Optical And Mechanical Structure Design Of A High Altitude Orbits Collimating Infrared Earth Simulator

In recent years, with the development of space technology, the infrared earth simulator that can only provide an earth angle could not meet the requirements of the calibration tests for earth sensor on the ground, then the research on infrared earth simulator which can provide a variety of earth angles has become an inevitable trend. Based on the the collimated infrared earth simulator's working principle and design requirements, aimed at these three orbit height 18000Km, 35786 Km and 42000 Km, a high altitude orbits collimating infrared earth simulator is developed by adopting the collimation and the earth diaphragm alterable project. Applied ZEMAX software to design a meniscus of germanium collimating lens, the simulation results show that the lens has a effective aperture of 240mm, provide the optimum position and diameter of the earth diaphragms correspond following three earth angles of 30.42 degrees, 17.46 degrees and 15.19 degrees. Used ANSYS software to do finite element analysis for the key components of the mechanical structure. Finally, validate the deviation accuracy of flare angles and beam parallelism via theoretical analysis and practical calculation. The results indicate that the errors of three flare angles of the earth are all less than +/- 0.05, can meet the accuracy requirements of infrared earth simulator for infrared earth sensor's calibration testing on the ground.