Acoustic-based measurements of material absorption coefficients: Relationship between laser pulse duration and stress confinement time

The relationship between laser pulse duration (τ p) and stress confinement time (τ sr) was studied using acoustic-based measurements of material absorption coefficient (μ a). A numerical model was developed to simulate stress signals. Experimental photoacoustic measurements at several values of τ were performed to estimate μ a of water. A numerical deconvolution technique was implemented to overcome the limitation of conventional photoacoustics, resulting in up to a 30% improvement in photoacoustic-based estimates of the sample μ a