高光通量交叉非对称Czerny-Turner拉曼光谱仪光学系统  

Optical System for Asymmetrical Crossed Czerny-Turner Raman Spectrometer with High Luminous Flux

作　　者：范贤光[1] 汤明[1] 王昕[1] 许英杰[1] 李韦[1] 阙靖 王小东[1] 何坚[1] 

机构地区：[1]厦门大学航空航天学院,福建厦门361005

出　　处：《光学学报》2016年第4期226-235,共10页Acta Optica Sinica

基　　金：国家自然科学基金(21503171);中央高校基本科研业务费项目(20720150091;20720150094);福建省高端装备制造协同创新中心资金

摘　　要：为克服分立式便携拉曼光谱仪光通量低的缺点,设计了一种集拉曼探头光路与分光系统于一体的光学系统。探头光路采用大数值孔径的非球面透镜实现样品的有效激发和信号的高效收集,通过胶合透镜组缩小会聚光路尺寸、消除轴向色差。分光系统基于交叉非对称Czerny-Turner结构,为获得期望的光谱分辨率和光谱范围,建立了分光系统光谱分辨率及光谱范围与交叉非对称Czerny-Turner结构参数的关系。由测得的汞灯谱图可知,分光系统的光谱分辨率优于6 cm^(-1)(0.37 nm),光谱范围为790~950 nm(200~2000 cm^(-1))。将设计的光学系统对CCL4进行测试,实验结果表明在相同积分时间内由这种整体式的光学系统检测到的CCL4光谱谱峰强度是用商业探头通过光纤连接分光系统检测到的近3倍,验证了光学系统设计的合理性。To overcome the low luminous flux in separated portable Raman spectrometer, an optical system embodies the probe of Raman spectrometer and monochromator is designed. An aspherical lens with high numerical aperture is used to obtain the effective excitation of sample and the efficient collection of signal in the optical system of the probe. A cemented lens group is used to minish the size of converging path and eliminate chromatic aberration. The monochromator is based on asymmetrical crossed Czerny-Turner structure. For the purpose of achieving desired spectrum resolution and spectrum range, the relationship between the spectrum resolution and spectrum range of the monochromator and the structural parameters of the asymmetrical crossed Czerny-Turner system is established. According to the tested spectrogram of mercury lamp, the spectrum resolution of the monochromator is better than 6 cm 1 （0.37 nm）, and spectrum range is 790-950 nm （200-2000 cm-l）. A sample of CCL4 is introduced to examine the performance of the optical system, the experimented results demonstrate that the peak intensity of spectrogram of CCL measured by this incorporative optical system is almost three times as high as that using a commercial probe couples to the monochromator, which verifies the rationality of the design of the optical system.

关 键 词：光学设计 拉曼光谱 拉曼光谱仪 探头光路 交叉非对称Czerny-Turner结构 

分 类 号：O436[机械工程—光学工程]