A time-resolved photoacoustic technique has been applied to the study of dissolved and dispersed absorbers in aqueous systems. The temporal pressure profiles generated from colloidal graphite and glucose solutions were measured, and it was found that the amplitude of the photoacoustic signal of both the glucose and the colloidal graphite solutions increase linearly with concentration and that acoustic signal time delay yields the acoustic velocity. The logarithm of the photoacoustic signal amplitude changes linearly with the time delay, with a slope that is proportional to the product of the acoustic velocity and the optical absorption that can thus be determined.
© 2000 Optical Society of America
[Optical Society of America ]
Yaochun Shen, Zuhong Lu, Stephen Spiers, Hugh A. MacKenzie, Helen S. Ashton, John Hannigan, Scott S. Freeborn, and John Lindberg, "Measurement of the Optical Absorption Coefficient of a Liquid by Use of a Time-Resolved Photoacoustic Technique," Appl. Opt. 39, 4007-4012 (2000)