Research on snapshot infrared computational spectral imaging technology

Infrared imaging spectrometer can provide scene image information and spectral information at the same time, so as to deeply analyze the components and characteristics of the scene target. Due to the low resolution of the existing long-wave infrared imaging spectrometer filter and dispersion devices and the serious attenuation of signal energy, the time-modulated Fourier transform infrared spectrometer has a large volume and a high cost. In this paper, we propose a compact snapshot-type long-wave infrared computational spectral imaging method, which provides a new method for infrared spectral imaging and target recognition technology. Based on the coded aperture snapshot spectral imager (CASSI), we propose an imaging method that shares the main lens with two optical paths. One optical path is mainly composed of a coded mask, a relay lens, an amici prism, and a long-wave infrared detector. Its spatial and spectral resolution is determined by the encoded mask and the dispersive element. The optical system finally obtains an aliased two-dimensional image on the detector. The other optical path uses a long-wave infrared detector to provide high-resolution spatial information. Combining the two paths to obtain high-resolution infrared spectral image information through a compressed sensing reconstruction algorithm. The new spectroscopic imager described in this paper has the advantages of real-time detection, long-distance monitoring, and high sensitivity. It is especially suitable for mobile platforms of unmanned aerial vehicle and NanoSat. Can be widely used in trace gas detection, environmental pollution monitoring, medical diagnosis and military aircraft identification and guidance of anti-missile.