Cavity ring-down long-period fibre grating strain sensor

An exploratory study on a novel fibre long-period grating cavity ring-down strain sensor is proposed. By detecting the ring-down time at different strain levels, the performances of the strain sensor are investigated. The experimental results demonstrate that, by using this sensing setup, a high sensitivity of 1.261 ns/με and a minimum detectable strain level of 9 με could be achieved.