Optical System Design Of Geostationary Orbit Ocean Imager

China is a big marine country in the world, and often suffers from sea disasters. Hence, strategic status of ocean is very important to the construction of our country's social economy and national defence. Using space based remote sensing technology, particularly Ocean Satellite, to monitor marine can reduce ocean disasters and supply fluent ocean remote sensing data. At present, all Ocean Satellite in operation are on Sunsynchronous orbit. Their cover period are so long that it cannot meet the requirement of real-time surveillance of our country's marginal sea. Whereas, cover period of the ocean satellite on Geosynchronous orbit can reach several hours or even shorter than an hour. Thus it can fulfil the need of real-time monitoring of ocean disasters and contingencies. In a word, research and development of Geosynchronous orbit Ocean Imager has great economic effect and social benefit.The main payload of Ocean Satellite is Ocean Imager of which Optical system is an important part. It must be compact and reliable because of satellite's rigid restrict of weight and size. According to the technical specifications and environment requirenment, optical system overall scheme was projected. Linear detector was selected as the imaging device. Basic parameters of optical system were calculated and detected energy, S /N ratio, NEΔρand NEΔT were analysed. Each index met the overall specifications.We compaired several common optics of remote sensing camera and generalized their merits and faults. And selected off-axis three-mirror structure at last. Coaxial three-mirror system theory was analysed and a new method of solving primitive parameters was deduced. Using MatLab we figured out the initial configuration of optics.Front System and two IR Relay System were designed using Code V. We analysed the image quality which met the requirement. Combining MTF and wavefront error we analysed optics'tolerance which was loose and can reduce difficulty of manufacturing and alignment.Finally, the size of scan mirror was calculated and SiC was selected as substrate material of scan mirror and reflective mirror. Spectral filtering system was analysed. We used filter wheel as the splitting system of Visble-NIR band, which can decrease the complexity of splitting system.