First order design of compact, broadband, high spectral resolution ultraviolet-visible imaging spectrometer.

Abstract

An imaging spectrometer combining an entrance slit, a Fabry-Perot interferometer (FPI) and a plane transmission grating is presented. Each unit of the entrance slit is imaged on a separate column of the detector and different wavelengths are dispersed across different rows of that column. To cover the full spectral range, the FPI needs to scan N steps. For each unit of the entrance slit, one spectrum is obtained at each FPI spacing position and a total of N spectra are sequentially obtained to constitute a high resolution spectrum. The combination of imaging, interferometry and dispersive spectrometry enables the instrument to obtain spatial information and high-resolution spectral information of a broadband source in the ultraviolet-visible spectral region. First-order approximations of system performance are given. The unique design of the optics will make the instrument compact and suitable for high-spectral-resolution broadband ultraviolet-visible spectral imaging.