Radiation Transfer in Random Media: Biological Tissues

The Pomraning-Eddington approximation for the transport equation is used to derive a two-flux model for a source-free, anisotropic scattering turbid medium. Relations have been derived between the Kubelka-Munk coefficients K and S and the transport parameters σs, σa and g=<μ> for a linear anisotropic scattering medium. The medium is used as a mismatched boundaries medium and may be illuminated by a collimated incident light. The Kubelka-Munk coefficients K and S are used to calculate the reflectivity R and the transmissivity T of the source-free problem. The problem of collimated source is linked to the solution of the source-free problem. The mathematical approach of the calculation for a single layer could be extended to a multi-layers medium. The calculations are carried out for different tissues in vitro and are compared with calculations by the Galerkin method and P1 approximation