Determination of three optical properties from subdiffusive spatially resolved reflectance calculations

Area of Science:

• Biomedical Optics
• Photonics
• Materials Science

Background:

• Accurate determination of optical properties is crucial for understanding light-tissue interactions.
• Spatially resolved reflectance (SRR) is a non-invasive technique sensitive to subsurface optical properties.

Purpose of the Study:

• To develop and validate a theoretical method for determining key optical properties from SRR data.
• To identify the reduced scattering coefficient (μs′), absorption coefficient (μa), and phase function parameter (σ).

Main Methods:

• Utilized an analytical solution of the radiative transfer equation to calculate reflectance profiles.
• Employed principal component analysis (PCA) on a large dataset of simulated reflectance profiles.
• Tested the method across a range of μs′ (0.63–4.2 mm⁻¹) and μa (0.002–0.1 mm⁻¹).

Main Results:

• Successfully reconstructed μs′ and μa with low median errors (2.5% and 12%, respectively) even with noisy data.
• Achieved an absolute median error of 0.04 for the phase function parameter σ.
• Demonstrated the robustness of the PCA-based inverse problem solution.

Conclusions:

• The proposed theoretical framework effectively determines optical properties from SRR measurements.
• This method offers a reliable approach for characterizing materials based on their optical response.
• The findings have implications for non-invasive optical diagnostics and material analysis.