Fig. 1. Overall structure of the high-altitude spectrometer. (a) 3D modeling; (b) Physical radiometer

Fig. 2. 3D image of front optical module

Fig. 3. Observation view field of the high-

Fig. 4. Front lens optical path design of three dispersion modules altitude spectrometer

Fig. 5. Structure diagram of VNIR dispersion unit lens barrel

Fig. 6. Optical path diagrams of the dispersion unit module. (a) VNIR optical path; (b) SWIR1 optical path; (c) SWIR2 optical path

Fig. 7. Overall diagram of the three dispersion unit module. (a) VNIR module; (b) SWIR1 module; (c) SWIR2 module

Fig. 8. Control process of radiometer temperature control

Fig. 9. Physical map of the heating wire

Fig. 10. Physical map of the TEC

Fig. 11. Temperature control flow chart of spectroscopy module

Fig. 12. Comparison experiment of developed radiometer and SVC. (a) Experiment filed;(b) Reflected radiance; (c) Relative deriation

Fig. 13. Flight experiment of field high-altitude balloon. (a) Experiment filed; (b) Schematic illustration of temperature and altitude; (c) Flying-height of radiometer; (d) Surface-reflected radiance; (e) Module temperature; (f) Detector temperature