Exact multiple scattering of waves from random rough surfaces: Speckle contrast

An exact formula for the mean multiple scattered intensity is presented by using normal statistics, as well as a gaussian correlation function, for the random rough surface in the limit of large correlation distance, T → ∞. Comparisons with the Kirchoff-Beckman approximation are also done. Further, we obtain an exact expression for the speckle contrast which explains experimental data and draws conclusions on the physical properties of the surface. © 1980.