Feasibility study of the optical fiber Bragg grating sensors in radiation environment

Abstract

Optical fiber sensors have begun to be used for their superior characteristics to electric devices even in radiation environment. The group has tried to apply them to secure the nuclear power plants. An optical fiber Bragg grating (FBG) sensor is a kind of optical fiber sensor which has been developed rapidly in recent years. FBGs reflect light which fulfill the Bragg condition lambda = 2 n L, where lambda is the wavelength of reflecting light, and n and L are the effective refractive index and length of the modulation period in grating part, respectively. FBGs have various good properties as a sensor, for example, sensitivity to multiparameters, capability of embedding in-line and setting at multiple points along a fiber. In this paper, a result of investigation into applicability of vibration sensing with FBGs in a gamma-ray environment is reported.