Optimal Design of TIR Prism for the Infrared Target Simulator based on DMD

摘要

Overall structure of the infrared target simulator system and the principle of DMD are introduced. When DMD is on "open" state, all of the incidence light can rip into the pupil of the projection system, In addition, when it is on "close" state or "flat" state, all of the incident light can't rip into the pupil of the projection system. Based on this principle, with a specific infrared target simulator, TIR prism with BaF_2 as material is designed. And then, this design is improved by ZnSe material instead of BaF_2. ZnSe transmission rate is very well in the range of 0.6 microns to 14 microns and the infrared target simulator in this project requires 3 to 5 microns and 8 to 14 microns wavelength. This material is hard and easy to be processed. The design idea and design process are introduced in details in this paper and angle parameters are obtained. To improve light utilization and image quality in infrared target simulator system, two types of thin film on TIR prism different surfaces are designed. One is high transmittance with incidence angle of 0° and 24°, the other is 55°. Finally, this scheme is simulated and optimized by Tracepro software. Approving results were acquired.