Effects of pre-conditioning on 355 nm laser-induced damage growth of fused silica

Laser-induced damage threshold of fused silica under 355 nm laser were measured before and after chemical etching, UV laser conditioning, and the combined processing. The area of damage spots increased with successive pulses irradiation. The results showed that the laser-induced damage threshold of processed samples increased while the area growth rate decreased. Mitigation of damage sites on fused silica by localized CO2 laser treatment was also investigated. The laser-induced damage threshold of treated damage sites was as high as the fused silica substrate by R-on-1 tests. The damage growth of treated sites on fused silica was mitigated effectively.