Calibration method and experiment verification for field-integrated imaging spectrometer

The field-integrated snapshot imaging spectrometer, widely used in astronomy, remote sensing, and biomedicine, captures spatial and spectral information simultaneously. Unlike traditional pushbroom systems, these spectrometers require specialized calibration methods due to their unique imaging technique. This paper explores and validates calibration methods tailored for snapshot systems, highlighting their differences from pushbroom methods. Then this paper introduces the working principles of these spectrometers, which utilize a pinhole array, and discusses challenges such as inconsistent dispersion at discrete sampling points, chromatic distortion, and temperature sensitivity. The proposed spectral calibration employs full-spectral monochromatic spots to overcome discrete spectral distribution issues, using pixel coordinate-wavelength fitting to enhance consistency and creating a three-dimensional data cube for real-time spectral recovery. Central wavelength calibration uncertainty is 0.34nm, 6.8% of the standard 5nm spectral resolution, with techniques implemented to counter temperature-induced spectral drift. Finally, a drone airborne experiment was conducted to verify the correctness of the calibration.. This work serves as a technical reference for further development of snapshot imaging spectrometers.