A Comparison of Methods for Determining Optical Properties of Thin Samples

Area of Science:

• Biomedical Optics
• Materials Science

Background:

• Accurate optical property measurement is crucial for biological tissues and nanomaterials.
• Existing methods may face challenges with physically thin samples.

Purpose of the Study:

• To determine the near-infrared (NIR) optical properties of human retinal pigmented epithelial (RPE) cells and rare earth nanopowders.
• To compare different optical characterization techniques, including Kubelka-Munk, Inverse Adding-Doubling, and Representative Layer Theory (Dahm equation).
• To evaluate the performance of these techniques on thin samples.

Main Methods:

• Utilized a double-integrating sphere setup for optical measurements in the NIR spectrum.
• Applied Kubelka-Munk and Inverse Adding-Doubling methods to derive absorption and scattering coefficients.
• Cultured RPE monolayers from ARPE19 cell line and prepared nanopowder samples of varying thickness.

Main Results:

• Obtained absorption and scattering coefficients for RPE cells and nanopowders.
• Compared results from different theoretical models and experimental techniques.
• Identified limitations of current methods when applied to thin samples.

Conclusions:

• The study provides a comparative analysis of optical property determination for RPE cells and nanopowders.
• Highlights the importance of selecting appropriate techniques for thin sample optical characterization.
• Offers insights into the NIR optical behavior of these materials.