Optical System Design And Stray Light Analysis Of Micro Video-capable Satellite

The video-capable satellite is a new type of earth observation satellite. One class of low orbit micro video-capable satellites with flat panel detector are booming. These satellites comprehensive utilize the advanced agile satellite platform to realize staring observation. The low orbit micro video-capable satellite has a light weight and small size. Its imaging optical system is refractive/reflective system with long focal length and wide field of view. The optical system designed in this paper simplifies the optical system structure of the micro video satellite, and the design of the shading system could meet the requirements of eliminating stray light.The main content of this dissertation are that:1) In this paper, the development of micro video-capable satellite at home and abroad was introduced, and the optical system parameters were analyzed and summarized. The basic structure of the optical system was determined, and the two mirror optical system was designed to meet the requirements of the system design.2) In order to reduce the asphericity of the secondary mirror of two-mirror refractive/reflective system, I designed an optical system with a Margin-like mirror as the secondary mirror. The optical system with a Margin-like mirror smaller size, shorter processing cycle, better imaging quality, met the requirements of micro video satellite optical system.3) In order to reduce the number of the correcting refracted lens, I designed an optical system with only one axial gradient-index(AGRIN) lens as correcting refracted lens. This design had opened up a new idea of the two-mirror refractive/reflective system for lighter and simpler. In this design, a single axial gradient index lens was used instead of 3 pieces of uniform material lenses.4) Stray light analysis of two-mirror refractive/reflective optical system was given. Its opto-mechanic model was established with Unigraphics(UG) software. And lens hood in the main mirror, lens hood outside and window shade, lens hool in the secondly mirror were designed by UG modeling, too. This design result was tested by light tracing in simulating software Tracepro, which showed the PST value of every view meet the requirements. This proved the feasibility of the stray light eliminating design.In this paper, I designed two-mirror refractive/reflective system which meet micro video-capable satellite optical camera index. And I have given two optimum design methods, which used the Margin-like mirror and the AGRIN lens respectively. Through opto-mechanic model, the shading system of the camera was designed. This design result was tested to meet the design requirements by light tracing in simulating software Tracepro.