All-Fiber Strain Sensor Based on Dual Side V-Grooved Long-Period Fiber Grating

We propose and experimentally demonstrate an all-fiber strain sensor based on dual side V-grooved long-period fiber grating (DSV-LPFG). This fiber structure is achieved by polishing a series of asymmetrical V-shaped grooves on a single mode fiber (SMF), which is fabricated by a high-frequency CO2 laser. The asymmetrically periodic structure enhances the sensitivity of strain and shortens the total length of fiber grating. Experimental results show that the strain sensitivity of the structure reaches 44.6 pm/mu epsilon in the dynamic range of 0-1000 mu epsilon. Meanwhile, the strain sensitivity of the sensor with the different periodic numbers and the offset distance are investigated. Temperature sensitivity of 53 pm/degrees C is obtained, which exhibits a small temperature cross-sensitivity of 1.18 mu epsilon/degrees C. Furthermore, the proposed strain sensor exhibits the advantages of simple structure, convenient fabrication and low cost.

Automated summary

The proposed all-fiber strain sensor based on dual side V-grooved long-period fiber grating (DSV-LPFG) demonstrates high sensitivity, simple structure, and good performance in strain and temperature sensitivity.