Mid-wave infrared spatial heterodyne interference imaging spectrometer

摘要

Aiming at the spaceborne detection application of mid-wave infrared interference imaging spectrometer, a temporally and spatially modulated interference imaging spectrometer detection scheme based on spatial heterodyne spectroscopy is presented. With the motion of the satellite platform or push-sweep mechanism, the interference modulation signals of different optical path in the same spatial resolution unit are obtained in time-sharing. After interference data reconstruction and spectral restoration, the spectral signals in each spatial resolution unit are finally obtained. The spectrometer consists of a pre-collimating objective unit, a static interferometer unit, an imaging unit and a focal plane unit, which can obtain three-dimensional data cubes of images and spectra at the same time. The spectrometer has the characteristics of large luminous flux, stable structure, miniaturization and so on. Under the requirement that the mid-wave infrared band is 3.7～4.8μm and the spectral resolution is better than that of 3cm~(-1), taking the characteristic spectrum detection of spaceborne mid-wave infrared typical targets is carried out with F#4 focal plane module as an example, the design process and results of the optical system are given. The results show that the design of the optical system meets the requirements of the detection index, which lays a foundation for the remote sensing application of spaceborne high-resolution mid-wave infrared interference imaging spectroscopy.