Performance Repair Of Small Size Damage Of Laser Components

Laser components are often damaged by intense laser irradiation in high-power laser systems.Improving the Load Capacity of Laser Elements and Ensuring the Normal Operation of High Power Laser System are very significant things.Repairing small size damage of laser element surface,restraining damage growth and improving laser damage resistance of laser element are two main methods to improve the service life of laser element.The main research contents and conclusions are as follows:1.When the fused quartz element is irradiated by intense laser,the driving stress produced by thermal effect causes the material near the damage point to melt and flow to heal the damage point.The critical energy and melting depth of fused quartz repaired by single laser irradiation are simulated and analyzed by using the temperature field distribution formula in fused quartz.2.Based on the theory of small-scale damage repair,the repair experiment of small-scale damage on fused quartz surface was designed.Laser irradiation repair experiments and HF-assisted laser irradiation repair experiments were carried out for damage points with transverse size less than 25?m and longitudinal depth less than 5?m.The results show that 50mJ energy irradiation is the best method for repairing the damaged point after HF-assisted treatment,and the longitudinal depth of the damaged point decreases from 4.93?m to 1.17?m.The laser damage threshold of the repairing point can be restored to over 88%of the undamaged fused quartz base,even exceeding the laser damage threshold of the undamaged fused quartz base.At the same time,there is no obvious change in the light transmittance of fused quartz before and after restoration.3.Pretreatment of laser components by laser pretreatment,ion beam post-treatment and HF chemical treatment can improve the laser damage resistance of laser components.The laser damage threshold of HfO₂ thin films can be increased by 28.4%?@1064 nm?and 33.7%?@532 nm?with no significant change in light transmittance.The laser damage threshold of HfO₂ thin films can be increased by 20.18%with no significant change in light transmittance.HF chemical treatment experiments on fused quartz substrates are carried out.The results show that the laser damage threshold of fused quartz substrate increases first and then decreases with etching time,with a maximum increase of 38%,while the transmittance does not change significantly.