Stray light analysis and baffle design of remote sensing camera for microsatellite

Abstract

A two-mirror catadioptric system with corrective lens groups is adopted in the remote sensing camera of microsatellite. Compared with the refractive system, it has the advantage that its performance is hardly influenced by thermal environment. Stray light results in image blur and the contrast reduction of the camera. It is necessary to analyze and control it. In traditional way, stray light can be effectively suppressed with a long baffle, which is not suitable for microsatellites with limited space. And a compact one with high performance is designed. First of all, model of the camera is set up and its stray light is analyzed with Lighttools. The main and the primary baffles are designed and optimized. Then the point source transmittance is calculated to evaluate and verify the designs. Its veiling glare index is also simulated and calculated based on black-patch measurement.