Study of surface damage morphology and its effect on statistics of nanosecond laser-induced damage growth in fused silica

The growth of rear surface damage in fused silica is governed by complex physical mechanisms and demonstrates statistical behavior, as it depends not only on the parameters of the incident laser but also on the intrinsic characteristics of the damage sites. This study investigates the damage growth characteristics of the rear surface of fused silica subjected to medium-caliber laser irradiation by constructing an initial damage array and employing local fluence mapping techniques. Statistical patterns of damage growth probability and single-shot damage growth coefficients were derived. By analyzing the damage structure, the study analyzes the enhancement effect of crack region size on electric field modulation and calculates the influence of crack zone area on the distribution of damage growth coefficients.