Design of Orthogonal Tunable Spatial Heterodyne Spectrometer Based on Prism Dispersion

In our paper, we present a new design for an orthogonal tunable spatial heterodyne spectrometer (SHS) and a method to construct a spatial heterodyne base on the prism. Our design makes the radial plane of the tuned shaft orthogonal to the plane of the folding-path thus one can quickly tune the system to an arbitrary spectral range without additional moving parts. In addition, the Prism-Mirror instead of grating in SHS is used to avoid lateral confinement, which causes the resolving power to be overestimated, in the existing SHS based on gratings.