Abstract
Great progress in the practical application of fiber optic sensors is described. The first topic is a fiber optic gyroscope. Noise sources have been studied thoroughly for an interferometer type. High performance that can meet even a specificationfor aircraft navigation has already been realized. A resonator type has a possibility to shorten the lenth of a sensing fiber coil drastically. A fiber ring laser utilizing fiber Brillouin scattering is investigated as a new type of fiber gyroscope. A fiber optic interferometric sensor has also shown a high sensitivity as an acoustic sensor. Distributed temperature sensor based on temperature dependence of fiber Raman scattering has been developed and is used to monitor the distribution along a high voltage power transmission line. Brilloin scattering can also be applied to the measurement of temperature distribution. Methods to diagnose sensor systems and devices are required, which is also discussed.
