Effects of localized CO2 laser damage repair on downstream beam qualities

The diffraction patterns as a function of propagation distance from different parameters of CO₂ laser repair cater are calculated by using a fast-Fourier-transform beam propagation code. The results show that the outer rim of sites leads to laser focusing and causes the more intense downstream modulation, the depth of cater affect the intensity of peaks slightly, and the diameter of cater has no influence on the intensity of peaks. By controlling the rim structure of the mitigation sites, downstream modulation introduced by CO₂ laser repair cater can be declined and decreases the optics damage risk effectively.