在极端低温情况下, 为保证高空相机镜头光学系统温度满足设计要求, 结合被动热控和主动热控进行相机光机系统的热设计.以聚酰亚胺为隔热材料进行被动热控, 增大相机内部与外界的热阻, 减弱外界低温环境对镜头温度的影响.采用电加热膜加热对相机镜头进行主动热控, 在WorkBench有限元软件中建立镜头和窗口组件的传热模型, 分析载荷构成, 加载加热功率载荷、热对流载荷和热辐射载荷, 进行稳态热分析.结果表明, 在六个加热区, 当加热功率分别为12、17、22、17、10、13 W时, 相机光学系统的温度控制在18℃～22℃范围内, 满足热控设计要求.

To guarantee the image quality of a high-altitude camera in extreme low temperatures, thermal design for camera optical system was done by combined passive thermal control with active thermal control. Polyimide insulation material is used for passive thermal control, increasing the camera's thermal resistance between internal structures and external environment, and decreasing the influence of the external cryogenic environment on the temperatures of camera lens. The method of using electric heating film to heat camera lens was adopted as an active thermal control means. The heat transfer model of the lens in the optical system was built in the WorkBench finite element software with heating power loads, thermal convection loads and thermal radiation loads considered, and steady-state thermal analysis was carried out. It turned out that, the temperature of the camera optical system was controlled in the range of 18℃~22℃ when the heating power of six heating zones was 12、17、22、17、10、13 W, and the thermal control result meted the design requirements.