编码孔径光谱成像仪中凸面闪耀光栅的研制  

Development of convex blazed grating in coded aperture spectral imager

作　　者：赵雨时 贺文俊[1] 刘智颖[1] 付跃刚[1] Zhao Yushi;He Wenjun;Liu Zhiying;Fu Yuegang(School of Opto-electronic Engineering,Changchun University of Science and Technology,Changchun 130022,China)

机构地区：[1]长春理工大学光电工程学院,吉林长春130022

出　　处：《红外与激光工程》2022年第3期391-400,共10页Infrared and Laser Engineering

基　　金：国家自然科学基金(61805025)。

摘　　要：针对一款基于DMD的光谱维编码Offner光谱成像仪对凸面闪耀光栅的性能要求,提出了一种凸面闪耀光栅的宏观-微观一体化优化设计方法,利用三维偏振光追迹算法有机融合了宏观层面的Offner光学系统设计与微观层面的凸面闪耀光栅槽型设计。介绍了编码孔径Offner光谱成像系统的组成和工作原理,并结合系统的使用要求设计了一款平均衍射效率为85.47%的中波红外凸面闪耀光栅。在此基础上,采用超精密单点金刚石车床成功制备了曲率半径为120 mm、周期为99.945μm、闪耀角为1.178 3°、槽深为1.834μm的凸面闪耀光栅。测试结果表明,在3~5μm光谱范围内,最大衍射效率为93.46%,平均衍射效率为84.29%,与理论设计值较为吻合,验证了凸面闪耀光栅设计方法的有效性。Aiming at the performance requirements of a DMD-based Offner spectral imager encoding in spectral dimension for a convex blazed grating, a macro-micro integrated optimization design method for convex blazed gratings was proposed. The three-dimensional polarization ray tracing algorithm was used to organically integrate the optical design of the Offner system in macro-level and the groove design of the convex blazed grating in micro-level. The composition and working principle of the coded aperture Offner spectral imaging system were introduced, and a MWIR convex blazed grating with an average diffraction efficiency of 85.47% was designed according to the requirements of the system. On this basis, a convex blazed grating with curvature radius of120 mm, grating period of 99.945 μm, blazed angle of 1.178 3°, groove depth of 1.834 μm was successfully fabricated by using an ultra-precision single-point diamond lathe. The test results show that in the spectral range of 3-5 μm, the maximum diffraction efficiency is 93.46% and the average diffraction efficiency is 84.29%, which is in good agreement with the theoretical design value. Thus, the proposed design method of the convex blazed grating is verified to be effective and valuable.

关 键 词：光谱成像 凸面光栅 衍射效率 编码孔径 

分 类 号：O433[机械工程—光学工程]