Open AccessClipped speckle autocorrelation metric for spot size characterization of focused beam on a diffuse target
Author(s) -
Yuanyang Li,
Jin Guo,
Lisheng Liu,
Tingfeng Wang,
Taotao Wei,
Zhenhua Jiang
Publication year - 2015
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.23.007424
Subject(s) - speckle pattern , autocorrelation , optics , metric (unit) , computer science , physics , mathematics , statistics , operations management , economics
The clipped speckle autocorrelation (CSA) metric is proposed for estimating the laser beam energy concentration on a remote diffuse target in a laser beam projection system with feedback information. Using the second order statistics of the intensity distribution of the fully developed speckle and the relation of the autocorrelation functions for the clipped and unclipped speckles, we present the theoretical expression of this metric as a function of the normalized CSA function. The simulation technique based on the equivalence of the spatial average and the ensemble time average is provided. Based on this simulation technique, we analyze the influence of the surface roughness of the target on this metric and then show the influencing factors of the metric performance, for example the finite sample effect and aperture size of the observation system. Experimental results are illustrated to examine the capability of this metric and the correctness of the discussion about the metric performance.