激光预处理技术及其应用

Laser conditioning technology and its applications

回顾了国内在激光预处理技术研究方面取得的进展。综述了基于激光预处理技术提升基频介质膜、磷酸二氢钾/高掺氘磷酸二氢钾(KDP/DKDP)晶体等光学元件抗激光损伤性能的机理、效果和关键技术。针对高功率激光驱动器中关键光学元件激光负载能力的提高,建立了大口径光学元件激光预处理平台,实现了基频介质膜元件的激光预处理工程化作业。比较了纳秒和亚纳秒脉冲宽度激光对DKDP晶体损伤性能的影响。基于亚纳秒激光预处理后,纳秒激光辐照至14.4J/cm2(5ns)尚未出现"本征"损伤的实验结果,提出了用于DKDP晶体的亚纳秒激光预处理方案,并指出亚纳秒激光预处理技术将成为高功率激光三倍频晶体抗激光损伤性能达标的关键技术。

Research progress of laser conditioning technology and its applications in China is reviewed in this pa- per. The physical mechanisms, effects and key techniques of laser conditioning on 1w dielectric coatings and po- tassium dihydrogen phosphate（KDP）and doped deuterium KDP （DKDP） crystals are studied. A laser condition- ing platform for large-aperture optics is constructed to increase the laser damage resistance of critical optics used in high power laser systems. The laser conditioning for large-aperture loJ dielectric coatings is realized on engi- neering working. The influences of laser pulse lengths on the laser damage performance of DKDP crystals are compared. It demonstrates that there no intrinsic damage during nanosecond laser irradiation until 14 J/cm2 （5 ns） can be observed in sub-nanosecond conditioned DKDP crystals, so that the scheme proposed in the paper is verified to be feasibility. Finally, it points out that the sub-nanosecond laser conditioning will be the key technol- ogy to implement the anti-laser damage performance of the high laser harmonic generation crystals.