The influence of laser source on generated surface acoustic waves

A laser generation and optical difference detection method of surface acoustic waves(SAW) is used to study the influence of laser source on SAW.SAW are excited employing a Nd∶YAG laser on sample aluminum plate and detected with an optical difference detection system based on optical beam deflection technique with a 632nm He-Ne laser.The experimental investigation of the influence of the type of laser source and line source energy on laser generated SAW is carried out.Furthermore,the generation of SAW is discussed from the principles of thermoelasticity and ablation.In these two principles,the amplitude of SAW takes a great change.With the increase of the incident power density,the amplitude of SAW changes from linear to nonlinear.These results provide powerful guidance for the theory research of laser generated SAW.