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Discrete-Time Model of an Adaptive Optics System
2007 American Control Conference, 2007The standard adaptive optics system can be viewed as a sampled-data feedback system with a continuous-time disturbance (the incident wavefront from the observed object) and discrete-time measurement noise. A common measure of the performance of adaptive optics systems is the time average of the pupil variance of the residual wavefront. This performance
Douglas P Looze
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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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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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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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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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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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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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Adaptive output regulation of the adaptive optics system
Journal of Vibration and Control, 2022Deformable mirrors are very efficient optical devices that are used in correcting wavefront aberrations and are core elements of adaptive optics systems. Its promising success allows it to operate in a large field of applications. Hence, one of the most important problems in the control of adaptive optics systems is to design a controller that can ...
Berk Altıner +2 more
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