Beyond Mie Theory: Systematic Computation of Bulk Scattering Parameters based on Microphysical Wave Optics

Light scattering in participating media and translucent materials is typically modeled using the radiative transfer theory. Under the assumption of independent scattering between particles, it utilizes several bulk scattering parameters to statistically characterize light-matter interactions at the macroscale. To calculate these parameters based on microscale material properties, the Lorenz-Mie theory has been considered the gold standard. In this paper, we present a generalized framework capable of systematically and rigorously computing bulk scattering parameters beyond the far-field assumption of Lorenz-Mie theory. Our technique accounts for microscale wave-optics effects such as diffraction and interference as well as interactions between nearby particles. Our framework is general, can be plugged in any renderer supporting Lorenz-Mie scattering, and allows arbitrary packing rates and particles correlation; we demonstrate this generality by computing bulk scattering parameters for a wide range of materials, including anisotropic and correlated media.

Automated summary

This paper presents a generalized framework for computing bulk scattering parameters beyond the far-field assumption of Lorenz-Mie theory, taking into account microscale wave-optics effects and interactions between nearby particles. The framework is versatile, compatible with any renderer supporting Lorenz-Mie scattering, and capable of handling various materials, including anisotropic and correlated media.