基于谐衍射理论的0.40~2.50μm宽波段光学系统设计  

Design of 0.40-2.50μm Wide-Band Optical System Based on Harmonic Diffraction Theory

作　　者：王振东 刘欢[1] 陈阳[1] 潘永强[1] 谢万鹏 韩军[1] Wang Zhendong;Liu Huan;Chen Yang;Pan Yongqiang;Xie Wanpeng;Han Jun(School of Armament Science and Technology,Xi’an Technological University,Xi’an 710021,Shaanxi,China)

机构地区：[1]西安工业大学兵器科学与技术学院,陕西西安710021

出　　处：《激光与光电子学进展》2022年第19期310-316,共7页Laser & Optoelectronics Progress

基　　金：陕西省重点研究开发项目(2019ZDLGY16-01)。

摘　　要：基于谐衍射光学元件的负色散和消热差特性,设计了一种工作波段为0.40~2.50μm的宽波段光学成像系统。建立了双层衍射光学元件带宽积分平均衍射效率的数学模型。运用Matlab软件确定衍射元件的最佳设计波长。采用BaF2、AL2O_(3)、AL2O_(3)-E、普通光学玻璃(KZFSN5、SF57)设计了折衍混合5片式光学结构,并通过合理分配光焦度实现了宽波段共光路共焦面集成。实验结果表明,该系统的有效焦距为100 mm,视场角为9.4°,F数为2.8,在-40~60℃范围内可实现无热化。在奈奎斯特频率50 lp/mm处,0.40~0.78μm波段的调制传递函数(MTF)均大于0.6,0.78~2.50μm波段的MTF均大于0.5。相比基于折射透镜的传统宽波段光学系统,该系统具有结构简单、尺寸小且成像质量接近衍射极限的优点。Based on the negative dispersion and heat dissipation characteristics of harmonic diffractive optical elements,a wideband optical imaging system with operating band of 0.40-2.50μm is designed in this paper.The mathematical model of the bandwidth integral average diffraction efficiency of the doublelayer diffractive optical element is established.The optimum design wavelength of diffraction element is determined by Matlab software.BaF2,AL2O_(3),AL2O_(3)-E and ordinary optical glass(KZFSN5,SF57)are used to design the refractive and diffractive hybrid 5-piece optical structure,and the wideband common optical path confocal plane integration is realized by rational distribution of optical focal degree.Experimental results show that,the system has an effective focal length of 100 mm,the field angle of view is 9.4°,and the Fnumber is 2.8.The system achieves no thermo in the range of−40-60℃.At the Nyquist frequency of 50 lp/mm,the modulation transfer function(MTF)of 0.40-0.78μm is greater than 0.6,and the MTF of 0.78-2.50μm is greater than 0.5.Compared with the traditional wideband optical system based on refractive lens,the system has the advantages of simple structure,small size and imaging quality close to the diffraction limit.

关 键 词：光学设计 谐衍射光学元件 双层衍射 宽波段 

分 类 号：O436[机械工程—光学工程]