中长波红外双波段自由曲面棱镜  

Dual-Band Freeform Prism in Middle and Long Wave Infrared Region

作　　者：余俊[1,2] 刘晓天 钮信尚 姜斌斌 焦宏飞[1,2] 张锦龙[1,2] 王占山[1,2] Yu Jun;Liu Xiaotian;Niu Xinshang;Jiang Binbin;Jiao Hongfei;Zhang Jinlong;Wang Zhanshan(Key Laboratory of Advanced Micro-Structured Materials,Ministry of Education,Tongji University,Shanghai 200092,China;Institute of Precision Optical Engineering,School of Physics Science and Engineering,Tongji University,Shanghai 200092,China)

机构地区：[1]同济大学先进微结构材料教育部重点实验室,上海200092 [2]同济大学物理科学与工程学院精密光学工程技术研究所,上海200092

出　　处：《光学学报》2023年第8期278-287,共10页Acta Optica Sinica

基　　金：国家自然科学基金(62105244,61621001)。

摘　　要：为解决传统双波段红外成像系统构型复杂的问题,提出了一种将自由曲面棱镜引入双波段成像系统的一体式构型。基于设计中约束追迹光线角度的低灵敏度优化方法,实现了F数为1、焦距为20 mm、视场角为21.8°×16.4°的双波段(3.7~4.8μm和8.0~12.0μm)红外光学系统。在20 lp/mm空间频率处,系统中波红外波段和长波红外波段内所有视场的调制传递函数(MTF)分别高于0.79和0.67。经公差分析可知,该自由曲面棱镜的制造可采用单点车削机床实现。同时,完成了长波红外自由曲面棱镜的试制。Objective Infrared imaging system has been widely applied in infrared night vision,infrared detection,and infrared guidance.However,the detection accuracy of conventional infrared imaging systems in a single wave band is easily affected by regional terrain,ambient temperature,and target camouflage.If an infrared imaging system can obtain the target information in two infrared wave bands at the same time,the interference information can be easily suppressed during complex environment detection applications.The conventional refraction,reflection or reflector dual-band optical systems are usually designed with two channels or a channel including a spectroscope.The former design configuration contains two independent imaging systems,and the latter design configuration contains a reflective system or a broadband achromatic system.To solve the complex configuration of dual-band infrared imaging system,this paper proposes a dualband freeform prism in the middle and long wave infrared region.Methods The freeform prism is a highly integrated optical system consisting of multiple asymmetric surfaces.The direct optimization design strategy can easily obtain invalid optical path structures.Therefore,a progressive optimization design strategy that gradually complicates the optical path can be adopted.Firstly,the on-axis reflective system can be designed according to the optical parameters.Then,the off-axis reflective system can be designed based on the above rotationally symmetric system.Finally,the media air in the optical path can be substituted by refractive materials.Additionally,the achromatic and thermal aberration corrections of the infrared freeform prism should also be considered.After the freeform prism fabrication,surface adjustment cannot be conducted,so it is necessary to decrease the influence of the fabrication tolerance sensitivity during the optimization design.When the deviation between the incident angle and the refraction angle of the refraction surface is smaller,the optical path change in this region is

关 键 词：光学设计 自由曲面棱镜 红外双波段 公差分析 

分 类 号：O434[机械工程—光学工程]