TITLE:
Quantitative Determination of Extinction Coefficients in Highly Scattering Liquids Using SLIPI-1p: Application to Thermally Degraded Shea Butter Oil
AUTHORS:
Anicet Kouabenan Kouakou, Serge Martial Adepo, Amara Kamate, Guy-Oscar Regnima, Thouakesseh Jérémie Zoueu
KEYWORDS:
SLIPI-1p, Extinction Coefficient, Structured Illumination, Scattering Media, Optical Diagnostics
JOURNAL NAME:
Open Journal of Applied Sciences,
Vol.16 No.7,
July
28,
2026
ABSTRACT: Accurate determination of optical properties in highly scattering and absorbing media remains a significant challenge for conventional optical techniques due to the strong contribution of multiple light scattering. In this work, an experimental method based on single-phase Structured Laser Illumination Planar Imaging (SLIPI-1p) is proposed for the reliable extraction of the extinction coefficient in optically dense liquids. The method relies on spatially modulated laser sheet illumination combined with a synchronous detection algorithm to suppress multiply scattered light and isolate the singly scattered component. This approach enables robust estimation of optical attenuation parameters even in strongly turbid media where classical transmission-based measurements become limited. The performance of the method is demonstrated through its application to a series of dense liquid samples consisting of shea butter oil subjected to controlled thermal degradation. Ten samples corresponding to successive heating stages were analyzed at a wavelength of 450 nm. The extracted extinction coefficients exhibit a progressive increase from 0.347 to 0.485 mm−1 across the analyzed samples (E1 - E10), highlighting the sensitivity of the method to monitor the relative evolution of optical properties from the first sampled degradation stage (E1). Statistical analysis shows good repeatability, with a coefficient of variation of approximately 10%, confirming the reliability of the experimental protocol. The results demonstrate that the SLIPI-1p approach provides a non-destructive and accurate tool for quantitative optical characterization of highly scattering media. This method opens promising perspectives for real-time monitoring of complex liquid systems and for applications requiring precise optical diagnostics in optically dense environments.