【摘要】 用自制PZT光声传感器研究了离体猪肾在Nd:YAG倍频脉冲激光作用下产生的光声效应和光声波在其中的传播。随入射激光能量的变化,实验观察到以热膨胀为机理的热弹效应和样品击穿产生的冲击波效应。测得击穿阈值为0.59 GW/cm~2,光声波在猪肾表面传播速度为3162±385米/秒,并观察到信号随距离增加而指数衰减。更多还原

【Abstract】 Using the home-made PZT PA transducer,the PA effects induced by focusingthe Nd:YAG SHG laser radiation(532nm)onto the off-body pig’s kidney and PA wave pro-pagation in the sample surface were examined experimentally.The thermoelastic effect based onthermal expansion and the shockwave effect generated due to sample breakdown were observed,respectively,with the variations of the incident laser power.The breakdown threshold deter-mined is 0.59 GW/cm~2.The shockwave velocity detected in pig’s kidney surface is 3162±385meter/sec.The PA signals decay cxpontially with the increase in distance from illuminated spoton the surface of the pig’s kidney.更多还原