Quantitative atmospheric turbulence simulating method for laser field imaging

Abstract

The image of space objects by optical field imaging telescope is inevitably affected by atmospheric turbulence. Because of the random variation of atmospheric turbulence, it is difficult to control and simulate atmospheric turbulence quantitatively. In order to quantitatively research and reveal the relationship between intensity of atmospheric turbulence and image quality of laser field imaging, a quantitative controlling and simulating experiment method of intensity of atmospheric turbulence is presented. On the one hand, the atmospheric scintillation effect is researched quantitatively by real-time control and adjustment of laser beam intensity; on the other hand, the atmospheric phase disturbance effect is studied quantitatively by real-time regulating of laser frequency difference. A quantitative numerical controlling and simulating platform for atmospheric turbulence was constructed. On this experimental platform, the effect of phase jitter and scintillation of atmospheric turbulence on image quality of laser field imaging is quantitatively studied. The results show that the image quality decreases seriously and the image contour cannot be identified, when the scintillation index of turbulent light intensity is greater than 0.08 and the laser beam frequency difference is greater than 50Hz. In order to improve the image quality, the effect of atmospheric turbulence should be suppressed in the subsequent image reconstruction algorithm, and imaging experiments should be carried out under weak turbulence conditions as far as possible.