LAUSR

Abstract We propose a dual-parameter active fiber sensor (DP-AFS) based on a fiber ring laser, which uses a single-mode-two-mode-single-mode fiber interferometer (STS-FI) and a two-mode Fiber Bragg Grating (TMFBG) as the intracavity DP sensing element. The effects of different lateral-offset splicing parameters on the interferometric spectra of the STS-FI are investigated. The excitation ratio of the LP11 mode in the STS-FI is the highest when the lateral-offset distance is 6 μ m , which achieves the best sensing performance. By measuring the output wavelength and intensity of the fiber laser, DP sensing of strain and stress with high linearity is achieved simultaneously. The sensor has a strain sensitivity of − 0 . 0167 dB/ μ e and a stress sensitivity of 7 . 67 × 1 0 − 3 nm/N. The proposed DP-AFS can be applied for reliable and precise measurements of strain and stress simultaneously.