Oct 1, 1990
Journal name not available for this finding
Scatter from beryllium mirrors often seems to be higher than expected based on mirror surface foughness data. The paper verifies the effects and shows that in addition to surface topography scatter is caused by mirror defects that are non-topographic in nature (subsurface flaws, optical contant variations across grain boundaries, etc.). This effect is more severe in them id IR than the visible because non-topographical scatter tends to scale as inverse wavelengths for several materials is presented and analyzed. Beryllium is found to be especially prone to these problems. The conclusion is reached, that a profile (or roughness) requirement is not sufficent speciefication to achieve low scatter space mirrors.