{"id":{"repo_id":"rice","oai_identifier":"oai:repository.rice.edu:1911/17106"},"canonical_url":"https://search.dev.ndltd.org/etd/rice/oai:repository.rice.edu:1911/17106","repository":{"repo_id":"rice","name":"Rice University","base_url":"https://repository.rice.edu/server/oai/request"},"display":{"title":"Oblique-incidence fiber-optic reflectometry for measuring absorption and scattering in turbid media","abstract":"Oblique-incidence, fiber-optic reflectometry is a simple and accurate method for measuring the absorption and reduced scattering coefficients, $\\mu\\sb{a}$ and $\\mu\\sb{s}\\sp\\prime ,$ 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&apos;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, $\\mu\\sb{eff},$ then calculate $\\mu\\sb{a}$ and $\\mu\\sb{s}\\sp\\prime .$ 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 $\\mu\\sb{eff},$ resulting in 10% and 5% accuracy for $\\mu\\sb{a}$ and $\\mu\\sb{s}\\sp\\prime .$ In addition, $\\mu\\sb{a}$ and $\\mu\\sb{s}\\sp\\prime$ spectra were deduced from wavelength-resolved measurements of the diffuse reflectance from a white light source.","abstract_html":"Oblique-incidence, fiber-optic reflectometry is a simple and accurate method for measuring the absorption and reduced scattering coefficients, <span class=\"etd-inline-math\">&mu;\\sb{a}</span> and <span class=\"etd-inline-math\">&mu;\\sb{s}\\sp\\prime ,</span> 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&amp;apos;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, <span class=\"etd-inline-math\">&mu;\\sb{eff},</span> then calculate <span class=\"etd-inline-math\">&mu;\\sb{a}</span> and <span class=\"etd-inline-math\">&mu;\\sb{s}\\sp\\prime .</span> 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 <span class=\"etd-inline-math\">&mu;\\sb{eff},</span> resulting in 10% and 5% accuracy for <span class=\"etd-inline-math\">&mu;\\sb{a}</span> and <span class=\"etd-inline-math\">&mu;\\sb{s}\\sp\\prime .</span> In addition, <span class=\"etd-inline-math\">&mu;\\sb{a}</span> and <span class=\"etd-inline-math\">&mu;\\sb{s}\\sp\\prime</span> spectra were deduced from wavelength-resolved measurements of the diffuse reflectance from a white light source.","abstract_has_math":true,"creators":["Lin, Shao-Pow"],"institution":"Rice University","degree_name":"Master of Science","degree_level":"Masters","degree_discipline":"Engineering","degree_department":null,"school":null,"contributors":[],"advisors":["Tittel, Frank K."],"committee_chairs":[],"committee_members":[],"year":1997,"date_issued":"1997","date_published":"1997","updated_at":"2026-07-24T04:10:19Z","subjects":["Biomedical engineering","Radiology","Optics"],"languages":["eng"],"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."],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://hdl.handle.net/1911/17106","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Tittel, Frank K."]},{"key":"dc:creator","label":"Author","values":["Lin, Shao-Pow"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2009-06-04T08:24:33Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2009-06-04T08:24:33Z"]},{"key":"dc:date.issued","label":"Date","values":["1997"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Engineering"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Masters"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master of Science"]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["Rice University"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Biomedical engineering","Radiology","Optics"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["eng"]},{"key":"dc:rights","label":"Dc Rights","values":["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."]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["https://hdl.handle.net/1911/17106"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["Oblique-incidence, fiber-optic reflectometry is a simple and accurate method for measuring the absorption and reduced scattering coefficients, $\\mu\\sb{a}$ and $\\mu\\sb{s}\\sp\\prime ,$ 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&apos;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, $\\mu\\sb{eff},$ then calculate $\\mu\\sb{a}$ and $\\mu\\sb{s}\\sp\\prime .$ 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 $\\mu\\sb{eff},$ resulting in 10% and 5% accuracy for $\\mu\\sb{a}$ and $\\mu\\sb{s}\\sp\\prime .$ In addition, $\\mu\\sb{a}$ and $\\mu\\sb{s}\\sp\\prime$ spectra were deduced from wavelength-resolved measurements of the diffuse reflectance from a white light source."]},{"key":"dc:format.mimetype","label":"Dc Format Mimetype","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Oblique-incidence fiber-optic reflectometry for measuring absorption and scattering in turbid media"]}]}],"canonical_facts":{"dc:contributor.advisor":["Tittel, Frank K."],"dc:creator":["Lin, Shao-Pow"],"dc:date.accessioned":["2009-06-04T08:24:33Z"],"dc:date.available":["2009-06-04T08:24:33Z"],"dc:date.issued":["1997"],"dc:description.abstract":["Oblique-incidence, fiber-optic reflectometry is a simple and accurate method for measuring the absorption and reduced scattering coefficients, $\\mu\\sb{a}$ and $\\mu\\sb{s}\\sp\\prime ,$ 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&apos;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, $\\mu\\sb{eff},$ then calculate $\\mu\\sb{a}$ and $\\mu\\sb{s}\\sp\\prime .$ 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 $\\mu\\sb{eff},$ resulting in 10% and 5% accuracy for $\\mu\\sb{a}$ and $\\mu\\sb{s}\\sp\\prime .$ In addition, $\\mu\\sb{a}$ and $\\mu\\sb{s}\\sp\\prime$ spectra were deduced from wavelength-resolved measurements of the diffuse reflectance from a white light source."],"dc:format.mimetype":["application/pdf"],"dc:identifier.uri":["https://hdl.handle.net/1911/17106"],"dc:language.iso":["eng"],"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."],"dc:subject":["Biomedical engineering","Radiology","Optics"],"dc:title":["Oblique-incidence fiber-optic reflectometry for measuring absorption and scattering in turbid media"],"dc:type":["Thesis"],"thesis:degree_discipline":["Engineering"],"thesis:degree_level":["Masters"],"thesis:degree_name":["Master of Science"],"thesis:institution_name":["Rice University"]},"updated_at":"2026-07-24T04:10:19Z"}