透明液体中激光致声特性

研究透明液体的特性阻抗、激光声的传播距离和激光焦斑半径对激光声信号的影响.通过实验和数值计算发现,在一定范围内,随着特性阻抗的增加,声波的峰值声压、主频和声能也相应增加;随着激光声传播距离的增加,激光声的主频从急速下降变为相对稳定;在保证光击穿的条件下,选择较大的激光焦斑半径,可提高光声能量转换效率.

Laser Induced Sound in Transparent Liquids

Specific acoustic impedance of transparent liquid, sound transmitting distance of laser induced sound and laser beam waist radius are analyzed. It shows that the peak pressure, dominant frequency and energy of laser induced sound increase as specific acoustic impedance increases. The dominant frequency quickly drops in a short distance and then becomes a constant at a larger distance. Under the condition of optical breakdown, a high ratio of laser to sound energy conversion can be obtained with a large lase...