Abstract

Since their inception in the 1960s, fiber sensors have been extensively developed for numerous applications, and they are deployed in increasing number every year. Several fiber sensors have had a major impact on important niche markets. The most successful one, the fiber optic gyroscope (FOG), was first commercialized more than 20 years, and more than 100,000 units have been sold to date. Temperature and strain fiber sensors based on fiber Bragg gratings or stimulated Brillouin scattering are used in many smart structures around the world, in particular for fault and fire detection on bridges, elevators, tunnels, and dams. Many other fiber sensors have reached smaller markets, from oxygen sensing in medicine to acoustic-wave detection for undersea surveillance and chemical sensing for a very wide range of applications. In spite of this success, fiber sensors are having difficulty competing with established conventional sensor markets, and they still represent only a small fraction of the world's enormous market. To give them a better edge, several new technologies have been explored in recent years, with the common objective of further improving sensitivity, dynamic range, and stability, as well as reducing size and manufacturing cost.

© 2007 IEEE