A dynamic strain sensor with fiber Bragg gratings

The wavelength demodulation of the measurement signal is one of the key technologies for fiber Bragg grating sensors, especially for the dynamic signal measurement. A Bragg grating dynamic strain sensor taking a long period grating as the linear edgedfilter for demodulating the wavelength signal was developed. The meaasurement system has the advantages of simple structure and good measuring repeatability, and can carry out reltime distortionless measurement, whose dynamic strain range is 0～5000με and the strain resolution reaches 3nε/Hz. The design method of the prob of the fiber grating sensor and the method for gluing the fiber Bragg grating with the strain field are analyzed.The dynamic characteristics of the strain sensor are tested with a PZT.