受探测器发展水平的限制, 以中阶梯光栅光谱仪为分光模块的ICP-AES电感耦合等离子体原子发射光谱仪(ICP-AES)难以实现宽波段内多元素的同时测量。本文对现有中阶梯光栅光谱仪进行了改进, 设计出一种适用于ICP-AES多元素同时测量的分波段式中阶梯光栅光谱仪。通过改变棱镜的入射角度, 将系统波长扩展为200~900 nm, 光谱分辨率为25 000, 突破了现有探测器尺寸的限制, 实现了宽波段范围内的多元素快速测量。将中阶梯光栅光谱仪与固态ICP光源组合, 进行了系统波长标定与化学试样测试。实验结果表明: 波长测试误差小于0.01 nm, 满足化学元素精确判读要求; 分波段式中阶梯光栅光谱仪在保持原有仪器性能的前提下, 增宽了仪器的有效光谱探测范围, 为多元素的同时测量提供了有效手段。

Limited by the development of detectors, the Inductively Coupled Plasma Atomic Emission Spectrometry(ICP-AES) based on an echelle spectrograph is difficult to complete the multiple element measurement at a wider spectral coverage. This paper focuses on the improvement of an existing echelle spectrograph. It designs a new wider band echelle spectrograph suitable for ICP-AES to measure multiple elements simultaneously. By changing the incident angle of the prism, the wavelength of system is extented 200-900 nm with a spectral resolution of 25 000, which breaks the limitation of existing detector sizes,and realizes rapid and simultaneous measurement for multiple elements at a wider spectral range.By combination the Echelle spectrograph and a ICP, several specimens are measured and analyzed. Experiments show that the ICP-AES with Echelle spectrograph is available to detect multiple elements within a short time correctly, and the wavelength precision is better than 0.01 nm. The wavelength range, optical spectral resolution and the precision of wavelength calibration of the Echelle spectrograph meet the design needs.