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Direct detection of exoplanets requires high dynamic range imaging. Coronagraphs could be the solution, but their performance in space is limited by wavefront errors (manufacturing errors on optics, temperature variations, etc.), which…

Instrumentation and Methods for Astrophysics · Physics 2015-05-14 Raphael Galicher , Pierre Baudoz , Gerard Rousset , Julien Totems , Marion Mas

The direct detection of extrasolar planets by imaging means is limited by the large flux of light from the host star being scattered into the region of interest by a variety of processes, including diffraction. Coronagraphs are devices that…

Astrophysics · Physics 2009-11-10 James P. Lloyd , Anand Sivaramakrishnan

The RISTRETTO instrument, a proposed visible high-contrast, high-resolution spectrograph for the VLT, has the primary science goal of detecting reflected light from nearby exoplanets and characterizing their atmospheres. Specifically, it…

Instrumentation and Methods for Astrophysics · Physics 2024-09-09 Muskan Shinde , Nicolas Blind , Christophe Lovis

Shack-Hartmann wavefront sensors for both solar and laser guide star adaptive optics (with elongated spots) need to observe extended objects. Correlation techniques have been successfully employed to measure the wavefront gradient in solar…

Instrumentation and Methods for Astrophysics · Physics 2018-09-11 M. J. Townson , G. D Love , C. D. Saunter

With an extremely high dimensionality, the spatial degree of freedom of entangled photons is a key tool for quantum foundation and applied quantum techniques. To fully utilize the feature, the essential task is to experimentally…

Gravitationally lensed systems allow a detailed view of galaxies at high redshift. High spatial- and spectral-resolution measurements of arc-like structures can offer unique constraints on the physical and dynamical properties of high-z…

We present a reference-free computational wavefront sensor based on binary amplitude modulation and phase retrieval. The method employs Digital Micro-mirror Device as a programmable amplitude modulator and reconstructs the complex optical…

Optics · Physics 2026-02-12 Ondrej Denk , Jan Pilar , Martin Divoky , Miroslav Cech , Tomas Mocek

Wavefront sensors encode phase information of an incoming wavefront into an intensity pattern that can be measured on a camera. Several kinds of wavefront sensors (WFS) are used in astronomical adaptive optics. Amongst them, Fourier-based…

The presence of a scattering medium in the imaging path between an object and an observer is known to severely limit the visual acuity of the imaging system. We present an approach to circumvent the deleterious effects of scattering, by…

Wavefront shaping is a powerful technique that can be used to focus light through scattering media, which can be important for imaging through scattering samples such as tissue. The method is based on the assumption that the field at the…

Wavefront sensors are an important tool to characterize coherent beams of extreme ultraviolet radiation. However, conventional Hartmann-type sensors do not allow for independent wavefront characterization of different spectral components…

Instrumentation and Detectors · Physics 2018-04-04 L. Freisem , G. S. M. Jansen , D. Rudolf , K. S. E. Eikema , S. Witte

Gravitational waves (GWs) can be deflected, similarly to electromagnetic (EM) waves, by massive objects through the phenomenon of gravitational lensing. The importance of gravitational lensing for GW astronomy is becoming increasingly…

General Relativity and Quantum Cosmology · Physics 2024-04-08 Eungwang Seo , Tjonnie Guan Feng Li , Martin Anthony Hendry

To recognize gravitational wave lensing events and being able to differentiate between similar lens models will be of crucial importance once one will be observing several lensing events of gravitational waves per year. In this work, we…

Cosmology and Nongalactic Astrophysics · Physics 2021-12-03 Paolo Cremonese , David F. Mota , Vincenzo Salzano

State-of-the-art adaptive optics (AO) systems perform non-linear Fourier-type wavefront sensing for real-time corrections of dynamic wavefront aberrations. This general class of sensors uses a filtering mask in the focal plane that converts…

Instrumentation and Methods for Astrophysics · Physics 2025-06-24 Victoria Laidlaw

The photonic lantern (PL) is a tapered waveguide that can efficiently couple light into multiple single-mode optical fibers. Such devices are currently being considered for a number of tasks, including the coupling of telescopes and…

Instrumentation and Methods for Astrophysics · Physics 2022-09-28 Jonathan Lin , Michael Fitzgerald , Yinzi Xin , Olivier Guyon , Sergio Leon-Saval , Barnaby Norris , Nemanja Jovanovic

Wavefront shaping is a technique to study and control light transport inside scattering media. Wavefront shaping is considered to be applicable to any complex material, yet in most previous studies, the only sample geometries that are…

Wavefront sensing and control are important for enabling one of the key advantages of using large apertures, namely higher angular resolutions. Pyramid wavefront sensors are becoming commonplace in new instrument designs owing to their…

Instrumentation and Methods for Astrophysics · Physics 2019-03-20 Julien Lozi , Nemanja Jovanovic , Olivier Guyon , Mark Chun , Shane Jacobson , Sean Goebel , Frantz Martinache

We introduce in this article a general formalism for Fourier based wave front sensing. To do so, we consider the filtering mask as a free parameter. Such an approach allows to unify sensors like the Pyramid Wave Front Sensor (PWFS) and the…

Instrumentation and Methods for Astrophysics · Physics 2016-12-02 Olivier Fauvarque , Benoit Neichel , Thierry Fusco , Jean-François Sauvage , Orion Girault

When observing from the ground one has to deal with the turbulence from the atmosphere and the turbulence caused by the telescope's surroundings. In order to find the best sites for future solar telescopes and develop multi-conjugate…

Solar and Stellar Astrophysics · Physics 2011-03-23 Maria Tham

Gravitational waves propagate along null geodesics like light rays in the geometrical optics approximation, and they may have a chance to suffer from gravitational lensing by intervening objects, as is the case for electromagnetic waves.…

General Relativity and Quantum Cosmology · Physics 2010-10-12 Yousuke Itoh , Toshifumi Futamase , Makoto Hattori
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