高分辨率旋转光栅光谱仪的设计

Design of a high-resolution rotating grating spectrometer

针对光栅光谱仪中高分辨率与宽光谱难以同时满足的问题,设计了一款基于旋转光栅的Czerny-Turner(C-T型)光路结构的高分辨率宽光谱拉曼光谱仪,激发波长为532 nm,光谱范围为80~3000cm^(-1),分辨率为1.2cm^(-1)。将光谱范围分为低(80~1450cm^(-1))、中(855~2225cm^(-1))、高(1630~3000cm^(-1))3个波段,以优化中波段为主,对全波段进行了优化。通过微调光栅的旋转角度,确保低、中、高波段均位于CCD的有效像面上。该光谱仪成像系统的点列图、均方根图和调制传递函数图均符合设计要求。

A high-resolution and wide-spectral Raman spectrometer based on a Czerny-Turner(CT)optical configuration with a rotating grating was designed to address the trade-off between resolution and spectral coverage in grating spectrometers.The excitation wavelength was set at 532 nm,with a spectral range of 80~3000cm^(-1) with a resolution of 1.2cm^(-1) The spectral range was divided into three bands:low(80~1450cm^(-1)),medium(855~2225cm^(-1)),and high(1630~3000cm^(-1)).Optimization was primarily focused on the medium band,while considering the entire frequency band.By fine-tuning the rotation angle of the grating,the low,medium,and high bands were all located on the effective image plane of the CCD detector.The point spread function,rootmean-square(RMS)wavefront error,and modulation transfer function(MTF)of the imaging system all met the design requirements.