Fiber Ring Laser Sensor for Temperature Measurment Based on Isopropanol Filled SHF in Saganc Loop

In this paper, we proposed a high sensitivity temperature sensor based on isopropanol filled side hole fiber (SHF) in Sagnac loop inside fiber laser. Different from ordinary optical fiber sensors, Sagnac loop is beneficial to long-distance measurement, and the temperature monitoring system based on laser structure has high signal to noise ratio (-30 dB) and narrow linewidth (-0.2 nm). The 10 cm and 15 cm Sagnac rings are compared, and the temperature sensitivity of 0.376 nm/℃ and 0.366 nm/℃ are obtained respectively. It gives great potential for long-distance practical use in many scenarios.