Mirror surface autocovariance functions and their associated visible scattering

Abstract

Visible scattering is measured and compared with predictions based upon surface roughness measurements. The results indicate two scales of roughness, a short scale of the order of 1 microm and a long scale ranging from 30 to 150 microm. A study of the relative amount of scattering from the two scales shows that the short scale accounts for all the scattering for scattering angles larger than 3 degrees . Furthermore, the analysis demonstrates the importance of spatial frequency bandwidth limits in optical scattering and finish measurements for a particular class of highly polished mirror surfaces.