Math, Technology, and Engineering

Winner: Marcus Allegood, Clemson University
Determining the Optical Properties of Biological Tissue Samples

Wavelength dependent light interaction with biological tissue can be described using scattering and absorption coefficients and the cosine of the average scattering angle (g). Accurately determining these optical properties for different tissue types at specific wavelengths is beneficial for a variety of biomedical applications. The goal of this project was to take a user defined g-value and determine the remaining two parameters for a specified wavelength range. A fully automated computer program and process was developed to collect data for all wavelengths in a timely and accurate manner. LabVIEW was used to write programs to collect raw intensity data from a spectrometer registering tissue sample scattered light intensity in an integrating sphere. For full automation, a single LabVIEW / C program collected the experimental data, computed, and outputted the sample's optical properties. The automated program was tested using a tissue mimicking phantom and determination of the absorption and scattering coefficients showed excellent agreement with theory. Future work and the final phase of testing will entail examining actual biological tissue with known optical properties to check for accuracy before proceeding to utilize the system for its intended purpose of generating data for light-tissue interaction algorithm development.