Three-dimensional correlation coefficient of speckle intensity for rectangular and circular apertures

Abstract

The average three-dimensional size of speckles produced by the illumination of optically rough surfaces with coherent laser light is determined from the autocorrelation function of intensity in space. Analytical and numerical results are given for rectangular and circular diffuser apertures. Important special cases are discussed and compared with available data from the literature. Several of the derived properties of the speckle patterns are stated for the first time and could lead to a greater accuracy of different speckle-interferometric measurement techniques.