Zobrazeno 1 - 10
of 27
pro vyhledávání: '"Roopashree, M. B."'
Publikováno v:
Journal of Communication & Computer, Vol. 8, No. 3, pp. 173-179, March 2011
We present the details of predicting atmospheric turbulence by mining Zernike moment data obtained from simulations as well as experiments. Temporally correlated optical wave-fronts were simulated such that they followed Kolmogorov phase statistics.
Externí odkaz:
http://arxiv.org/abs/1001.3295
Publikováno v:
Proceedings of ARTCom - 2009, IEEE Xplore, IEEE CS Digital Library
The performance metrics of different centroiding algorithms at low light level conditions were optimized in the case of a Shack Hartmann Sensor (SHS) for efficient performance of the adaptive optics system. For short exposures and low photon flux, th
Externí odkaz:
http://arxiv.org/abs/1001.1503
Publikováno v:
XXXIV Symposium of OSI, ICOP, 2009
Under a thin lens and paraxial approximation, the phase transformation function of a lens was simulated on a Liquid Crystal (LC) based Spatial Light Modulator (SLM). The properties of an array of such lenses simulated on transmitting type and reflect
Externí odkaz:
http://arxiv.org/abs/0911.0821
Publikováno v:
XXXIV Symposium of OSI, ICOP, 2009
The accuracy of wavefront reconstruction from discrete slope measurements depends on the sampling geometry, coherence length of the incoming wavefronts, wavefront sensor specifications and the accuracy of the reconstruction algorithm. Monte Carlo sim
Externí odkaz:
http://arxiv.org/abs/0911.0813
Publikováno v:
XXXIV Symposium of OSI, ICOP, 2009
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 simulations
Externí odkaz:
http://arxiv.org/abs/0911.0822
Publikováno v:
XXXIV Symposium of OSI, ICOP, 2009
The phase characteristics of reflecting and transmitting type twisted nematic liquid crystal based Spatial Light Modulators (SLMs) were measured using interferometry. Device parameters like contrast, brightness, input and output polarizer angles have
Externí odkaz:
http://arxiv.org/abs/0911.0817
Publikováno v:
XXXIV Symposium of OSI, ICOP, 2009
In adaptive optics, the measurement of spatial coherence length helps in deciding the optimum design parameters of a Shack Hartmann Sensor (SHS). Two methods of estimating the spatial coherence length of optical wavefronts are presented. The first me
Externí odkaz:
http://arxiv.org/abs/0911.0818
Publikováno v:
International Journal of Computer Applications,1(25):30-35, February 2010
Shack Hartmann wavefront sensor is a two dimensional array of lenslets which is used to detect the incoming phase distorted wavefront through local tilt measurements made by recording the spot pattern near the focal plane. Wavefront reconstruction is
Externí odkaz:
http://arxiv.org/abs/0910.3386
Publikováno v:
Ghosh, Ajay and Choudhury, Debesh eds., proceedings of International Conference on Trends in Optics and Photonics., March, 2009, Kolkata, India., pp. 318 - 330
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 in an ada
Externí odkaz:
http://arxiv.org/abs/0909.3413
Publikováno v:
International Journal of Power Control Signal and Computation(IJPCSC) Vol2. No.2, 2011, 128-131
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 correction syste
Externí odkaz:
http://arxiv.org/abs/0909.0711