Highly sensitive strain sensor based on a long-period fiber grating with chain-shaped structure

Yiwei Ma; Xiaoyang Li; Senyu Wang; Yang Yi; Xudong Chen; Shuo Zhang; Shengjia Wang; Tao Geng; Chenguo Tong; Weimin Sun; Libo Yuan

doi:10.1364/AO.404861

Highly sensitive strain sensor based on a long-period fiber grating with chain-shaped structure

Appl Opt. 2020 Nov 20;59(33):10278-10282. doi: 10.1364/AO.404861.

Authors

Yiwei Ma, Xiaoyang Li, Senyu Wang, Yang Yi, Xudong Chen, Shuo Zhang, Shengjia Wang, Tao Geng, Chenguo Tong, Weimin Sun, Libo Yuan

PMID: 33361958
DOI: 10.1364/AO.404861

Abstract

In this paper, a novel chain-shaped long-period fiber grating (CS-LPFG) for strain measurement is investigated and experimentally demonstrated. This structure is achieved by polishing periodic slant planes on a single-mode fiber with a high-frequency CO₂ laser. The chain-shaped structures improved the strain sensitivity of the sensor while shortening the length of the sensing unit. Experimental results show that the strain sensitivity of CS-LPFG is 34.8 pm/µε in the range of 0-650 µε, and the total length of the sensing unit is significantly reduced to 7.5 mm. Meanwhile, the temperature-strain cross talk is 1.6 µε/°C, which is much lower than that of most fiber strain sensors.