Title: Anisotropic diffusion based on Fermi-Dirac distribution function and its application in the Shack-Hartman wavefront sensor
Authors: Yanyan Zhang; Chengsheng Pan; Luyao Wang; Suting Chen
Addresses: Department of Electronic and Information Engineering, Institute of Intelligent Network and Information System, Nanjing University of Information and Science Technology, Nanjing, 210044, China; Jiangsu Key Laboratory of Meteorological Observation and Information Processing, Nanjing, 210044, China; Jiangsu Technology and Engineering Center of Meteorological Sensor Network, Nanjing, 210044, China; Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Nanjing 210044, China ' Institute of Intelligent Network and Information System, Department of Electronic and Information Engineering, Nanjing University of Information and Science Technology, Nanjing, 210044, China ' Jiangsu Key Laboratory of Meteorological Observation and Information Processing, Nanjing, 210044, China; Jiangsu Technology and Engineering Center of Meteorological Sensor Network, Nanjing, 210044, China ' Jiangsu Key Laboratory of Meteorological Observation and Information Processing, Nanjing, 210044, China; Jiangsu Technology and Engineering Center of Meteorological Sensor Network, Nanjing, 210044, China
Abstract: In this study, the anisotropic diffusion technique is applied to estimate spots in the noise signals of the Shack-Hartmann wavefront sensor. Based on the analysis of the classical anisotropic diffusion function and on an improved algorithm, a diffusion function is proposed based on the Fermi-Dirac distribution. It is proved mathematically that the new function has a higher convergence speed and a better performance. Monte Carlo simulations are used to verify the applicability of the new function subject to the noise limit and signal level. The simulation and experimental results show that the anisotropic diffusion algorithm can effectively filter out the noise. The integrity of the spots can be maintained, and the centroid detection accuracy and signal-to-noise ratio are also improved.
Keywords: Shack-Hartmann wavefront sensor; noise; anisotropy; diffusion function.
DOI: 10.1504/IJSNET.2020.110462
International Journal of Sensor Networks, 2020 Vol.34 No.2, pp.95 - 105
Received: 09 Mar 2020
Accepted: 10 Mar 2020
Published online: 20 Oct 2020 *