Pulsed photoacoustic spectroscopy provides information about optical,
thermal and geometrical characteristics of opaque materials. The aim of this
paper is the analysis of the applicability of the finite differences method
to simulate the process by which pulsed photoacoustic signal is generated by
a pulsed heat source, both in time and frequency domains. The present study
is extended to a two-layers absorbing system. This method is free of the
limitations imposed by special cases when the analytical methods are used to
resolve heat diffusion equations. This approach is analyzed through the
temperature and pressure variations in the photoacoustic cell.