纳秒激光在K9玻璃中聚焦的损伤形貌研究

详细研究了纳秒激光脉冲在K9玻璃内部产生损伤的形貌特点.整个损伤形貌是前端较大、后端逐渐减小，呈纺锤形.损伤区可分为四种类型的损伤形貌：损伤点轴向的丝状等离子通道、熔化区域、裂纹区域和裂纹末端的折射率变化区域.给出了激光脉冲能量在空间的沉积函数和冲击波膨胀压强的表达式，并根据压强的空间分布特点对相应的损伤形貌进行了分析，理论分析与实验结果相符. 关键词： 激光损伤形貌 移动损伤模型 冲击波 激光能量沉积

Study on the morphology of laser induced damage in K9 glass by focused nanosecond pulse

The characteristics of laser induced damage morphology in the bulk of the K9 glass caused by focused nanosecond laser pulse is analyzed in detail. The damage shape looks like a spindle with a large front-end and its thickness gradually decreases on going to the rear end. According to the experimental results, the damaged range can be divided into four zones, namely the filamentary plasma channel, fractures, the fusion zone and the region of varying refractive index. The function of laser pulse energy deposition in space and the expansion pressure of shock wave are deduced, and the corresponding damage morphology is analyzed based on the spatial distribution of pressure. The theoretical analysis agrees with the experimental results.