Integrated diffuse reflection spectroscopy and iterative multi-plane optical properties extraction framework for optical property extraction across scattering regimes.

Accurate optical-property extraction in turbid media requires reliable sensing across both near- and far-field scattering regimes, where classical diffuse reflection spectroscopy (DRS) is not equally valid. We present an integrated DRS and iterative multi-plane optical properties extraction (IMOPE) framework for characterizing turbid media across scattering regimes. Seven-plane phase retrieval enabled IMOPE analysis, while camera-based DRS provided an objective method for phase-image segmentation. Experiments were performed using tissue-like phantoms with reduced scattering coefficients of 0.35 - 0.75 mm-1 at 632.8 nm. In the transformed DRS profiles, the geometric correction factor m determined the linearization regime. For m = 0.5, squared-slope coefficients obtained from the standard DRS and the integrated system were 0.20 ± 0.009 and 0.19 ± 0.004, respectively, demonstrating good agreement between systems. In contrast, the m = 1 coefficient was 0.09 ± 0.003, confirming the predicted twofold difference between regimes. These results support an effective-pathlength extension beyond classical diffusion theory and establish a unified framework for quantitative optical-property extraction across scattering regimes.