Laser-generated ultrasound: its properties, mechanisms and multifarious applications

TLDR

Laser‑generated ultrasound in solids, produced via thermoelastic, plasma, and constrained surface regimes, is reviewed for its diverse applications from nondestructive testing to candle‑flame parameter determination. The study outlines potential future applications of laser‑generated ultrasound. The paper details the mechanisms of ultrasonic generation in these regimes and discusses experimental investigations, including a CO2‑laser–based mechanism.

Abstract

The laser generation of ultrasound in solids is reviewed with particular emphasis on the application of this unique ultrasonic source. Three regimes for the generation of ultrasound in solids using lasers in the visible near infrared wavelength region exist: thermoelastic, plasma and constrained surface source regimes. The mechanism for ultrasonic generation in each of these regimes is given. Recent experimental investigations into laser-generated ultrasound are also described, including a description of a different mechanism for the generation of ultrasound in solids using a CO2 laser. Finally, the many applications of laser-generated ultrasound are reviewed. These applications range from nondestructive testing to the determination of candle flame parameters. Possible future applications are also outlined.