Spatially resolved reflectance from turbid media having a rough surface. Part I: simulations

Area of Science:

• Optical Metrology
• Biophotonics
• Materials Science

Background:

• Spatially resolved reflectance is key for optical property determination.
• Real-world surfaces are often rough, scattering light and complicating measurements.
• Existing methods often assume smooth surfaces, neglecting surface topography effects.

Purpose of the Study:

• To investigate the impact of surface scattering models (Cook-Torrance, Harvey-Shack) on spatially resolved reflectance.
• To analyze how surface roughness affects the calculation of optical properties in turbid media.
• To quantify errors in reduced scattering and absorption coefficients due to unaddressed surface scattering.

Main Methods:

• Utilized Monte Carlo simulations to model light transport through turbid media.
• Incorporated Cook-Torrance and generalized Harvey-Shack surface scattering models.
• Analyzed the resulting spatially resolved reflectance signals and derived optical properties.

Main Results:

• Surface scattering significantly alters spatially resolved reflectance signals.
• Failure to account for surface roughness introduces considerable errors in optical property determination.
• Both investigated surface scattering models demonstrated a notable influence on measurement accuracy.

Conclusions:

• Accurate optical property determination of turbid media requires accounting for surface topography.
• Surface scattering models are crucial for reliable measurements in realistic scenarios.
• Ignoring surface roughness leads to significant inaccuracies in scattering and absorption coefficient calculations.