Fiber Cavity Ring-Down Refractive Index Sensor

An exploratory study on a novel fiber long-period grating (LPG) cavity ring-down refractive index sensor is conducted. By detecting the ring-down curves at different ambient refractive index levels, the performances of the LPG sensor are investigated. The experimental results demonstrate by using this sensing setup the change of the refractive index in 1.35-1.43 region could be effectively detected.