Strain measurement using a fiber Bragg grating Fabry-Perot sensor

A novel method for high resolution static strain measurement was proposed and demonstrated. This method was based on the combination of two fiber Bragg grating (FBG) and an all_fiber Fabry_Perot sensor (FFPI) formed by the two FBGs. The wavelength shift of the FBGs was used for determining the fringe number of the interferometic signal while the FFPI, and the pseudo_heterodyne was used to carry out high_resolution measurement. The resolution for static strain by the actual measuring is 33×10~(-9)e.