Study on Vignetting Simulation Method of Infrared Optical System

Vignetting effect reflects a geometric phenomenon that the radiation illumination which reaches the detector decreases gradually with the increase of off-axis distance. Vignetting effect has become one of the defects of infrared image, and it canpsilat be ignored. So the exact modeling of the vignetting effect is vital for generating an infrared simulation image through optical system. A simulation method of the vignetting effect resulted from infrared optical system is presented. The cause of the vignetting effect is analyzed theoretically by using ray tracing method, and the model of the vignetting effect is established. Then simulation is carried out for the vignetting effect based on image pixel processing. The simulated result is presented. Experiments show that the simulation method of vignetting effect is effective, which is useful for increasing the fidelity of the generated infrared image.