Growth of laser damage in fused silica and CaF2 under 263 nm laser irradiation

This study examined the growth of the laser-damage performance in optical components under the fourth harmonic of Nd:glass laser irradiation (263 nm). The damage-growth threshold of the optical component was relatively low under 263 nm laser irradiation compared to 351 nm irradiation, owing to the higher energy level of 4\(\omega \) photons, and depended on the material characteristics. The preliminary growth of laser damage in fused silica and CaF₂ under 263 nm laser irradiation is reported in this article. The damage growth coefficients of these two materials were obtained by continuously irradiating the optical components using a 263 nm laser with a pulse width of \(\tau = 5\) ns. The damage growth threshold of fused silica is lower than that of CaF₂ because of differences between the materials. The damage characteristics, including the damage morphology and bulk damage, were analyzed.