Space-time distortion of laser pulses due to multiple scattering in particulate media.

Based on transport theory, a scattering theory is presented which describes the spatiotemporal distortion of time-dependent laser irradiation in a homogeneous particulate medium as a series expansion in scattering orders in an analytically exact manner. Although applicable to the general case of an arbitrary scattering phase function, the theory is elaborated here for Gaussian forward scattering, where it is the generalization of the theory derived by Tam and Zardecki [Opt. Acta 26, 659 (1979)] for cw irradiation. The individual terms of the series are derived from a generalized sequence of functions which are independent of the specific parameters of a given case and thus, once computed, can be used for an arbitrary case of forward scattering.