The effect of source backing materials and excitation pulse durations on laser-generated ultrasound waveforms.

J Acoust Soc Am

Department of Medical Physics and Biomedical Engineering, University College London, Malet Place Engineering Building, Gower Street, London, WC1E 6BT, United Kingdom.

Published: May 2023

In this article, it is shown experimentally that a planar laser-generated ultrasound source with a hard reflective backing will generate higher acoustic pressures than a comparable source with an acoustically matched backing when the stress confinement condition is not met. Furthermore, while the source with an acoustically matched backing will have a broader bandwidth when the laser pulse is short enough to ensure stress confinement, the bandwidths of both source types will converge as the laser pulse duration increases beyond stress confinement. The explanation of the results is supported by numerical simulations.

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http://dx.doi.org/10.1121/10.0019306DOI Listing

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