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Astronomers working with faint targets will benefit greatly from improved image quality on current and planned ground-based telescopes. At present, most adaptive optic systems are targeted at the highest resolution with bright guide stars.…

Instrumentation and Methods for Astrophysics · Physics 2020-01-30 Craig Mackay

An adaptive guidance system suitable for the terminal phase trajectory of a hypersonic strike weapon is optimized using reinforcement meta learning. The guidance system maps observations directly to commanded bank angle, angle of attack,…

Systems and Control · Electrical Eng. & Systems 2021-10-19 Brian Gaudet , Roberto Furfaro

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

Optical turbulence, driven by fluctuations of the atmospheric refractive index, poses a significant challenge to ground-based optical systems, as it distorts the propagation of light. This degradation affects both astronomical observations…

Instrumentation and Methods for Astrophysics · Physics 2026-03-26 Mary Joe Medlej , Rahul Srinivasan , Simon Prunet , Aziz Ziad , Christophe Giordano

Wavefront shaping systems aim to image deep into scattering tissue by reshaping incoming and outgoing light to correct aberrations caused by tissue inhomogeneity However, the desired modulation depends on the unknown tissue structure and…

Optics · Physics 2026-01-14 Sagi Monin , Marina Alterman , Anat Levin

Classical navigation systems typically operate using a fixed set of hand-picked parameters (e.g. maximum speed, sampling rate, inflation radius, etc.) and require heavy expert re-tuning in order to work in new environments. To mitigate this…

Robotics · Computer Science 2020-11-03 Zifan Xu , Gauraang Dhamankar , Anirudh Nair , Xuesu Xiao , Garrett Warnell , Bo Liu , Zizhao Wang , Peter Stone

We present a liquid crystal method of correcting the phase of an aberrated wavefront using a spatial light modulator. A simple and efficient lab model has been demonstrated for wavefront correction. The crux of a wavefront correcting system…

Instrumentation and Methods for Astrophysics · Physics 2009-10-11 Akondi Vyas , M. B. Roopashree , Ravinder Kumar Banyal , B. Raghavendra Prasad

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

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…

The Adaptive Optics (AO) performance significantly depends on the available Natural Guide Stars (NGSs) and a wide range of atmospheric conditions (seeing, Cn2, windspeed,...). In order to be able to easily predict the AO performance, we…

We consider the mathematical background of the wavefront sensor type that is widely used in Adaptive Optics systems for astronomy, microscopy, and ophthalmology. The theoretical analysis of the pyramid sensor forward operators presented in…

Instrumentation and Methods for Astrophysics · Physics 2019-05-01 Victoria Hutterer , Ronny Ramlau , Iuliia Shatokhina

Transmission electron microscopes (TEMs) enable atomic-scale imaging but suffer from aberrations caused by lens imperfections and environmental conditions, reducing image quality. These aberrations can be compensated by adjusting…

Systems and Control · Electrical Eng. & Systems 2026-04-20 Jilles S. van Hulst , Erik M. Franken , Bart J. Janssen , W. P. M. H. Heemels , Duarte J. Antunes

We use Reinforcement Meta Learning to optimize an adaptive guidance system suitable for the approach phase of a gliding hypersonic vehicle. Adaptability is achieved by optimizing over a range of off-nominal flight conditions including…

Robotics · Computer Science 2021-08-02 Brian Gaudet , Kris Drozd , Ryan Meltzer , Roberto Furfaro

Adaptive regularization methods pre-multiply a descent direction by a preconditioning matrix. Due to the large number of parameters of machine learning problems, full-matrix preconditioning methods are prohibitively expensive. We show how…

Machine Learning · Computer Science 2020-11-19 Naman Agarwal , Brian Bullins , Xinyi Chen , Elad Hazan , Karan Singh , Cyril Zhang , Yi Zhang

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

The inversion of ring fit parameters to obtain subsurface flow maps in ring-diagram analysis for 8 years of SDO observations is computationally expensive, requiring ~3200 CPU hours. In this paper we apply machine learning techniques to the…

Solar and Stellar Astrophysics · Physics 2019-02-06 Rasha Alshehhi , Chris S. Hanson , Laurent Gizon , Shravan Hanasoge

We present an analytical derivation of the on-axis performance of Adaptive Optics systems using a given number of guide stars of arbitrary altitude, distributed at arbitrary angular positions in the sky. The expressions of the residual…

Instrumentation and Methods for Astrophysics · Physics 2015-06-17 E. Tatulli , A. N. Ramaprakash

Adaptive optics (AO) is critical in astronomy, optical communications and remote sensing to deal with the rapid blurring caused by the Earth's turbulent atmosphere. But current AO systems are limited by their wavefront sensors, which need…

Instrumentation and Methods for Astrophysics · Physics 2020-10-23 Barnaby R. M. Norris , Jin Wei , Christopher H. Betters , Alison Wong , Sergio G. Leon-Saval

The use of laser guide stars in astronomical adaptive optics results in elongated Shack-Hartmann wavefront sensor image patterns. Image correlation techniques can be used to determine local wavefront slope by correlating each sub-aperture…

Instrumentation and Methods for Astrophysics · Physics 2014-03-05 Alastair Basden

Adaptive optics can be used to mitigate the effects of atmospheric turbulence on imaging systems, but the correction is only partial, and deconvolution is often required to improve the resolution. This results in entire optical/digital…

Instrumentation and Methods for Astrophysics · Physics 2026-02-09 Florian Cheyssial , Laurent Mugnier , Cyril Petit
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