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Reseach Article

Centroid Detection by Gaussian Pattern Matching In Adaptive Optics

by Akondi Vyas, B R Prasad, M B Roopashree
International Journal of Computer Applications
Foundation of Computer Science (FCS), NY, USA
Volume 1 - Number 26
Year of Publication: 2010
Authors: Akondi Vyas, B R Prasad, M B Roopashree
10.5120/483-793

Akondi Vyas, B R Prasad, M B Roopashree . Centroid Detection by Gaussian Pattern Matching In Adaptive Optics. International Journal of Computer Applications. 1, 26 ( February 2010), 30-35. DOI=10.5120/483-793

@article{ 10.5120/483-793,
author = { Akondi Vyas, B R Prasad, M B Roopashree },
title = { Centroid Detection by Gaussian Pattern Matching In Adaptive Optics },
journal = { International Journal of Computer Applications },
issue_date = { February 2010 },
volume = { 1 },
number = { 26 },
month = { February },
year = { 2010 },
issn = { 0975-8887 },
pages = { 30-35 },
numpages = {9},
url = { https://ijcaonline.org/archives/volume1/number26/483-793/ },
doi = { 10.5120/483-793 },
publisher = {Foundation of Computer Science (FCS), NY, USA},
address = {New York, USA}
}
%0 Journal Article
%1 2024-02-06T19:48:48.407567+05:30
%A Akondi Vyas
%A B R Prasad
%A M B Roopashree
%T Centroid Detection by Gaussian Pattern Matching In Adaptive Optics
%J International Journal of Computer Applications
%@ 0975-8887
%V 1
%N 26
%P 30-35
%D 2010
%I Foundation of Computer Science (FCS), NY, USA
Abstract

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 performed in two stages - (a) image centroiding to calculate local slopes, (b) formation of the wavefront shape from local slope measurement. Centroiding accuracy contributes to most of the wavefront reconstruction error in Shack Hartmann sensor based adaptive optics system with readout and background noise. It becomes even more difficult in atmospheric adaptive optics case, where scintillation effects may also occur. In this paper we used a denoising technique based on thresholded Zernike reconstructor to minimize the effects due to readout and background noise. At low signal to noise ratio, this denoising technique can be improved further by taking the advantage of the shape of the spot. Assuming a Gaussian pattern for individual spots, it is shown that the centroiding accuracy can be improved in the presence of strong scintillations and background.

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Index Terms

Computer Science
Information Sciences

Keywords

Adaptive Optics Shack Hartmann Sensor Wavefront Reconstruction Centroiding