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Updated: Jul 9, 2026
08:01
The Diffusion of Passive Tracers in Laminar Shear Flow
Published on: May 1, 2018
Method for measuring the diffusion coefficient of homogeneous and layered media
F Martelli1, A Sassaroli, Y Yamada
1Dipartimento di Fisica dell'Università degli Studi di Firenze and Istituto Nazionale Fisica della Materia, Via Santa Marta 3, 50139 Florence, Italy.
Optics Letters
|December 11, 2007
Summary
A new method measures the diffusion coefficient in various media using time-resolved reflectance. This technique simplifies measurements and reliably identifies layered structures in diffusive materials.
Area of Science:
- Optics and Photonics
- Materials Science
- Biomedical Engineering
Background:
- Accurate measurement of diffusion coefficients is crucial for understanding light transport in scattering media.
- Existing methods for diffusion coefficient retrieval can be complex and time-consuming.
- Characterizing layered diffusive media presents unique challenges for optical measurements.
Purpose of the Study:
- To propose a novel, simplified method for measuring the diffusion coefficient.
- To enable accurate characterization of both homogeneous and layered diffusive media.
- To provide a reliable criterion for assessing the layered structure of samples.
Main Methods:
- Utilized multidistance measurements of time-resolved reflectance.
- Developed a retrieval algorithm based on the logarithm of reflectance ratios at different distances.
- Validated the method for homogeneous and layered diffusive media.
Main Results:
- Successfully retrieved the diffusion coefficient using the proposed method.
- Demonstrated the simplicity and efficiency compared to existing techniques.
- Showcased the method's capability to reliably identify layered structures.
Conclusions:
- The proposed method offers a simpler and reliable approach to measure diffusion coefficients.
- This technique is effective for characterizing homogeneous and layered diffusive media.
- The method provides a valuable tool for optical property assessment in various scientific fields.
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