A Complex Fiber Sensor System for Three Parameters Measurement Simultaneously

We proposed and demonstrated a complex sensor, which combined a long period fiber grating and two fiber Bragg gratings. We used the proposed fiber sensor to detect the surrounding temperature, water level and refractive index of an unknown liquid. The measured parameter range of the temperature, water level and refractive index were 2 0-45°C, 40–140 cm 1.335-1.375, respectively. The measured results have linearly trend with high sensitivity.