Abstract

Near specular scatter from imaging optics can be the key factor limiting resolution. This is especially true for large diameter space based telescopes that do not have to contend with atmospheric distortion and are capable (in principle) of resolving very tight diffraction limited points. This paper discusses a laboratory technique to measure, and/or calculate, the near specular BRDF of such optics so that manufacturing techniques of low scatter mirrors can be optimized and final product can be checked. The technique was conceived in response to a government lab interested in measuring to "a few arc seconds from specular."

© 1992 Optical Society of America