对于采用冷光学技术的短波红外透射式成像系统, 由于光学元件及支撑结构的加工、装调温度与实际工作温度差异较大, 几何形状的变化差异将导致光学元件出现位置误差, 甚至受到破坏。本文根据低温红外系统对光机结构的设计要求, 遵循均一性和不调整两个原则设计和加工一套短波红外成像系统的光机结构。在透镜和支撑结构件的配合面上分别加工45°的斜面, 以充分适应光学元件与其支撑结构在温度变化过程的热胀冷缩, 避免了光学元件和支撑结构由于受热变形差异过大而产生的不可恢复性破坏, 最后通过实验验证了该光学支撑方案在80 K的低温下具有良好的成像效果, 本文的研究为今后大温差下的红外光机系统设计提供了较高的参考价值。

For shortwave infrared transmission imaging systems using cold optics, as the difference between fabrication and alignment temperature of optical components and supporting structure with operation temperature is large, variety of changes in geometry for different optical components would lead to position error for optical components, or even be destroyed. Aiming at the requirements of optical machine structural design for low-temperature infrared system, a set of shortwave infrared imaging system is designed and fabricated according to principles of uniformity and non-adjustment. In this pater, 45° slope is designed on the mating surfaces of lens and supporting structure to fully adapt thermal expansion and cold contraction of optical elements and their supporting structure in process of temperature change. At last, it is verified by experiments that this optical supporting scheme has good imaging effect in low temperature condition of 80 K, and this paper provides high reference value for infrared optical machine structural design in large temperature difference.