Surface Roughness Dependence of the First-order Statistics of Polychromatic Speckle Patterns

A theoretical formula for the first-order probability density function of polychromatic speckle is presented, based on recent results for integrated laser speckle. We consider both completely and partially coherent incident light. An experimental set-up for accurate measurements of speckle statistics is described. Experimental results for the constrast and the probability density of polychromatic speckle in the far field show a significant dependence on surface roughness. Except from some high contrast values they agree fairly well with the theory.