激光致声技术的研究

从热弹与烧蚀机制两个方面，讨论了激光超声表面波的产生。通过对点光源激励声表面波的机理进行分析，出线光源激励的表达式。进行了表面波同线光源能量、方向角、位置、长度关系的实验研究。实验结果验证了激光超声表面波理论模型的合理性，证实了线光源产生的表面波具有信号强、方向性好等优点。

Study on Laser Generating Ultrasonic Waves

The generation of surface ultrasonic waves is discussed from both the principles of thermo- elasticity and ablation. The expression for exciting with a laser line source is derived through analyzing the principle of exciting surface ultrasonic waves by a laser point source. The experimental investigation on the relations of the surface acoustic waves with the line source energy, azimuth, position and length is carried out. The experimental results verify the rationality of the theoretical model for laser generated surface ultrasonic waves and demonstrate that the surface ultrasonic waves generated by a line source has the advantages of powerful signal and good directivity.