Dual-Gratings Imaging Spectrometer

Common dispersive-type spectroscopic instruments include prism-type and grating-type, usually using a single dispersive element. The continuous imaging band is always limited by the dispersion angle. When it necessary to image two wavebands with an ultra-spectral resolution that are far apart, difficult due large diffraction To broaden spectral coverage of spectrometer, in this paper, we propose dual-gratings spectrometer independently rotating gratings. In proposed system, very apart wavelength bands can be imaged adjacent areas adjusting angle dual This greatly expands spectrometer. Currently, only application area considered for instrument solar applications. article, present optical system illustrate several advantages new structure, discuss problems caused dual-gratings, which referred as overlap between spectra double offset. We deduced calculation process grating rotation angle, relationship final acquired slit, change gratings offset, MTF upper limit reduction spatial frequency. article also summarizes shortcomings structure studies applicable fields under these shortcomings. At last, simulate compare scheme traditional schemes, conclude has certain practical significance.