodsall , Jason Fucik , Christopher M. Hirata , Jason Rhodes , Barnaby Rowe , Roger Smith

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…

Interferometry provides one of the possible routes to ultra-high angular resolution for X-ray and gamma-ray astronomy. Sub-micro-arc-second angular resolution, necessary to achieve objectives such as imaging the regions around the event…

Instrumentation and Methods for Astrophysics · Physics 2009-07-31 G. K. Skinner , J. F. Krizmanic

This paper presents a blind detection and compensation technique for camera lens geometric distortions. The lens distortion introduces higher-order correlations in the frequency domain and in turn it can be detected using higher-order…

Computer Vision and Pattern Recognition · Computer Science 2007-05-23 Lili Ma , YangQuan Chen , Kevin L. Moore
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