DEPOLARIZATION OF SPECULAR SCATTER AS AN AID TO DISCRIMINATING BETWEEN A ROUGH DIELECTRIC SURFACE AND AN IDENTICAL ROUGH METALLIC SURFACE

A globally flat, locally rough, reflecting surface scatters incident radiation in all angular directions. The surface properties are described by a Mueller Matrix. Many elements the matrix are always zero, or only sometimes zero, depending on the material and the angle of incidence and detection. An experiment that measures how the nonzero elements change with angles of incidence and scatter for two rough surfaces whose surface profiles have the same statistics is described; however, one is a conductor and the other is a nonconductor. The actual results for the experimental geometry in which the angle, where the scattered radiation is detected, is equal and opposite to the angle of incidence (called specular scatter) are given. It is believed that the differences are primarily dependent on the material properties, rather than surface roughness, and that the differences are sufficiently gross to enable them to distinguish a conducting from a nonconducting rough surface.