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Aluminum mirrors are most commonly used for cryogenic optic systems. A parameter simulation has been conducted to design the aluminum mirror. We have obtained an optimized mirror structure after optimization applied in the mirror design stage. A finite element model analysis was conducted to predict the gravity sag, mounting-induced error and cryo-deformation of the mirror. Then we have fabricated a 160 mm diameter aluminum mirror based on the optimization results, tested it at room and cryogenic temperature. An error budget developed based on the experimental results shows that the fastening preloads effect dominates the surface figure of the aluminum mirror. The total deformation of the mirror surface at 100 K meets the optical requirement, which indicates that the optimized aluminum mirror is stable enough to retain good surface figure at cryogenic temperature and the aluminum mirror is promising for its cryogenic applications.

The image resolution is the most important performance parameter for an aerial optoelectronic sensor. Existing thermal control methods cannot eliminate the sensor&rsquo, s temperature gradient, making the image resolution difficult to further improve. This article analyzes the different impacts of temperature changes on the imaging resolution and proposes modifications. Firstly, the sensor was subjected to thermo-optical simulation by means of finite element analysis, and the different impacts of temperature changes on the imaging quality were analyzed. According to the simulation results, an active thermal control method is suggested to enhance the temperature uniformity of the sensor. Considering the impacts of active and passive thermal control measures, thermal optical analysis was carried out to predict the performance of the sensor. The results of the analysis show that the imaging quality of the sensor has been significantly improved. The experimental results show that the image resolution of the optoelectronic sensor improved from 47 to 59 lp/mm, which demonstrates that the sensor can produce a high image quality in a low-temperature environment.

In order to ensure the imaging performance of the aerial optoelectronic platform system in low temperature environment, an active-passive combined thermal control technology was studied. A thermal control finite element model of the aerial optoelectronic platform was established. Additionally, thermal control simulation analysis and experiments under extreme conditions were carried out respectively. The simulation and experimental results showed that the temperature level of the primary mirror is improved above 25 ℃ by the proposed thermal control technology effectively, meanwhile the temperature gradient of the primary and secondary mirrors are less than 5 ℃. The successful implementation of this active-passive combined thermal control technology provides a technical support for the precision thermal control of aerial optoelectronic platforms.