Diffusion of light in turbid media and Kubelka-Munk theory

Walter Schirmacher; Giancarlo Ruocco

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arXiv · 2303.04065

Diffusion of light in turbid media and Kubelka-Munk theory

Walter Schirmacher·Giancarlo Ruocco

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Abstract

We show that the Kubelka-Munk equations for the description of the intensity transfer of light in turbid media are equivalent to a one-dimensional diffusion equation, which is obtained by averaging the three-dimensional diffusion equation over the lateral directions. This enables us to identify uniquely the Kubelka-Munk parameters and derive expressions for diffuse reflection and transmission coefficients including the effect of internal reflections. Without internal reflections we recover the Kubelka-Munk formulas for these coefficients. We show that the Kubelka-Munk equations are the proper radiative-transfer equations for the one-dimensional diffusion problem and comment on previous attempts to derive the Kubelka-Munk equations.

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Walter Schirmacher, Giancarlo Ruocco. 2023-03-07. Diffusion of light in turbid media and Kubelka-Munk theory. https://arxiv.org/abs/2303.04065

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