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Matching the cold shield with the exit pupil of the fringe-imaging system of long-wave infrared (LWIR) spatial heterodyne spectroscopy (SHS) damages illumination uniformity of the interferogram and affects the fringe contrast, which is a significant parameter for LWIR SHS. The optical models of the fringe-imaging system considering and not considering the pupil matching of the cold shield are built to illustrate the effect on the fringe contrast. Simulations based on the optical design software ASAP are conducted to verify the fringe contrast loss for field-widened LWIR SHS. The result shows that the pupil matching of the cold shield decreases the fringe contrast of LWIR SHS and field-widened LWIR SHS by 0.049% and 0.053%, respectively, and the fringe contrast loss increases with the degree of deviation from the telecentric condition of the fringe-imaging system.

The compressive sampling spectral modulated technique is developed in order to avoid time penalty and promote throughput of spectral imaging system,and a digital-micromirror-device based compressive sampling multispectral imaging system is designed.In the technique based compressive sampling spectral information is sampled below Nyquist-criterion with coded aperture to reduce spectral data greatly.In the experiment,the cubic spatial/spectral data cubes of the 612 nm laser and colored striped fabric are reconstructed from 2-Dimension images obtained from detector that contain spectral information using double shrinkage fast iterative algorithm.The results indicate that a digital-micromirror-device based compressive sampling multispectral imaging system has images with high-throughput and high resolution,can compress the spectral simultaneously,and the compression ratio can reach 31∶1.

Spatial heterodyne spectrometers have been used in multiple scientific studies since their invention and early development. Broadband spatial heterodyne spectrometers also have the advantages of large etendue, high spectral resolving powers, and high data collection rates as traditional spatial heterodyne spectrometer. Basic theory, design and performance parameters, breadboard experiment for a broadband, high-resolution spatial heterodyne spectrometer are reported. The experimental spatial heterodyne spectrometer achieves a design resolution 0.39cm-1. Firstly, it is demonstrated that broadband spatial heterodyne spectrometer have the advantages of wide spectral coverage and high spectral resolving power simultaneously; secondly, the effects of optical defects on the system are discussed; thirdly, Two dimension interference data procession also is mentioned.