基于全息光学元件的光纤光谱仪的光路设计

基于全息光学理论分析了全息光学元件的高斯成像性质，包括光焦度、成像位置、衍射效率以及作为光纤光谱仪光栅元件的可行性，并以全息光栅的成像理论以及光谱仪工作原理为基础，设计了光谱仪器光学系统的各个参数，通过Zemax软件的仿真、像质评价及优化，得出最终的参数和模拟结果。所使用的全息光栅记录波长为575 nm，记录光束之间的夹角为10，一束为平面波，一束为球面波，焦距40 mm,使用+1级衍射光，光栅孔径为10 mm。光谱仪的工作波长范围为400 nm～800 nm，体积140 mm*30 mm*40 mm，谱面展宽29.1 mm。通过在光学平台上搭建光路，利用已研发完成的电路系统及光谱仪软件，针对汞灯光谱进行了试验，光谱分辨率优于8 nm，测量得到的汞灯光谱与标准汞灯光谱一致，表明了所设计的基于全息元件的光纤光谱仪光学系统是可行的。

Design of optical system for fiber optic spectrometer based on holographic optical elements

Based on the theory of holographic optics, we analyzed the Gaussian imaging properties of holographic optical elements, including the optical focal power, position of imaging and diffraction efficiency, verified its feasibility to be a grating for the spectrometer. Based on the above theory and the spectrometer work principle,we designed the optical system, and through the simulation, image quality evaluation and optimization with Zemax，the final result was got. The parameters of holographic grating were as follows: the recording wavelength was 575nm,the angle between the recording beams (a planar wave beam and a spherical wave beam)was 100, the focal length was 40mm, the used diffracted light was +1 order , the aperture was 10 mm；The parameters of spectrometer were as follows:the range of work wavelength was 400 nm~800 nm, the volume was 140 mm30 mm40 mm,the width of spectrum was 29.1 mm. Finally,we built the light path on the optical platform, used the circuit system and the spectrometer software that were developed completely to collect mercury lamp spectrum. Testing results show the spectral resolution is better than 8 nm，the mercury spectra obtained are the same with the standard one, indicating that the optical system designed based on holographic optics is feasible.