FBG-EFPI sensor for large strain measurement with low temperature crosstalk

Abstract A novel optical fiber strain sensor, consisting of a section of fiber Bragg grating cascaded with a Fabry–Perot interferometer is proposed and experimentally demonstrated. The sensing principle relies on the detection of strain-induced changes of the optical intensity. With the assistance of a 3d printed spring, our sensor structure enables a large strain measuring range up to 1.5^107 μ e . the temperature response has also been detected, and the temperature-induced intensity perturbation is less than 0.01dB/ ∘ C from 20 °C to 100 °C. The proposed strain sensor has many advantages such as large measuring range, low temperature cross-sensitivity, simple structure, and ease of fabrication, which make it a competitive candidate for strain measurement under a certain temperature.