Optical time of flight magnetic field sensor with high-V sensing layer

Improvements to a magnetic field sensor based upon an optical time-of-flight effect are proposed in this thesis. This sensor operates by coupling light into a rectangular glass block such that it will circulate around the interior due to total internal reflection at all sides. Through the Faraday effect, the application of a magnetic field alters the reflection angle slightly. After this angular deviation accumulates over many round trips, the total internal reflection condition will be lost at one face and the light will exit. The time this takes indicates the strength of the magnetic field. The improvements explored in this thesis center around decoupling the need for a material with a high Verdet constant and the need for a low-loss material. This is done by forming the sensor from a rectangular core of a low loss material with one side coated with a material possessing a high Verdet constant. These improvements are modeled in MATLAB and indicate a minimum detectable field on the order of a few milliTesla. The applications of this sensor to current sensing are also explored, with emphasis on high-voltage transmission lines --Abstract, page iii