Light propagation in a two-dimensional medium with large inhomogeneities.

Propagation of a broad beam of light in a two-dimensional absorbing medium with large (compared to the light wavelength) inhomogeneities is considered. Within the small-angle approximation, an exact analytical solution to the radiative transfer equation is found for a phase function that decreases exponentially with the single-scattering angle. Attenuation of the total flux and evolution of the angular distribution of light are analyzed in detail. An accuracy of the small-angle diffusion approximation is estimated.