Design and analysis of a dual-grating spatial heterodyne spectrometer system

Spatial Heterodyne Spectrometer (SHS) is a novel Fourier transform spectroscopy technique characterized by high spectral resolution, high light throughput, and high stability. It is widely used in remote sensing and astronomical observations. In this paper, we designed a dual-grating spatial heterodyne spectrometer, employing a dual-beam interference system and an improved optical system to enhance spectral resolution and detection sensitivity. In simulation experiments, the optical performance of the spectrometer was analyzed through numerical simulations. The results indicate that this design can achieve a theoretical spectral resolution of 1.23 cm^-1 over a broad spectral range of [16043.6, 20755.6] cm⁻¹ ([481.8,623.3]nm). We constructed an experimental prototype of the spectrometer and conducted a series of tests in a laboratory setting, which verified the reliability and accuracy of the simulation studies.