Analysis and Measurement of Stray Light in a Visible and Near-Infrared Imaging Spectrometer

In this paper, the generation mechanism of stray light in a visible and near infrared imaging spectrometer with a spectral range of 400nm to 900nm is analyzed. The optical mechanical model of the instrument was established and its stray light level was simulated. Based on the notch method, a stray light measuring device was built. The veiling glare index of the imaging spectrometer was measured to be 0.84%. The uncertainty of measurement was assessed by GUM method, and the influence of uncertainty components on the measurement results was analyzed. When the confidence probability of the measuring device is 95.45%, the measurement uncertainty of veiling glare index is 0.15%. Finally, a comparison and analysis was made between the simulated values of the veiling glare index and the actual measured ones. This work provides technical support for the further development of high resolution imaging spectrometer.