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Related papers: Anisoplanatic errors in two-wavelength adaptive op…

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Two-wavelength adaptive optics (AO) systems sense turbulence-induced wavefront distortions using an artificial beacon or natural guidestar at one wavelength, while correcting and possibly transmitting at another. Although most existing AO…

Optics · Physics 2025-05-02 Milo W. Hyde , Matthew Kalensky , Mark F. Spencer

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 effects of anisoplanatism on the adaptive optics point spread function are investigated. A model is derived that combines observations of the guide star with an analytic formulation of anisoplanatism to generate predictions for the…

Astrophysics · Physics 2009-11-11 Matthew Britton

Wavefront of light passing through turbulent atmosphere gets distorted. This causes signal loss in free-space optical communication as the light beam spreads and wanders at the receiving end. Frequency and/or time division multiplexing…

Quantum Physics · Physics 2023-04-11 Kai Sum Chan , H. F. Chau

Adaptive optics (AO) is a powerful tool employed across various research fields, from aerospace to microscopy. Traditionally, AO has focused on correcting optical phase aberrations, with recent advances extending to polarisation…

Adaptive optics (AO) have been used to correct wavefronts to achieve diffraction limited point spread functions in a broad range of optical applications, prominently ground-based astronomical telescopes operating in near infra-red. While…

Instrumentation and Methods for Astrophysics · Physics 2018-10-03 Alexandre J. T. S. Mello , Antonin H. Bouchez , Andrew Szentgyorgyi , Marcos A. van Dam , Henrique Lupinari

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

Ground-based high contrast exoplanet imaging requires state-of-the-art adaptive optics (AO) systems in order to detect extremely faint planets next to their brighter host stars. For such extreme AO systems (with high actuator count…

Earth and Planetary Astrophysics · Physics 2022-08-02 J. Fowler , Maaike A. M. Van Kooten , Rebecca Jensen-Clem

One important frontier for astronomical adaptive optics (AO) involves methods such as Multi-Object AO and Multi-Conjugate AO that have the potential to give a significantly larger field of view than conventional AO techniques. A second key…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 S. Mark Ammons , Luke Johnson , Edward A. Laag , Renate Kupke , Donald T. Gavel , Brian J. Bauman , Claire E. Max

The next generation of large telescopes for direct imaging of exoplanets will require segmented primary mirrors. Over both long and short timescales, these telescopes experience segment misalignments which degrade the final science image.…

Future large space telescopes will be equipped with adaptive optics (AO) to overcome wavefront aberrations and achieve high contrast for imaging faint astronomical objects, such as earth-like exoplanets and debris disks. In contrast to AO…

Instrumentation and Methods for Astrophysics · Physics 2020-01-07 He Sun , N. Jeremy Kasdin , Robert Vanderbei

Adaptive optics (AO) systems have significantly improved astronomical imaging capabilities over the last decade, and are revolutionizing the kinds of science possible with 4-5m class ground-based telescopes. A thorough understanding of AO…

Ground-based direct imaging of exoplanets at high contrast requires precise correction of atmospheric turbulence using adaptive optics (AO). The planet-to-star contrast ratio at small angular separations from the host star is often limited…

In this paper, a novel two-dimensional super-resolution angle-of-departure (AoD) and angle-of-arrival (AoA) estimation technique is proposed for wideband millimeter-wave multiple-input multiple-output systems with cross-polarized antenna…

Information Theory · Computer Science 2017-02-09 Dalin Zhu , Junil Choi , Robert W. Heath

Exoplanet direct imaging using adaptive optics (AO) is often limited by non-common path aberrations (NCPAs) and aberrations that are invisible to traditional pupil-plane wavefront sensors (WFSs). This can be remedied by focal-plane (FP)…

Inhomogeneities in the refractive index of a biological sample can introduce phase aberrationsin microscopy systems, severely impairing the quality of images. Adaptive optics can be employed to correct for phase aberrations and improve…

The contrast performance of current eXtreme Adaptive Optics (XAO) systems can be improved by adding a second AO correction stage featuring its own wavefront sensor, deformable mirror, and real-time controller. We develop a dynamical model…

Instrumentation and Methods for Astrophysics · Physics 2022-01-28 Nelly Cerpa-Urra , Markus Kasper , Caroline Kulcsár , Henri-François Raynaud , Cedric Taïssir Heritier

High-contrast imaging systems using active control with adaptive optics (AO) are often limited by non-common path (NCP) aberrations that are seen only at the final science image. AO systems employing focal-plane wavefront sensors (FP-WFSs)…

Instrumentation and Methods for Astrophysics · Physics 2026-01-22 Aditya R. Sengupta , Lisa A. Poyneer , Benjamin L. Gerard , Rebecca Jensen-Clem , Aaron J. Lemmer

In astronomy and microscopy, distortions in the wavefront affect the dynamic range of a high contrast imaging system. These aberrations are either imposed by a turbulent medium such as the atmosphere, by static or thermal aberrations in the…

Instrumentation and Methods for Astrophysics · Physics 2015-06-18 Benjamin Pope , Nick Cvetojevic , Anthony Cheetham , Frantz Martinache , Barnaby Norris , Peter Tuthill

The behavior of an adaptive optics (AO) system for ground-based high contrast imaging (HCI) dictates the achievable contrast of the instrument. In conditions where the coherence time of the atmosphere is short compared to the speed of the…

Instrumentation and Methods for Astrophysics · Physics 2021-08-23 Maaike A. M. van Kooten , Rebecca Jensen-Clem , Sylvain Cetre , Sam Ragland , Charlotte Z. Bond , J. Fowler , Peter Wizinowich
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