Laboratoire de Mecanique Physique, UMR CNRS 5469, Universite Bordeaux 1, 33405 Talence, France.
J Acoust Soc Am. 2010 Jan;127(1):181-5. doi: 10.1121/1.3263612.
The generation of acoustic waves by a line-focused laser pulse in an optically absorptive cylinder is studied experimentally and theoretically. Experiments are performed on a 5 mm diameter NG5 colored glass rod using Nd:yttrium aluminum garnet laser, which delivers 5 ns pulses. The numerical simulation is based on the semi-analytical model of a radially distributed thermoelastic source, which takes into account penetration of laser energy into the bulk of the sample. Good agreement between the experimental and calculated wave forms is observed. Comparison of these wave forms with an auxiliary simulation, which assumes the model of a dipole source located at the cylinder surface, reveals the effect of optical penetration on the shape of the wave form and also on the relative amplitude of bulk and surface waves.
实验和理论研究了线聚焦激光脉冲在光学吸收圆柱体内产生声波的现象。实验在一根 5 毫米直径的 NG5 彩色玻璃棒上进行，使用的是 Nd:yttrium aluminum garnet 激光，可提供 5 ns 脉冲。数值模拟基于径向分布热弹源的半解析模型，该模型考虑了激光能量穿透样品体的情况。观察到实验和计算波形之间的良好一致性。将这些波形与假设位于圆柱体面的偶极子源模型的辅助模拟进行比较，揭示了光学穿透对波形形状以及体波和表面波相对幅度的影响。
