利用中心波长1064 nm、脉宽12 ns、重复频率5 Hz的NdYAG激光系统，对800 nm、0° Ta2O5/SiO2高反膜进行三种能量台阶数的激光预处理扫描改性；控制扫描速度使辐照脉冲能量重叠70%的峰值能量，辐照模式1-on-1。利用Ti：sapphire激光系统输出800 nm、135 fs超短脉冲激光进行损伤测试。结果表明，纳秒激光表面改性并未提高Ta2O5/SiO2膜飞秒激光诱导损伤阈值，三种台阶数的预处理改性均使Ta2O5/SiO2膜的阈值降低20%以上。说明缺陷(本征的或激光诱导产生的，如带间电子态)对氧化物介质膜的飞秒损伤过程有重要贡献，而这种贡献在样品经过纳秒激光改性后得以体现。

The influence of nanosecond laser surface modification on the femtosecond laser-induced damage of 800 nm Ta2O5/SiO2 dielectric film is investigated in this paper. Surface modification of samples is performed by Raster-scanning with scanning mode of 1-on-1 and scanning velocities timed such that there is a beam overlap at 70% of the peak fluence by 5 Hz-1064 nm-12 ns NdYAG fundamental lasers. Femtosecond laser damage of samples is carried out by 1 kHz-800 nm-135 fs Ti: sapphire laser system with 1-on-1 mode test. The result indicates the femtosecond laser-induced damage thresholds (LIDTs) of all the samples with various modification fluence steps are reduced by about 20%, which seems to be closely related with the contribution of the microscopic electronic defects (native or laser-induced trapping states) in the band gap.