光轴稳定探测系统无热化光机结构设计

Design of athermalization optical machine structure for optical axis stability detection system

在星地领域,激光通讯设备的发射光轴和接收光轴的对准度至关重要,而温度变化会导致光学元件和机械结构变形,影响光轴对准度,使系统探测精度降低。针对这一问题,本文设计了一种用于探测的高精度光轴稳定系统,根据宽波段和共轭成像的技术要求,使用具有像传递的离轴反射式开普勒望远系统压缩光束,经过分光镜后分别进入到探测子单元中,并设计了长焦距光轴稳定探测系统以提高探测精度;为校正反射系统的热差,根据光学被动无热化技术利用折射镜组补偿反射镜组的热致像差;设计机械结构并进行有限元分析;对有限元数据进行处理并带回到光学软件中仿真温度变化引起的光轴偏移角度;最后搭建平台进行验证。结果表明:光轴稳定探测系统在-10℃时光轴偏移角度为3.90″,在45℃时光轴偏移角度为4.23″,降低了温度变化对光轴偏移的影响。

The alignment accuracy of the emitting and receiving optical axes of laser communication equip-ment in the satellite ground field is crucial.Temperature fluctuation can cause deformations of optical com-ponents and mechanical structures,affecting the optical axis’alignment and reducing the system’s detection accuracy.We design a high-precision optical axis stability system for detection.First,according to the tech-nical requirements of broadband and conjugate imaging,an off-axis reflective Keplerian telescope system with image transfer was applied to compress the beam.After passing through a beam splitter,the beams entered the detection subunit separately.A long focal length optical axis stability detection system was de-signed to improve detection accuracy.To correct the thermal difference of the reflective system,an optical passive non-thermalization technique was employed using a refractive mirror group to compensate for the thermal-induced aberration of the reflective mirror group.The mechanical structure was designed and subjected to finite element analysis.Finite element data were processed and fed into optical software to simu-late the optical axis deviation angle caused by temperature fluctuation.Finally,experiments were conducted for validation.The results show that the optical axis stability detection system has an optical axis deviation angle of 3.90"at-10℃ and 4.23"at 45℃,reducing the impact of temperature fluctuation on optical axis deviation.