Time-domain analytical solutions of the diffusion equation for photon migration through highly scattering two- and three-layered slabs have been obtained. The effect of the refractive-index mismatch with the external medium is taken into account, and approximate boundary conditions at the interface between the diffusive layers have been considered. A Monte Carlo code for photon migration through a layered slab has also been developed. Comparisons with the results of Monte Carlo simulations showed that the analytical solutions correctly describe the mean path length followed by photons inside each diffusive layer and the shape of the temporal profile of received photons, while discrepancies are observed for the continuous-wave reflectance or transmittance.
© 2002 Optical Society of America
(170.3660) Medical optics and biotechnology : Light propagation in tissues
(170.4580) Medical optics and biotechnology : Optical diagnostics for medicine
(170.5280) Medical optics and biotechnology : Photon migration
(170.6930) Medical optics and biotechnology : Tissue
(170.7050) Medical optics and biotechnology : Turbid media
Fabrizio Martelli, Angelo Sassaroli, Yukio Yamada, and Giovanni Zaccanti, "Analytical approximate solutions of the time-domain diffusion equation in layered slabs," J. Opt. Soc. Am. A 19, 71-80 (2002)