利用声学法研究单层氧化硅薄膜在不同激光能量下的损伤情况，建立了激光致薄膜产生的声波采集系统，对其采集到的时域信号进行傅里叶变换，比较和分析薄膜损伤前后声波24~40 kHz高频段的曲线，提取频率特征，并提出用曲线相似函数进行薄膜损伤的识别方法。实验数据结果表明，该方法简单易行，可降低环境噪声的影响，既能实现在线检测，又能准确判别薄膜损伤。

The single oxide films damage at different laser energy values was studied with the photo-acoustic method. The acoustic acquisition was established. The frequency spectrum curves was obtained by the Fourier transform of in-time signals. In the experiment, we compared and analysed the frequency spectrum curves from 24 kHz to 40 kHz between the damaged film and undamaged one. By extracting frequency features and establishing frequency curve similarity function, it was possible to judge whether the optical film was damaged. The experimental result shows that the acoustic frequency method can be easily efficient to judge accurately film damage and it can be also used in online inspection conveniently.