Homogénéisation et aspects multi-échelles de l'absorption de la lumière en biophotonique

Abstract

Homogenization of absorption The light absorption in tissue optics os usually modeled by the Helmholtz equation with two constant parameters, the scattering coefficient and the absorption coefficient (in regards to hemoglobins, red blood cells RBC, 3D angioarchitectonics). This classic approximation of a constant absorption coefficient ("hemoglobin diluted everywhere") corresponds to the homogenization approach. This chapter describes the limiotations of this hypothesis. the consequences of these limitations are important in all domains of biophotonics and also in all sciences (where the Helmholtz equation are usefil): (i) for the inverse problem, when the optical properties are unknown, and we wan to find them using observed measurements from microscopy to macroscale tomography and, (ii) for the forward problem, when the optical properties are "known"