Remote Gas Pressure Sensor Based on Fiber Ring Laser Embedded With Fabry–Pérot Interferometer and Sagnac Loop

In this paper, we propose a remote gas pressure sensor based on a fiber ring laser embedded with a Fabry-Pérot (F-P) interferometer and a Sagnac loop. A compact optic-fiber F-P interferometer is inserted in the fiber laser and works as the sensing head for gas pressure detection. A wavelength selective filter based on optic-fiber Sagnac loop is used in the fiber laser. The sensitivity of -9.69 nm/kPa is obtained with a narrow 3-dB bandwidth less than 0.02 nm and high signal-to-noise ratio (SNR) ~45 dB. Moreover, the excellent performance of the gas pressure sensor for remote detection is demonstrated.