Thermal integration analysis of optical machines for space-based laser communications

Temperature is one of the main factors affecting the normal operation of the optical system of laser communication equipment. Based on the requirements of the air-based platform for the surface shape index of airborne communication equipment, the optical-mechanical thermal integration analysis method is used to analyze the optical system of an airborne communication optical machine. Firstly, the finite element model of the air-based laser communication prototype is established. Secondly, the temperature field distribution and thermal deformation characteristics of the optical system structure during the full-load operation of the communication prototype are extracted by Ansys Workbench finite element analysis software, and the surface shape changes of the primary and secondary mirrors of the beam expansion system under the action of the heat source load are obtained. Finally, the optical software program SigFit is used for Zernike polynomial fitting, and the performance of the laser communication prototype beam expansion system is evaluated according to the fitting results. The results show that the maximum axial displacement of the primary and secondary mirrors of the beam expansion system is less than 0.02mm under both horizontal and vertical conditions of the optical axis when the communication optical machine is fully loaded at an ambient temperature of 22℃, and the mirror surface shape is better than λ/50, which meets the performance index and can adapt to the temperature environment requirements of airborne communication equipment on air-based platforms.