Abstract

For a beam impinging on a scattering medium the diffusion approximation to the radiative transport equation is not valid for analyzing the radiance near the source, especially if the medium scatters strongly with a sharp forward peak. To analyze the radiance, we use the Fokker–Planck approximation to the radiative transport equation. Numerical results show a backscattered ring appearing around the beam center. It also appears in Monte Carlo simulations of the radiative transport equation. This ring is manifested from successive near-forward scattering events, so it requires a directional description. Therefore the diffusion approximation cannot predict this ring.

© 2004 Optical Society of America

Beam propagation in sharply peaked forward scattering media

Arnold D. Kim and Miguel Moscoso
J. Opt. Soc. Am. A 21(5) 797-803 (2004)

Time-resolved ring structure of circularly polarized beams backscattered from forward scattering media

Kevin G. Phillips, Min Xu, S.K. Gayen, and R.R. Alfano
Opt. Express 13(20) 7954-7969 (2005)

Light propagation in biological tissue

Arnold D. Kim and Joseph B. Keller
J. Opt. Soc. Am. A 20(1) 92-98 (2003)

Light propagation in tissues with forward-peaked and large-angle scattering

Pedro González-Rodríguez and Arnold D. Kim
Appl. Opt. 47(14) 2599-2609 (2008)

Light propagation in biological tissues containing an absorbing plate

Arnold D. Kim
Appl. Opt. 43(3) 555-563 (2004)