Determination of radiative properties of fibrous media by an inverse method—comparison with the Mie theory

In this paper, we present an inverse method based on experimental measurements of bidirectional reflection and transmission (BRDF and BTDF). Silica wool samples are studied by using an optic spectroscopy apparatus comprising a goniometric device and a grating monochromator. The inverse method allows, by means of a least-squares model, the determination of the radiative properties of the medium: albedo, optical thickness and phase function coefficients. A new phase function model taking into account Henyey and Greenstein functions associated with a Lorentz function is used. Our results achieved with the inverse method are compared to those obtained by the Mie theory.