The flux distribution resulting from the light from an emitting surface being scattered by reflection from an irregular mirror surface is formulated. The particular case of the limb-darkened sun, a parabolic mirror, and a plane focal surface are analyzed using an example of geometrical scattering that occurs for thin metal optical surfaces possessing a show-through due to honeycomb backing. A matrix algorithm for computing the flux distribution is developed.
JAMES N. HANSON, "Analysis of Irregular Reflectors," J. Opt. Soc. Am. 56, 741-745 (1966)