Practical birefringent fiber Sagnac ring force sensor

摘要

Abstract: A practical birefringent fiber Sagnac ring force sensor has been demonstrated. The sensor is based on the frequency modulation continuous wave technique and simply consists of a birefringent fiber ring. The intensity and the location of a stress applied to the fiber can be determined simultaneously by detecting the amplitude and the frequency of the beat signal which is produced by two forward-coupled mode beams in the Sagnac ring as a result of the applied stress. Similarly, the strain variation of one section of the fiber ring can also be measured by analyzing the phase shift of this beat signal. The experiments demonstrate that resolutions of 1 meter for distributed stress measurements and 4 microstrains for strain measurements can be obtained with this sensor system. !6