Theoretical Analysis of Frequency Characteristics of Photoacoustic Signal in Liquids

Publisher Website
Google Scholar
Abstract
A Photoacoustic signal as a function of a light modulation frequency is analysed with use of a Fourier transformation and Green's function. The incident laser beam is assumed to be modulated in a δ-function series and to have a Gaussian distribution. The calculated result has a monotonous decrease with increasing frequency under 10 kHz and a resonance peak in the 100 kHz region. It is found that these are caused by decreased photoenergy with increasing frequency and the laser beam profile in the liquids. These results agree well with experimental results found under the same conditions.