The Research Of Spectral Resolution Influencing Factors Of FFT-based Imaging Spectrometer

Spectrum and image are two technical ways for our people to observe the nature. The invention of the FFT-based time modulated imaging spectrometer masterly makes the combination of the object image and the spectrum of the internal component material possible. Due to the high spectral resolution of the FFT-based time modulated imaging spectrometer and the abundant spectral information of the internal elements, there’s much attention paid on it. Also, its application has spread over all aspects of the human society and the development of science and technology. High spectral resolution is the pursuit of the technology of the FFT-based time modulated imaging spectral. But at present, the spectral resolution we can achieve cannot meet the demand of the science and social development.In order to improve spectral resolution of the FFT-based time modulated imaging spectral technology, this paper has studied the factors affecting the spectral resolution. Firstly, the paper introduces the development status and trend of imaging spectral technique at home and abroad, expounds the FFT-based time modulated imaging spectroscopy of the purpose and significance of the study, and it is about the basic working principle of the FFT-based time modulated imaging spectral technology in detail; Then, it focuses on the effects of spectral resolution of the FFT-based time modulated imaging spectral technology and analysis of the relationship between the spectral resolution and four performance parameters, which is analyzed and discussed in detail, then uses the optical design software ZEMAX in modeling and analysis of simulation; based on the research results of this paper, it develops a kind of new FFT-based time modulated imaging spectral technique scheme, which is a improved combination of several angle mirrors and plane mirrors instead the one of an angle mirror and a plane mirror, and it reduces the actual movement track length of the moving mirror but still obtains the same required maximum optical path; Finally, it designs a scheme of spectral resolution of the FFT-based time modulated imaging spectral technology, the scheme uses the model of single mirror FFT-based time modulated imaging spectral technology, that achieves the spectral resolution 10～20nm in imaging wave band 3～5μm, and sets up a experimental platform to verify its rationality.The research results show that the spectral resolution of the FFT-based time modulated imaging spectral technology is a trade-off parameter which is mainly affected by the maximum optical path difference. In addition, there is mutual connection and restriction among the spatial resolution, time resolution, radiation resolution and spectral resolution.