FDTD-based Monte Carlo method for the simulation of optical transport in complex scattering media

Scattering particles in nature often have complex structures and shapes, which poses a great challenge to study the optical transport in scattering media. This paper proposes what we believe to be a novel Monte Carlo simulation approach based on the finite-difference time-domain (FDTD), capable of modeling the transmission characteristics of light fields, including intensity and polarization, in complex scattering media composed of asymmetric, polydisperse particles. This method overcomes the limitations of conventional Monte Carlo methods that rely on Mie scattering with spherical particles, which are insufficient for accurately simulating the depolarization characteristics of light fields in anisotropic scattering media composed of complex particles. In order to verify the feasibility of this method, the oil smoke scattering model was established for the oil smoke scattering medium. The approximate consistency between the simulation results of the depolarization characteristics and the experimental measurement results verified the effectiveness of this method in simulating the light field intensity and depolarization characteristics in scattering media composed of complex particles.