Key issues of damage resistance of final optics for ICF high power laser facility

摘要

3ω laser damage of fused silica optics is the bottleneck of high power laser systems for ICF. Excellent beam qualityplays an important role in improving the anti-damage capability of final optics system. We have developed a new opticalfield measurement technology based on computational optical imaging. With the high power laser prototype of SGII-UPfacility, damage resistance of final optics was experimentally studied. The near filed of laser beam was measured withhigh resolution to study the effects of modulation and propagation on laser damage. The near field improvement of highpower laser beam are reported and the influence of near filed quality on damage performance of final optics arediscussed. The development of the defect detection techniques of final optics are introduced. Finally, we present thedevelopment perspective of final optics system for ICF laser driver. At present, the damage resistance capability of finaloptics assembly (FOA) is more than 6J/cm2 at normal operation, and we will continue to improve the ability in the nextstep.