Analysis of Radiance Error Caused by the Channel Center Wavelength Shift of Imaging Spectrometer

Abstract

Characteristics of radiance spectrum and radiance error distribution after channel center wavelength shift of imaging spectrometers were analyzed in this paper. The results show that shifts of the channel center wavelength can cause shifts of the radiance spectrum, and the shift direction of the two is opposite. The radiance error caused by the channel center wavelength shift is basically distributed near the solar and atmospheric absorption bands. When the center wavelength shifts the same amount towards the positive and negative directions, the absolute value of radiance error is different, which is caused by the asymmetry of spectral absorption region. For 5nm, 10nm and 15nm resolution imaging spectrometers, there is a significant linear relationship between the center wavelength shift and the maximum percent error of radiance. When the center wavelength shift value is less than 10% of the spectral bandwidth, the 10nm imaging spectrometer is most sensitive to the center wavelength shift; when the center wavelength shift is greater than 30%, the 15nm imaging spectrometer is most sensitive to the center wavelength shift.