Characteristics of Fiber Laser based Temperature Sensor

In this paper, a fiber laser temperature sensor based on fiber Bragg grating (FBG) is demonstrated. The cavity design of this fiber laser utilizes a linear cavity configuration where both ends are provided by a mirror and the FBG. An erbium-doped fiber amplifier is placed in the middle of the cavity for amplification. The 1560 nm FBG is responsible as a sensor head to detect the temperature change. The laser characteristic with the changing temperature is studied in this work with respect to optical-signal-to-noise ratio (OSNR) and 3-dB bandwidth. It is observed that the OSNR and 3-dB bandwidth of the output laser are 49 dB and 0.076 nm respectively at the temperatures of 30°C, 60 °C and 90°C. Hence, the OSNR and 3-dB bandwidth of the laser are not influenced by the temperature change.