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The GREGOR adaptive optics system
Astronomische Nachrichten, 2012AbstractThe new 1.5‐m German solar telescope GREGOR at the Observatorio del Teide, Tenerife, is equipped with an integrated adaptive optics system. Although partly still in the commissioning phase, the system is already being used used for most science observations.
Th. Berkefeld +4 more
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Adaptation of adaptive optics systems
SPIE Proceedings, 1997The designs of existing Adaptive Optical System are "unadaptive" themselves, it means the parameters of the systems, such as subaperture diameter d, dynamic range of wavefront distortion correction, frequency bandwidth, etc., are fixed. Since these parameters were mainly decided according to some statistic values of atmospheric disturbance and detected
Xin Yu, Dazun Zhao, Li Chen
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Adaptive Optical Technologies for Optical Transmission Systems
Proceedings of the 18th Panhellenic Conference on Informatics, 2014The emerging popularity of bandwidth-starving applications (such as internet video, cloud storage etc) has lead to an exponential growth of the amount of data to be transmitted over long distances using optical fibre. Fibre transmission impairments, like chromatic dispersion (CD) remain a limiting factor on optical transmission and hence their ...
Maki Nanou +5 more
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Gain optimization for adaptive optics systems
Proceedings of the 2003 American Control Conference, 2003., 2004This paper presents an optimization procedure for selecting the best controller gain for an adaptive optics system. The procedure uses an ARX identification of the open loop atmospheric data to model the atmospheric effects and sensor noise. The closed loop system incorporates the adaptive optics system dynamics, the identified atmosphere model and the
Looze, DP, Merritt, N
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Dynamic characteristics of optical adaptive systems
Applied Optics, 1987The effect of time delay on characteristics of an optical adaptive system is considered. Classification of the optical adaptive systems as dynamic feedback systems has been made. Systems with constant delay, a highspeed adaptive system as well as a new class of systems, i.e., predicting adaptive systems, are investigated.
V E, Zuev, V P, Lukin
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Performance of a compact adaptive-optics system
Applied Optics, 2004The design of an adaptive-optics system for correction of a beam propagating through high-speed, unpredictable optical turbulence required the use of a robust controller rather than a conventional least-squares controller. We describe the 37-channel, 50-Hz adaptive-optical system and its performance (lambda/75 rms).
Benjamin West, Frazier +2 more
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On the rejection of vibrations in adaptive optics systems
SPIE Proceedings, 2012In modern adaptive optics systems, lightly damped sinusoidal oscillations resulting from telescope structural vibrations have a significant deleterious impact on the quality of the image collected at the detector plane. Such oscillations are often at frequencies beyond the bandwidth of the wave-front controller that therefore is either incapable of ...
MURADORE, Riccardo +3 more
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Isoplanatism in a multiconjugate adaptive optics system
Journal of the Optical Society of America A, 2000Turbulence correction in a large field of view by use of an adaptive optics imaging system with several deformable mirrors (DM's) conjugated to various heights is considered. The residual phase variance is computed for an optimized linear algorithm in which a correction of each turbulent layer is achieved by applying a combination of suitably smoothed ...
A, Tokovinin, M, Le Louarn, M, Sarazin
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Dynamics of adaptive optical systems
Journal of the Optical Society of America A, 2010Dynamic (time) characteristics of adaptive systems are analyzed. A common adaptive system with a finite frequency band (or a finite response time) is described as a dynamic constant time-delay system, where time delay is to be much shorter than the time of coherence radius transfer through an optical beam by a mean wind speed. The questions of coherent
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Adaptive optical processing system with optical associative memory
Applied Optics, 1993An architecture for a novel adaptive optical processing system using optical associative memory with learning capability is proposed. The optical system consists of an optical preprocessor for feature extraction and optical associative memory. The feature-extraction ability can give excellent processing capability to the optical associative memory.
H, Toyoda +3 more
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