20-channel airborne spectrometer 8- to 13-mkm range

摘要

Abstract: Construction of compact 20-channel airborne spectrometer 8- 13 mkm range is presented. Spectrometer optical part is based on the only metal optical elements as well as a carrier constructive elements. The result of laboratory testing of the spectrometer sensitivity and accuracy are presented. A possible way for unit sensitivity and accuracy improvement are shown. It has been carried out the analysis of possible ways for development of non-imaging spectrometer for 8-13 mkm spectral range. The selected scheme of spectrometer design is optimal from a point of view of ensuring the minimal error of temperature measurement with desired temperature sensitivity. The basic requirements to each of three spectrometer modules and some important parts were determined. Calibration module - the radiative temperature reproducibility relative error has to be less than 0.2 percent. Optical module - the IR energy dissipation in optical system has to be less than 55 percent, the collective objective area has to be approximately 200 cm$+2$/, the aperture ratio of collective objective should be approximately 1, the error of spectral channel location has to be less than 120 nm. Electronic module - the magnitude of equivalent input noise should be less than 8 nV Hz$+$MIN@1/2$/. The 20-element IR radiation detector on the basis of MCT with detectivity D* approximately 1.2 10$+10$/ cm Hz$+1/2$/ Wt$+$MIN@1$/ and photosensitive elements sizes of 250 $MUL 250 mkm has been used. !10