Depolarization of light back scattered from rough dielectrics*

Abstract

The depolarization of light from a laser, back scattered from inhomogeneous dielectrics, was investigated both experimentally and theoretically. A theoretical model that includes back scattering from both the surface and subsurface was developed by use of the Kirchhoff approach. The subsurface polarized and depolarized back-scattered components are independent of surface roughness. The model predicts results in agreement with experimental measurements performed with a dual-polarized laser back-scattering system. The measurements indicate that a significant contribution to the total back-scattered power results from subsurface contributions; in some cases, this contribution completely masks the effects due to the surface.