Fiber-optic sensors for blood flow and respiration rate measurements
1995 (English)Licentiate thesis, comprehensive summary (Other academic)
Optical fibers and fiber-optic sensors have in the last century been subjects for a great interest especially in industry and communication but also in medicine. Optical fibers are used in endoscopes and as light guides for laser surgery. Biomedical sensors using fiberoptics has among other things been developed for analyzes of blood gases, temperature and blood pressure measurement. This thesis describes a method utilizing a fiber-optic sensor for limb blood flow measurement and a new fiber-optic sensor for respiratory rate monitoring.
Venous occlusion plethysmography is a standard method for measuring blood flow in extremities. Today is a mercury strain gauge sensor the most common sensor for this measurement. The mercury strain gauge sensor is very flexible and easy to use, however, there are disadvantages such as temperature drift and long term instability. In addition free mercury from wasted or braken sensor is an environmental problem. We have developed and shown that a fiber-optic sensor that utilizes the microbending principle, can be used for venous occlusion plethysmography in the limb as an alternative to the mercury strain gauge sensor.
The respiratory rate sensor uses an optical fiber that detects the evaporated humidity that departs from the mouth and/or nose at each exhalatfon. The condensed humidity on the fiber end surface substantially alters the coupling ratio of light from the fiber. A number of experiments and computer simulations are determined to evaluate and explain the function of the sensor.
Place, publisher, year, edition, pages
Linköping: Linköpings universitet , 1995. , 44 + 3 papers p.
Linköping Studies in Science and Technology. Thesis, ISSN 0280-7971 ; 480
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:liu:diva-29506Local ID: LiU-Tek-Lic 1995:12ISBN: 91-7871-515-6OAI: oai:DiVA.org:liu-29506DiVA: diva2:250321
1995-05-11, Föreläsningssalen, IMT, Campus US, Linköpings universitet, Linköping, 10:00 (English)