Investigation of laser induced damage on K9 glass surface using multi-pulse laser

Experimental study of characteristics of laser induced damage on the K9 glass surface, irradiated by Nd:YAG laser operating at 1.064 μm wavelength and approximately 10 ns pulse duration and 1 Hz repetition rate, have been made. The change law of laser pulse output energy versus the repeat number of laser shots was investigated. Stereo microscope was employed to observe laser induced damage morphology after sigle-shot and multi-shot laser irradiation. The ripple damage on the K9 glass surface could be obviously observed, and the failure surface can be devided into three parts: ablation zone, microcrack zone and brittle fracture zone. After the first shot small damage spots appeared on the K9 glass surface; after multi-shot irradiation, microcracks and damage area increased gradually with t