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Nullifying the servo bandwidth errors improves the strehl ratio by a substantial quantity in adaptive optics systems. An effective method for predicting atmospheric turbulence to reduce servo bandwidth errors in real time closed loop…

Instrumentation and Methods for Astrophysics · Physics 2011-09-14 Akondi Vyas , M B Roopashree , B Raghavendra Prasad

Servo lag errors in adaptive optics lead to inaccurate compensation of wavefront distortions. An attempt has been made to predict future wavefronts using data mining on wavefronts of the immediate past to reduce these errors. Monte Carlo…

Instrumentation and Methods for Astrophysics · Physics 2009-11-08 Akondi Vyas , M B Roopashree , B Raghavendra Prasad

Orbital angular momentum of photons is an intriguing system for the storage and transmission of quantum information, but it is rapidly degraded by atmospheric turbulence. We explore the ability of adaptive optics to compensate for this…

Quantum Physics · Physics 2016-12-09 Jose Raul Gonzalez Alonso , Todd Brun

An analytical expression is given for the minimum of the time-delay induced wavefront error (also known as the servo-lag error) in Adaptive Optics systems under temporal prediction filtering. The analysis is based on the von K\'arm\'an…

Instrumentation and Methods for Astrophysics · Physics 2020-06-22 Niek Doelman

Numerical simulations of atmospheric turbulence and AO wavefront correction are performed to investigate the timescale for fringe motion in optical interferometers with spatial filters. These simulations focus especially on partial AO…

Astrophysics · Physics 2009-11-11 Robert Tubbs

Optical imaging quality can be severely degraded by system and sample induced aberrations. Existing adaptive optics systems typically rely on iterative search algorithm to correct for aberrations and improve images. This study demonstrates…

The efficiency of the management of top-class ground-based astronomical facilities supported by Adaptive Optics (AO) relies on our ability to forecast the optical turbulence (OT) and a set of relevant atmospheric parameters. Indeed, in…

Instrumentation and Methods for Astrophysics · Physics 2020-06-14 E. Masciadri , G. Martelloni , A. Turchi

Simulating atmospheric turbulence is an essential task for evaluating turbulence mitigation algorithms and training learning-based methods. Advanced numerical simulators for atmospheric turbulence are available, but they require evaluating…

Optics · Physics 2020-06-24 Nicholas Chimitt , Stanley H. Chan

Recovering the turbulence-degraded point spread function from a single intensity image is important for a variety of imaging applications. Here, a deep learning model based on a convolutional neural network is applied to intensity images to…

Image and Video Processing · Electrical Eng. & Systems 2023-06-28 Abu Bucker Siddik , Steven Sandoval , David Voelz , Laura E Boucheron , Luis Varela

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

The image degradation produced by atmospheric turbulence and optical aberrations is usually alleviated using post-facto image reconstruction techniques, even when observing with adaptive optics systems. These techniques rely on the…

Instrumentation and Methods for Astrophysics · Physics 2015-05-18 A. Asensio Ramos , A. Lopez Ariste

Estimators of outer scales of atmospheric turbulence usually fit the phase screen snapshots derived from local wave front sensors to a Zernike basis, and then compare the spectrum of expansion coefficients in this basis with a narrowing…

Instrumentation and Methods for Astrophysics · Physics 2010-11-05 Richard J. Mathar

In the context of adaptive optics for astronomy, one can rely on the statistics of the turbulent phase to assess a part of the system's performance. Temporal statistics with one source and spatial statistics with two sources are well-known…

Instrumentation and Methods for Astrophysics · Physics 2022-09-05 Cédric Plantet , Giulia Carlà , Guido Agapito , Lorenzo Busoni

Recent progress in neuroscience to image and investigate brain function has been made possible by impressive developments in optogenetic and opto-molecular tools. Such research requires advances in optical techniques for the delivery of…

The estimation of atmospheric turbulence parameters is of relevance for: a) site evaluation & characterisation; b) prediction of the point spread function; c) live assessment of error budgets and optimisation of adaptive optics performance;…

Instrumentation and Methods for Astrophysics · Physics 2018-12-19 Paulo P. Andrade , Paulo J. V. Garcia , Carlos M. Correia , Johann Kolb , Maria Inês Carvalho

For high contrast imaging systems, the time delay is one of the major limiting factors for the performance of the extreme adaptive optics (AO) sub-system and, in turn, the final contrast. The time delay is due to the finite time needed to…

Instrumentation and Methods for Astrophysics · Physics 2019-04-08 Maaike van Kooten , Niek Doelman , Matthew Kenworthy

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

Forecast of optical turbulence and atmospheric parameters relevant for ground-based astronomy is becoming an important goal for telescope planning and AO instruments optimization in several major telescope. Such detailed and accurate…

Instrumentation and Methods for Astrophysics · Physics 2022-10-21 A. Turchi , E. Masciadri , L. Fini

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

We design an optical feedback network making use of machine learning techniques and demonstrate via simulations its ability to correct for the effects of turbulent propagation on optical modes. This artificial neural network scheme only…

Signal Processing · Electrical Eng. & Systems 2018-06-22 Sanjaya Lohani , Ryan T. Glasser
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