ON REALISTIC HODELING OF LASER-GENERATED UT,TRASOUND PULSES

The generation of ultrasound pulses with pulsorl lasers has received considerable attention recently. Current applications are to nondestructive evaluation and materials characterization, where it is convenient to have a broad-band source requiring no contact with the sample. The need to make these applications quantitative requires theoretical calculations which allow the use of realistic sample and source properties. This has, until now, dictated approaches which are very computation-intensive. We will describe and illustrate a new formulation which enables such calculations to be accomplished more easily Numerical calculations will be presented to illustrate the efficacy of this approach, with emphasion the effects of finite source dimensions, and on the initial waveform. We also consider the iise of the new approach to investigate siirface-wave generation.