Exact formula of effective solid angle of a rectangular cold screen seen by a FPA

摘要

Optimization of optronics sensors requires models that compute the effective solid angle of a cold screen as seen from any point in the focal plane. Until now, the problem has been theoretically solved for circular screen, and some works solved the problem for a linear detector arrays. This article presents the exact mathematical formula of the effective solid angle at any point in the focal plane, thus preventing digital integral computation on each pixel of a detector matrix.