中文摘要：

提出了一种非接触式、全光学激光超声检测的实验方法。利用Nd：YAG脉冲激光器、He-Ne激光器和平衡接收器构建一套基于光束偏转法的光差分检测系统，测量了表面带缺陷Al样品的声表面波（SAWs）。通过实验获得了SAWs经过表面缺陷时产生的反射回波及透射波形的特征，说明了线光源产生的超声波非常适合材料表面缺陷的检测。

英文摘要：

A noncontact all-optical method for laser ultrasound detection is described. The surface acoustic waves（SAWs） were excited by employing a Nd, YAG laser on the sample AI plate with artificial surfacebreaking defects and detected by a kind of optical difference detection system based on the optical beam deflection technique using a He-Ne laser. From the experiment, we attain the characteristics of reflected wave and transmitted wave generated by SAWs interacted with the surface-breaking defects, which show that the SAWs generated by laser line source are potential for the surface-breaking defects.