COHERENT SCATTERING BY ONE-DIMENSIONAL RANDOMLY ROUGH METALLIC SURFACES

A critical evaluation of various theoretical techniques for calculatin g the reflectivity of one-dimensional metallic randomly rough surfaces is presented. We proceed by comparing experimental and rigorous numer ical results with those obtained with three perturbation theories and the Kirchhoff approximation. The samples were fabricated in photoresis t, and their metallized surface profiles constitute good approximation s to Gaussian-correlated, Gaussian random processes. The correlation l engths of these surfaces range from approximately one third to approxi mately three times the infrared wavelengths employed. The results show that the phase-perturbation theory has wider applicability than the o ther perturbation theories and tile results based on the Kirchhoff app roximation. (C) 1998 Optical Society of America.