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An obstacle to the detection of redshifted 21cm emission from the epoch of reionization (EoR) is the presence of foregrounds which exceed the cosmological signal in intensity by orders of magnitude. We argue that in principle it would be…

Weak gravitational lensing (WL) is one of the most powerful techniques to learn about the dark sector of the universe. To extract the WL signal from astronomical observations, galaxy shapes must be measured and corrected for the point…

Instrumentation and Methods for Astrophysics · Physics 2016-09-21 Andrés. A. Plazas , Charles A. Shapiro , Arun Kannawadi , Rachel Mandelbaum , Jason D. Rhodes , Roger Smith

Several telescopes include large Deformable Mirrors (DM) located directly inside the telescope. These adaptive telescopes trigger new constraints for the calibration of the Adaptive Optics (AO) systems as they usually offer no access to an…

Instrumentation and Methods for Astrophysics · Physics 2019-01-10 C. T. Heritier , S. Esposito , T. Fusco , B. Neichel , S. Oberti , R. Briguglio , G. Agapito , A. Puglisi , E. Pinna , P. -Y. Madec

The ingot WFS is a new kind of wavefront sensor specifically designed to deal with the elongation of LGS reference sources on ELT-class telescopes. Like the pyramid, it belongs to the family of pupil plane wavefront sensors and can be…

To directly image Earth-like planets, contrast levels of 10^-8 - 10^-10 are required. The next generation of instruments will need wavefront control below the nanometer level to achieve these goals. The Zernike wavefront sensor (ZWFS) is a…

Instrumentation and Methods for Astrophysics · Physics 2025-10-01 M. Darcis , S. Y. Haffert , V. Chambouleyron , D. S. Doelman , P. J. de Visser , M. A. Kenworthy

Wavelet phase is a critical parameter in seismic processing, where zero-phase wavelets are essential for maximizing temporal resolution and ensuring accurate interpretation of subsurface structures. In practice, however, the seismic wavelet…

Geophysics · Physics 2026-04-09 Ali Gholami

Adaptive optics (AO) system performance is improved using post-processing techniques, such as point spread function (PSF) deconvolution. The PSF estimation involves characterization of the different wavefront (WF) error sources in the AO…

Instrumentation and Methods for Astrophysics · Physics 2018-08-29 Florian Ferreira , Eric Gendron , Gérard Rousset , Damien Gratadour

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…

Phase wrapping is a major problem in direction-of-arrival (DOA) estimation using phase-difference observations. For a sensor pair with an inter-sensor spacing greater than half of the wavelength ($\lambda/2$) of the signal, phase wrapping…

Signal Processing · Electrical Eng. & Systems 2021-10-22 Hui Chen , Tarig Ballal , Tareq Y. Al-Naffouri

High-contrast imaging instruments need extreme wavefront control to directly image exoplanets. This requires highly sensitive wavefront sensors which optimally make use of the available photons to sense the wavefront. Here, we propose to…

Instrumentation and Methods for Astrophysics · Physics 2022-09-14 Rico Landman , Christoph Keller , Emiel H. Por , Sebastiaan Haffert , David Doelman , Thijs Stockmans

The ingot wavefront sensor (I-WFS) has been proposed, for ELT-like apertures, as a possible pupil plane WFS, to cope with the geometrical characteristics of a laser guide star (LGS). Within the study and development of such a WFS, on-going…

Astronomical adaptive optics (AO) is a critical approach to enable ground-based diffraction-limited imaging and high contrast science, with the potential to enable habitable exoplanet imaging on future extremely large telescopes. However,…

Instrumentation and Methods for Astrophysics · Physics 2024-06-18 Benjamin L. Gerard , Aaron Lemmer , Bautista R. Fernandez , Xiaoxing Xia , Cesar Laguna , Mike Kim , Stephen Mark Ammons , Brian Bauman , Lisa Poyneer

Accurate blur estimation is essential for high-performance imaging across various applications. Blur is typically represented by the point spread function (PSF). In this paper, we propose a physics-informed PSF learning framework for…

Computer Vision and Pattern Recognition · Computer Science 2025-03-12 Liqun Chen , Yuxuan Li , Jun Dai , Jinwei Gu , Tianfan Xue

Access to knowledge of the point spread function (PSF) of adaptive optics(AO)-assisted observations is still a major limitation when processing AO data. This limitation is particularly important when image analysis requires the use of…

Instrumentation and Methods for Astrophysics · Physics 2023-05-10 A. Lau , R. JL. Fétick , B. Neichel , O. Beltramo-Martin , T. Fusco

Increasing interest in astronomical applications of non-linear curvature wavefront sensors for turbulence detection and correction makes it important to understand how best to handle the data they produce, particularly at low light levels.…

Instrumentation and Methods for Astrophysics · Physics 2015-06-12 P. L. Aisher , J. Crass , C. Mackay

We propose to explore a cascade extreme Adaptive optics (ExAO) approach with a second stage based on a Zernike wavefront sensor (ZWFS) for exoplanet imaging and spectroscopy. Most exoplanet imagers currently use a single-stage ExAO to…

Instrumentation and Methods for Astrophysics · Physics 2023-09-20 Mamadou N'Diaye , Arthur Vigan , Byron Engler , Markus Kasper , Serban Leveratto , Johan Floriot , Michel Marcos , Christophe Bailet , Kjetil Dohlen

The high sensitivity of the pyramid wavefront sensor has made it the preferred sensor in high contrast adaptive optics systems. Future higher contrast systems, like the Extremely Large Telescope's Planetary Camera System, will require…

Instrumentation and Methods for Astrophysics · Physics 2026-01-14 Aurélie Magniez , Charlotte Z. Bond , Peter Wizinowich , TIm Morris , Kieran O'Brien

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

Ptychography has become prominent at synchrotron facilities worldwide for characterizing biological and material specimens' topological structures and properties at the nanometer or atomic scale, due to its lens - less, highly quantitative…

Image and Video Processing · Electrical Eng. & Systems 2025-01-28 Tao Liu , Bingyang Wang , JiangTao Zhao , Maik Kahnt , Fucai Zhang

MAPS, MMT Adaptive optics exoPlanet characterization System, is the upgrade of legacy 6.5m MMT adaptive optics system. It is an NSF MSIP-funded project that includes (i) refurbishing of the MMT Adaptive Secondary Mirror (ASM), (ii) new high…

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