Photon diffusion and invariant imbedding

摘要

This paper examines multiple scattering processes from the points of view of the source function of radiative transfer and the emergence probability of photon diffusion. It extends previous results to the case of layered slabs, i.e., inhomogeneous plane-parallel media. It derives equations for basic functions of multiple scattering and photon diffusion and obtains relationships among them. The invariant imbedding method is used to physically and analytically derive initial-value problems for functions which also satisfy integral equations. The initial-value problems are useful for numerically solving direct problems, and for tackling inverse problems of remote sensing.