Search for dissertations about: "fibre optical sensors"

Showing result 1 - 5 of 14 swedish dissertations containing the words fibre optical sensors.

  2. 1. Fibre Optic Magnetic Field Sensors Utilizing Iron Garnet Materials

    Author : Hans Sohlström; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; yig; iron garnets; rare earth garnets; magneto-opics; optical waveguide; fibre optical sensors; magnetic field measurement; current measurement;

    Abstract : This thesis deals with the subject of fibre optic magnetic field sensors utilizing iron garnet materials. Such materials exhibit a large Faraday rotation which make them advantageous for application in compact mag­netic field sensors. READ MORE

  4. 2. Fibre-Optic Displacement and Temperature Sensing Using Coupling Based Intensity Modulation and Polarisation Modulation Techniques

    Author : Johan Jason; Hans-Erik Nilsson; Bertil Arvidsson; Werner Daum; Mittuniversitetet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; optical fibre sensor; displacement measurement; temperature measurement; fibre coupling; intensity modulation; birefringence; polarisation; OTDR; side-hole fibre;

    Abstract : Optical fibre sensors are employed in the measurements of a number of different physical properties or for event detection in safety and security systems. In those environments which suffer from electromagnetic disturbance, in harsh environments where electronics cannot survive and in applications in favour of distributed detection, fibre-optic sensors have found natural areas of use. READ MORE

  5. 3. Identifying locally induced loads in hard rock tunnel linings by distributed optical fibre sensors

    Author : August Jansson; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Distributed optical fibre sensors; Structural health monitoring; Tunnel lining experiments;

    Abstract : In an infrastructure system, tunnels enable fast means of transportation in impassable terrain or city areas. However, inspections and maintenance can be expensive due to long down time and, in hard rock tunnels, the complexity of the structure may lead to over designing. READ MORE

  6. 4. Durability of Embedded Fibre Optic Sensors in Composites

    Author : Klas Levin; KTH; []
    Keywords : composites; fibre optic sensor; embedded EFPI sensor; bragg grating sensor; durability. Fatique; impact strain measurement;

    Abstract : This thesis concerns various aspects of the durability offibre optic sensors embedded in composite. Since repair orreplacement of embedded sensors is not generally possible, thefunctional reliability of embedded sensors is one of the mostimportant prerequisites for successful use. READ MORE

  7. 5. Theory and Applications of Coupling Based Intensity Modulated Fibre-Optic Sensors

    Author : Johan Jason; Hans-Erik Nilsson; Bertil Arvidsson; Bernt Sundström; Mittuniversitetet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; fibre-optics; sensor; intensity modulation; coupling; Electrical engineering; electronics and photonics; Elektroteknik; elektronik och fotonik;

    Abstract : Optical fibre sensors can be used to measure a wide variety of properties. In some cases they have replaced conventional electronic sensors due to their possibility of performing measurements in environments suffering from electromagnetic disturbance, or in harsh environments where electronics cannot survive. READ MORE