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Photon diffusion coefficient in scattering and absorbing media.

Romain Pierrat·Jean-Jacques Greffet·Rémi Carminati
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Abstract

We present a unified derivation of the photon diffusion coefficient for both steady-state and time-dependent transport in disordered absorbing media. The derivation is based on a modal analysis of the time-dependent radiative transfer equation. This approach confirms that the dynamic diffusion coefficient is given by the random-walk result D = cl(*)/3, where l(*) is the transport mean free path and c is the energy velocity, independent of the level of absorption. It also shows that the diffusion coefficient for steady-state transport, often used in biomedical optics, depends on absorption, in agreement with recent theoretical and experimental works. These two results resolve a recurrent controversy in light propagation and imaging in scattering media.

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AbsorptionAlgorithmsComputer SimulationDiffusionImage Interpretation, Computer-AssistedInformation Storage and RetrievalModels, BiologicalNephelometry and TurbidimetryPhotonsRadiation DosageRadiometryScattering, RadiationTomography, OpticalEvaluation StudyJournal ArticleResearch Support, Non-U.S. Gov't

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Romain Pierrat, Jean-Jacques Greffet, Rémi Carminati. 2006. Photon diffusion coefficient in scattering and absorbing media.. https://doi.org/10.1364/josaa.23.001106

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