Oblique-incidence fiber-optic reflectometry for measuring absorption and scattering in turbid media

Oblique-incidence, fiber-optic reflectometry is a simple and accurate method for measuring the absorption and reduced scattering coefficients, μ\sb{a} and μ\sb{s}\sp\prime , of semi-infinite turbid media. Obliquely incident light produces a spatial distribution of diffuse reflectance that is not centered about the point of light entry. The shift in the center of diffuse reflectance is related to the medium's diffusion coefficient, D. We developed a fiber-optic probe to deliver light obliquely and sample the profile of diffuse reflectance. From a relative profile, we measure D, deduce the effective attenuation coefficient, μ\sb{eff}, then calculate μ\sb{a} and μ\sb{s}\sp\prime . This method was verified with Monte Carlo simulations and tested on tissue phantoms. Measurements at 632.8 nm were accurate to within 5% for D and μ\sb{eff}, resulting in 10% and 5% accuracy for μ\sb{a} and μ\sb{s}\sp\prime . In addition, μ\sb{a} and μ\sb{s}\sp\prime spectra were deduced from wavelength-resolved measurements of the diffuse reflectance from a white light source.

Name thesis:degree_name

Master of Science

Level thesis:degree_level

Masters

Discipline thesis:degree_discipline

Engineering

Grantor

Rice University

Year dc:date.issued

1997

Author dc:creator

• Lin, Shao-Pow

Advisor dc:contributor.advisor

• Tittel, Frank K.

• Biomedical engineering
• Radiology
• Optics

Statement dc:rights

• Copyright is held by the author, unless otherwise indicated. Permission to reuse, publish, or reproduce the work beyond the bounds of fair use or other exemptions to copyright law must be obtained from the copyright holder.

Language dc:language.iso

eng

Handle dc:identifier.uri

https://hdl.handle.net/1911/17106

OAI identifier oai:identifier

oai:repository.rice.edu:1911/17106