Design of the Cross-Dispersion Echelle Spectrometer

The main objective of the work was to develop a domestic cross-dispersion echelle spectrometer for analyzing samples by the inductively coupled plasma atomic emission spectrometry method. The optical scheme of the spectrometer is based on a horizontal Czerny-Turner scheme using spherical optics. The use of the echelle grating allowed to achieve significantly higher resolving power compared to conventional flat reflective diffraction gratings. A program for modeling the diffraction pattern of the spectrometer has been developed for preliminary calculation of the main parameters of the optical scheme. The final optimization of the scheme with the subsequent analysis of the image quality was carried out in the “Zemax” software. Modeling of spectral resolution for a number of wavelengths was carried out. The comparative analysis showed that the developed scheme demonstrates higher resolution using a larger relative aperture compared to similar devices on the commercial market. A prototype of the echelle spectrometer with a reflective diffraction grating as a dispersing element for the 190–350 nm range was assembled and its main characteristics were experimentally determined. The characteristics of the assembled model of the spectrometer were compared with the spectrometer of “Grand” model, produced by “VMK-Optoelectronics”. As a result of the analysis, the superiority of the specified type of spectrometers realized according to the cross-dispersion scheme was demonstrated.