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Main Authors:	Li, Lingxi, Yu, Yue, Borowiec, Joanna, Ramirez-Cuevas, Francisco V, Yang, Danhong, Ghosh, Souvik, Tropea, Cameron, Parkin, Ivan P., Papakonstantinou, Ioannis
Format:	Preprint
Published:	2024
Subjects:	Optics Applied Physics
Online Access:	https://arxiv.org/abs/2411.11887
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author	Li, Lingxi Yu, Yue Borowiec, Joanna Ramirez-Cuevas, Francisco V Yang, Danhong Ghosh, Souvik Tropea, Cameron Parkin, Ivan P. Papakonstantinou, Ioannis
author_facet	Li, Lingxi Yu, Yue Borowiec, Joanna Ramirez-Cuevas, Francisco V Yang, Danhong Ghosh, Souvik Tropea, Cameron Parkin, Ivan P. Papakonstantinou, Ioannis
contents	Photon transport through a diffusing slab can be described by the radiative transfer equation (RTE). When the slab is highly scattering and weakly absorbing, the RTE simplifies to the diffusion equation. In this paper, an inverse diffusion approximation (IDA) method is numerically developed to determine the optical properties (reduced scattering $μ'_s$ and absorption coefficient $μ_a$) of a homogeneous slab using simple reflectance and transmission measurements with a spectrometer. The reflectance and transmission of a diffusing slab with an arbitrary thickness can then be predicted by solving the forward problem by using the calculated $μ'_s$ and $μ_a$. Our method is validated both numerically, by directly comparing with Monte-Carlo simulations, and experimentally, by comparing with measurements on ZnO/PDMS and TiO$_2$/PDMS composite polymer films with varying thicknesses. The IDA method is also applied to distinguish between different types of tissue. Overall, our method could be used to guide the design of radiative cooling reflectors, or lighting and optical display diffusers for applications in medical imaging and other fields.
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institution	arXiv
publishDate	2024
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spellingShingle	Inverse Diffusion Approximation for Extraction of Scattering and Absorption Coefficients in Highly Scattering Media Li, Lingxi Yu, Yue Borowiec, Joanna Ramirez-Cuevas, Francisco V Yang, Danhong Ghosh, Souvik Tropea, Cameron Parkin, Ivan P. Papakonstantinou, Ioannis Optics Applied Physics Photon transport through a diffusing slab can be described by the radiative transfer equation (RTE). When the slab is highly scattering and weakly absorbing, the RTE simplifies to the diffusion equation. In this paper, an inverse diffusion approximation (IDA) method is numerically developed to determine the optical properties (reduced scattering $μ'_s$ and absorption coefficient $μ_a$) of a homogeneous slab using simple reflectance and transmission measurements with a spectrometer. The reflectance and transmission of a diffusing slab with an arbitrary thickness can then be predicted by solving the forward problem by using the calculated $μ'_s$ and $μ_a$. Our method is validated both numerically, by directly comparing with Monte-Carlo simulations, and experimentally, by comparing with measurements on ZnO/PDMS and TiO$_2$/PDMS composite polymer films with varying thicknesses. The IDA method is also applied to distinguish between different types of tissue. Overall, our method could be used to guide the design of radiative cooling reflectors, or lighting and optical display diffusers for applications in medical imaging and other fields.
title	Inverse Diffusion Approximation for Extraction of Scattering and Absorption Coefficients in Highly Scattering Media
topic	Optics Applied Physics
url	https://arxiv.org/abs/2411.11887

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