Statistical properties of speckle intensity variations in the diffraction field under illumination of partially coherent light

Abstract

The statistical properties of speckle intensity variations produced by partially spatially coherent light in the diffraction and image field of a diffusely transmitting object are studied experimentally with intimate connection to its surface roughness. The probability distribution and the average contrast of intensity variations in speckle patterns are investigated as a function of the surface roughness of the object and the position of a receiving plane. It becomes clear that the statistical properties of speckles strongly depend not only on the surface roughness of the object and the spatial coherence of illumination but also on the position of the receiving plane.