用于近红外光谱仪的平场全息凹面光栅的模拟与设计  

Design of Flat Field Holographic Concave Grating for Near-Infrared Spectrophotometer

作　　者：向贤毅[1] 温志渝[2] 

机构地区：[1]重庆大学光电技术及系统教育部重点实验室,重庆400044 [2]重庆大学微系统研究中心,重庆400044

出　　处：《光谱学与光谱分析》2008年第7期1670-1673,共4页Spectroscopy and Spectral Analysis

基　　金：国家科技部国际合作项目(2006DFA13510);重庆市科技攻关计划项目(CSTC,2006AB2006)资助

摘　　要：针对近红外光谱分析属于微弱信号与多元信息处理的特点，基于全息凹面光栅理论，采用光学设计软件CODEV，从初始结构出发，利用软件强大的全局优化功能，设计出一种用于近红外光谱仪的平场全息凹面光栅，成功地减小了像差，解决了宽光谱、窄谱面展宽的矛盾，并充分利用了光谱信息，是一种高效率的分光光学系统结构。利用CODEV软件，不需要求解复杂的高级像差方程，能对结果进行迅速评价，并可在设计中同时兼顾平场和提高分辨率的要求，极大地提高了工作效率。最后，给出了实例，设计出的全息凹面光栅工作波长范围为900-1700nm、直径Ф=25mm、F／#=1．5，对设计结果分析表明：在宽度为50μm缝光源再现情况下，理论分辨率优于6．3nm。Near-infrared spectrum analysis can be used to determine the nature or test quantitatively some chemical compositions by detecting molecular double frequency and multiple frequency absorption. It has been used in agriculture, biology, petrifaction, foodstuff, medicament, spinning and other fields. Near-infrared spectrophotometer is the main apparatus for near-infrared spectrum analysis, and the grating is the most important part of the apparatus. Based on holographic concave grating theory and optic design software CODE V, a flat field holographic concave grating for near-infrared spectrophotometer was designed from primary structure, which relied on global optimization of the software. The contradiction between wide spectrum bound and limited spectrum extension was resolved, aberrations were reduced successfully, spectrum information was utilized fully, and the optic structure of spectrometer was highly efficient. Using CODE V software, complex high-order aberration equations need not be solved, the result can be evaluated quickly, fiat field and resolving power can be kept in balance, and the work efficiency is also enhanced. A paradigm of flat field holographic concave grating is given, it works between 900 nm to 1 700 nm, the diameter of the concave grating is 25 mm, and F/# is 1.5. The design result was analyzed and evaluated. It was showed that if the slit source, whose width is 50μm, is used to reconstruction, the theoretic resolution capacity is better than 6. 3 nm.

关 键 词：平场全息凹面光栅 近红外 光谱仪 CODE V 

分 类 号：O438.1[机械工程—光学工程]