The asymptotic law for the radial distribution of radiance density from an isotropic point source placed in a slab of homogeneous absorbing and scattering material is obtained within the framework of diffusion theory. The exponential shape of the tail of the resulting Green function has been observed but was not theoretically explained until now. We derive formulas for both the steady-state and the time-dependent problems. The theoretical results are verified by comparison with Monte Carlo simulations.
© 2004 Optical Society of America
(000.3860) General : Mathematical methods in physics
(010.1300) Atmospheric and oceanic optics : Atmospheric propagation
(170.3660) Medical optics and biotechnology : Light propagation in tissues
Igor N. Polonsky and Anthony B. Davis, "Lateral photon transport in dense scattering and weakly absorbing media of finite thickness: asymptotic analysis of the space–time Green function," J. Opt. Soc. Am. A 21, 1018-1025 (2004)