Digital micromirror device and spatial heterodyne spectroscopy combined modulation interference spectroscopy

Abstract Spatial heterodyne spectroscopy (SHS) has advantages of hyperspectral, high luminous flux, and high stability. However, its main performance indexes, such as spectral resolution, bandwidth, dynamic range and signal-to-noise ratio (SNR) are all limited by the performance parameters of the area array detector. In this paper, a digital micromirror device (DMD) is applied to the interference spectroscopy, and DMD and SHS combined modulation interference spectroscopy (DMD-SHS) is proposed. On the basis of retaining advantages of SHS such as high stability and hyperspectral resolution, DMD-SHS uses the linear array detector, eliminating high-performance area-array detector dependence and dramatically reducing the cost of the instrument. It can also improve the instrument’s SNR and dynamic range, and enhance weak signals’ detection capability. DMD-SHS theory is analyzed theoretically and further verified by simulation in this paper. The combined modulation method proposed in the paper can also be applied to other interference spectroscopy, and the related research has important scientific significance and application prospect.