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Related papers: Deformable mirror-based pupil chopping for exoplan…

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Dynamic wavefront aberrations negatively impact a wide range of optical applications including astronomy, optical free-space telecommunications and bio-imaging. Wavefront errors can be compensated by an adaptive optics system comprised of a…

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

Extra-solar planets have not been imaged directly with existing ground or space telescopes because they are too faint to be seen against the halo of the nearby bright star. Most techniques being explored to suppress the halo are achromatic,…

Astrophysics · Physics 2009-11-10 Johanan L. Codona , Roger Angel

Quasi-static aberrations in coronagraphic systems are the ultimate limitation to the capabilities of exoplanet imagers both ground-based and space-based. These aberrations - which can be due to various causes such as optics alignment or…

Instrumentation and Methods for Astrophysics · Physics 2019-07-31 Olivier Herscovici-Schiller , Jean-François Sauvage , Laurent M. Mugnier , Kjetil Dohlen , Arthur Vigan

Rather than using an adaptive optics (AO) system to correct a telescope s entire pupil, it can instead be used to more finely correct a smaller sub-aperture. Indeed, existing AO systems can be used to correct a sub-aperture 1/3 to 1/2 the…

Astrophysics · Physics 2009-11-13 E. Serabyn , K. Wallace , M. Troy , B. Mennesson , P. Haguenauer , R. Gappinger , R. Burruss

Multi-Conjugate Adaptive Optics (MCAO) is essential for increasing the corrected Field-of-View (FoV) in astronomical imaging and potentially for free-space optical communications, particularly for small-aperture, transportable systems. We…

Instrumentation and Methods for Astrophysics · Physics 2026-03-26 Tommaso Furieri , Stefano Bonora

The aberrations induced by the sample and/or by the sample holder limit the resolution of optical microscopes. Wavefront correction can be achieved using a deformable mirror with wavefront sensorless optimization algorithms but, despite the…

Many adaptive optics systems operate by measuring the distortion of the wavefront in one wavelength range and performing the scientific observations in a second, different wavelength range. One common technique is to measure wavefront…

Astrophysics · Physics 2009-11-07 Henry G. Roe

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

Extreme wavefront correction is required for coronagraphs on future space telescopes to reach 1e-8 or better starlight suppression for the direct imaging and characterization of exoplanets in reflected light. Thus, a suite of wavefront…

There are different techniques to sense the wavefront phase-distortions due to atmospheric turbulence. Curvature sensors are practical in their sensitivity being adjustable to the prevailing atmospheric conditions. Even at the best sites,…

Instrumentation and Methods for Astrophysics · Physics 2015-05-19 Aglae Kellerer , Mark Chun , Christ Ftaclas

A pupil plane wavefront reconstruction procedure is proposed based on analysis of a sequence of focal plane images corresponding to a sequence of random pupil plane phase probes. The developed method provides the unique nontrivial solution…

Instrumentation and Methods for Astrophysics · Physics 2018-11-13 Eugene Pluzhnik , Dan Sirbu , Ruslan Belikov , Eduardo Bendek , Vladimir N. Dudinov

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

The success of ground-based instruments for high contrast exoplanet imaging depends on the degree to which adaptive optics (AO) systems can mitigate atmospheric turbulence. While modern AO systems typically suffer from millisecond time lags…

Instrumentation and Methods for Astrophysics · Physics 2019-09-13 Rebecca Jensen-Clem , Charlotte Z. Bond , Sylvain Cetre , Eden McEwen , Peter Wizinowich , Sam Ragland , Dimitri Mawet , James Graham

The quality of images of the Sun obtained from the ground are severely limited by the perturbing effect of the turbulent Earth's atmosphere. The post-facto correction of the images to compensate for the presence of the atmosphere require…

Solar and Stellar Astrophysics · Physics 2018-12-05 A. Asensio Ramos , J. de la Cruz Rodriguez , A. Pastor Yabar

Future searches for biomarkers on habitable exoplanets will rely on telescope instruments that achieve extremely high contrast at small planet-to-star angular separations. Coronagraphy is a promising starlight suppression technique,…

Instrumentation and Methods for Astrophysics · Physics 2017-12-20 J. Mazoyer , L. Pueyo , M. N'Diaye , K. Fogarty , N. Zimmerman , L. Leboulleux , K. E. St. Laurent , R. Soummer , S. Shaklan , C. Norman

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

Over the past decade, the high-contrast observation of disks and gas giant planets around nearby stars has been made possible on ground-based instruments using extreme adaptive optics (XAO). While these facilities produce images with a…

Instrumentation and Methods for Astrophysics · Physics 2024-12-11 M. N'Diaye , A. Vigan , B. Engler , M. Kasper , K. Dohlen , S. Leveratto , J. Floriot , M. Marcos , C. Bailet , P. Bristow

Stellar coronagraphs rely on deformable mirrors (DMs) to correct wavefront errors and create high contrast images. Imperfect control of the DM limits the achievable contrast and, therefore, the DM control electronics must provide fine…

The need for both high quality images and lightweight structures is one of the main drivers in space telescope design. An efficient wavefront control system will become mandatory in future large observatories, retaining performance while…

Instrumentation and Methods for Astrophysics · Physics 2013-05-03 Marie Laslandes , Emmanuel Hugot , Marc Ferrari , Claire Hourtoule , Christian Singer , Christophe Devilliers , Celine Lopez , Frederic Chazallet
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