<title>Use of power spectral density (PSD) to specify optical surfaces</title>

Abstract

The power spectral density (PSD) is the most appropriate way to characterize the microroughness of a surface with a spatial wavelength range from several centimeters to a few hundred nanometers. Novel concepts to specify optical surfaces using the PSD are discussed. The results are applied to measurements obtained by a n optical heterodyne profilometer, by a mechanical profiler nanostep, and by an atomic force microscope. It is demonstrated that this method could yield a bandwidth independent model for the description of surface parameters.