English
Related papers

Related papers: Pyramid wavefront sensor optical gains compensatio…

200 papers

Using five independent analytic and Monte Carlo simulation codes, we have studied the performance of wide field ground layer adaptive optics (GLAO), which can use a single, relatively low order deformable mirror to correct the wavefront…

Context. The diffusion of adaptive optics systems in astronomical instrumentation for large ground-based telescopes is rapidly increasing and the pyramid wavefront sensor is replacing the Shack-Hartmann as the standard solution for single…

Instrumentation and Methods for Astrophysics · Physics 2023-09-27 Guido Agapito , Enrico Pinna , Simone Esposito , Cedric Taïssir Heritier , Sylvain Oberti

We present the Wavefront Sensor units of the Gravity Plus Adaptive Optics (GPAO) system, which will equip all 8m class telescopes of the VLTI and is an instrumental part of the GRAVITY+ project. It includes two modules for each Wavefront…

The direct imaging and characterization of exoplanets requires extreme adaptive optics (XAO), achieving exquisite wavefront correction (upwards of 90$\%$ Strehl) over a narrow field of view (a few arcseconds). For these XAO systems the…

Instrumentation and Methods for Astrophysics · Physics 2024-07-17 J. Fowler , Rebecca Jensen-Clem , Maaike A. M. van Kooten , Vincent Chambouleyron , Sylvain Cetre

An adaptive optics system with a single deformable mirror is being implemented on the THEMIS 90cm solar telescope. This system is designed to operate in the visible and is required to be as robust as possible in order to deliver the best…

Instrumentation and Methods for Astrophysics · Physics 2021-01-11 Michel Tallon , Éric Thiébaut , Maud Langlois , Bernard Gelly , Richard Douet , Clémentine Béchet , Loïc Denis , Gil Moretto

We propose the Correlation-Locking Optimization SchEme (CLOSE), a real-time adaptive filtering technique for adaptive optics (AO) systems controlled with integrators. CLOSE leverages the temporal autocorrelation of modal signals in the…

Instrumentation and Methods for Astrophysics · Physics 2021-06-09 Vincent Deo , Éric Gendron , Fabrice Vidal , Milan Rozel , Arnaud Sevin , Florian Ferreira , Damien Gratadour , Nicolas Galland , Gérard Rousset

The performance of an adaptive optics (AO) system on a 100m diameter ground based telescope working in the visible range of the spectrum is computed using an analytical approach. The target Strehl ratio of 60% is achieved at 0.5um with a…

Astrophysics · Physics 2009-10-31 M. Le Louarn , N. Hubin , M. Sarazin , A. Tokovinin

High quality, repeatable point-spread functions are important for science cases like direct exoplanet imaging, high-precision astrometry, and high-resolution spectroscopy of exoplanets. For such demanding applications, the initial on-sky…

Instrumentation and Methods for Astrophysics · Physics 2021-07-19 Steven P. Bos , Michael Bottom , Sam Ragland , Jacques-Robert Delorme , Sylvain Cetre , Laurent Pueyo

The ESA Gaia spacecraft has two Shack-Hartmann wavefront sensors (WFS) on its focal plane. They are required to refocus the telescope in-orbit due to launch settings and gravity release. They require bright stars to provide good signal to…

Instrumentation and Methods for Astrophysics · Physics 2015-06-05 Alcione Mora , Amir Vosteen

There are scientific and technological needs to improve the co-phasing of the primary mirrors of segmented telescopes. We have developed a methodology for using the wavefront sensor of an adaptive optics (AO) system to disentangle the phase…

Instrumentation and Methods for Astrophysics · Physics 2025-03-05 Benjamin Calvin , Michael Fitzgerald , Sam Ragland

To reach the full potential of the new generation of ground based telescopes, an extremely fine adjustment of the phase is required. Wavefront control and correction before detection has therefore become one of the cornerstones of…

Instrumentation and Methods for Astrophysics · Physics 2022-10-25 Vincent Chambouleyron , Olivier Fauvarque , Cédric Plantet , Jean-François Sauvage , Nicolas Levraud , Mahawa Cissé , Benoît Neichel , Thierry Fusco

Laser guide star (LGS) wave-front sensing (LGSWFS) is a key element of tomographic adaptive optics system. However, when considering Extremely Large Telescope (ELT) scales, the LGS spot elongation becomes so large that it challenges the…

The challenges of high contrast imaging (HCI) for detecting exoplanets for both ground and space applications can be met with extreme adaptive optics (ExAO), a high-order adaptive optics system that performs wavefront sensing (WFS) and…

SAXO+ is a planned enhancement of the existing SAXO, the VLT/ SPHERE adaptive optics system, deployed on ESO's Very Large Telescope. This upgrade is designed to significantly enhance the instrument's capacity to detect and analyze young…

This work introduces the first closed-loop adaptive optics (AO) system capable of optically correcting aberrations in real-time without a guidestar or a wavefront sensor. Nearly 40 years ago, Cederquist et al. demonstrated that asymmetric…

Image and Video Processing · Electrical Eng. & Systems 2026-05-14 Weiyun Jiang , Haiyun Guo , Christopher A. Metzler , Ashok Veeraraghavan

The Zernike wavefront sensor (ZWFS) is a concept belonging to the wide class Fourier-filtering wavefront sensor (FFWFS). The ZWFS is known for its extremely high sensitivity while having a low dynamic range, which makes it a unique sensor…

Laser guide stars (LGS) are used in many adaptive optics systems to extend sky coverage. The most common wavefront sensor used in combination with a LGS is a Shack-Hartmann wavefront sensor (SHWFS). The Shack-Hartmann has a major…

Instrumentation and Methods for Astrophysics · Physics 2020-12-07 Sebastiaan Y. Haffert , Christoph U. Keller , Richard Dekany

We present numerical characterizations of the wavefront sensing performance for few-mode photonic lantern wavefront sensors (PLWFSs). These characterizations include calculations of throughput, control space, sensor linearity, and an…

Instrumentation and Methods for Astrophysics · Physics 2023-11-06 Jonathan Lin , Michael P. Fitzgerald , Yinzi Xin , Yoo Jung Kim , Olivier Guyon , Sergio Leon-Saval , Barnaby Norris , Nemanja Jovanovic

The nonlinear curvature wavefront sensor (nlCWFS) has been shown to be a promising alternative to existing wavefront sensor designs. Theoretical studies indicate that the inherent sensitivity of this device could offer up to a factor of 10…

Instrumentation and Methods for Astrophysics · Physics 2022-09-02 Stanimir Letchev , Jonathan Crass , Justin R. Crepp , Sam Potier

(abridged) Extreme adaptive optics (XAO) encounters severe difficulties to cope with the high speed (>1kHz), high accuracy and high order requirements for future extremely large telescopes. An innovative high order adaptive optics system…

Instrumentation and Methods for Astrophysics · Physics 2015-09-29 Christian Delacroix , Maud Langlois , Magali Loupias , Eric Thiébaut , Louisa Adjali , Jonathan Leger , Michel Tallon
‹ Prev 1 4 5 6 7 8 10 Next ›