Effect of solar stray light on imaging quality of infrared detection system

The solar stray light will seriously affect the imaging quality of the infrared detection system. The traditional point source transmittance (PSF) index is difficult to evaluate the image degradation of the detection system due to stray light. In this paper, a stray light simulation is performed firstly for a given infrared detection system, and the irradiance distribution of solar stray light on the surface of the detector with different incident angles are obtained. Then a simulation model of the detection system is established based on the physical conversion process of the infrared detection system. By combining this simulation model with the light distribution, the spatial noise of the detection system with solar stray light can be calculated quantitatively, and the image degradation due to solar stray light can be quantitatively evaluated.