激光聚焦位置对K9光学玻璃损伤的影响

 利用脉宽为10 ns、波长为1 064 nm的激光脉冲聚焦通过K9玻璃的方法，研究了玻璃的损伤形貌与高强度纳秒激光脉冲聚焦位置的关系。当激光脉冲聚焦在样品中心时，吸收能量随着入射能量的增加呈线性增长，玻璃的破坏范围不断扩大；当激光脉冲聚焦在样品表面时，吸收能量随着入射能量的增加呈先增长而后减小最终趋于平稳，玻璃表面的破坏范围也是先增大而后减小趋于平稳，这主要是由于空气被击穿而吸收大量能量引起的。

Influence of laser focusing position on damage of K9 glass

Focusing the laser (10 ns, 1 064 nm) through K9 glass is used to study the relation between the damage appearance of the glass and the focusing position of the high intensity ns laser pulse. When the laser pulses focus at the sample’s center, the absorbed energy increases with the pulses energy linearly and the area of damage also increases. When the laser pulses focus on the sample’s surface, the absorbed energy increases with the energy increasing at first, then decreases and tends to stabilize, which is the result of the air breakdown with large energy absorption．