Speckle correlations around the backscattering direction in the double-passage configuration

High-order correlations from rough-surface scattering

It is proposed to apply an optical setup of a randomly weak rough dielectric film on a reflecting metal substrate for the measurement of high-order correlations from rough-surface scattering. The angular amplitude and intensity correlations are measured. Because of multiple scattering, when the input laser beam size is comparatively small or close to the travel pass length inside the film, C(2) and C(3) are measured by subtraction of the amplitude correlation from the intensity correlation.