高分辨率中阶梯光栅-棱镜交叉色散光路设计

Optical Design of High-Resolution Echelle-Prism Cross-Dispersion

以宽光谱范围、高分辨率的中阶梯光栅光谱仪为研制目标,介绍了中阶梯光栅的色散特性,阐述了基于它的交叉色散原理,提出了分辨率优先的中阶梯光栅-棱镜交叉色散光路设计方法,包括高分辨率的主色散光路设计、分辨叠级的辅助色散光路设计,及主-辅色散光路联合校验三个递进的环节,并结合商用光谱仪进行了实例设计,仿真和实验表明,当光谱范围为400～900nm时,该分光系统在Hg灯546nm处的分辨率可达51 000,在Na光589nm处的分辨率为44 000。

Aiming at the wide-spectrum high-resolution eehelle spectrometer, the dispersion characteristic of the eehelle grating and the cross-dispersion principle is discussed. And an optical design method of resolution preferential echelle-prism cross-disper- sion is described, including the design of high-resolution main dispersion, the auxiliary dispersion for the separation on the over- lapped orders, and the main-auxiliary dispersion calibration and revision. According to the requirements of commercial spectrom- eter, a design example is reported. The simulation and the experiment results show that when the spectral span is 400-900 nm, the resolution for Hg 546 nm is 51 000, and that for Na 589 nm is 44 000.