Stray light analysis of the Formosat-5 telescope

Stray light analysis of FormoSat-5 telescope has been studied. The geometric contour profiles of the baffles are determined by checking the degree of blocked direct-incidence stray light. Trade-off between different baffle contours has been made by comparing the direct-incidence stray light, incident energy ratio, and incident energy uniformity of the focal plane assembly (FPA). Detail studies have then performed on the contribution of the stray light due to direct incidence, scattering from components, and multi-reflection between optical components. The effect of the FPA structure is also considered since it is the component adjacent the most to the FPA. In addition, the tolerance of the baffles fabrication and assembly are introduced.