Numerical and experimental study on the ultrasonic displacement field generated by a laser pulse line source

Applying the Fourier transform to the wave equations of elastic medium at its surface a laser pulse line sourceis acted,the integral representations of solutions are obtained.Displacemellt wavforms are ca1culated by using doubleFFT.The calculated results include the displacements of the elastic half space of Aluminum medium,and epicenter andoff-epicenter of an Aluminum plate.The two exciting souxces of thermoelastic and ablating generation are consideredrespectively.The experimeot was made on the Aluminum medium with a Nd:YAG laser and the normal displacementsignals are detected by a laser interferometer.The numerical results are quite in agreement with experiments.