Rapid fiber Bragg grating ( FBG ) strain sensor with reflecting/transmitting filter for acoustic emission detection

摘要

To provide an optical fiber strain sensor device and a strain detection method, for measuring precisely acoustic emission (AE) and for detecting effectively a rapid strain change due to a shock load, an optical fiber strain sensor device includes an fiber Bragg grating (FBG) sensor (6) mounted on an object (15) to be measured, a broadband light source (11) for directing a broadband wavelength light ray to the FBG sensor, and an FBG filter (9) that reflects/transmits a light ray reflected from the FBG sensor, and, using the FBG filter, the optical fiber strain sensor device processes and detects a change in the center wavelength of the light ray by an amplitude change with filter (9) and detectors 12/13. Filter (9) may be replaced by a dielectric multilayer filter.