Time and polarization resolved ultrasonic measurements using a lensless line-focus transducer

We have developed a transducer which allows the benefits of Line-Focus Beam (LFB) acoustic microscopy to be realized over large areas, using a conventional pulser-receiver. Experimental evidence is presented to show that the transducer is correctly modeled in detail by Green´s function theory, and that all relevant wave speeds can also be predicted using a much simpler geometrical ray model. Data obtained by simply rotating the transducer a fixed distance above the specimen are presented using grey-scale plots which establish the ease with which anisotropy can be revealed. Finally, a grey scale plot of rotational-scan data recast in terms of velocity is shown to demonstrate the simultaneous detection of both surface and pseudo-surface waves in the same crystallographic orientation of a silicon specimen