Simultaneous measurement of strain and temperature by inscribing a paired LPGs on a pre-tapered fiber

We designed a new all-fiber sensor composed of a paired LPGs written consecutively along a standard single-mode fiber by electric arc technique to measure strain and temperature simultaneously. Owing to the dual-LPG structure, transmission spectrum includes two specific resonance wavelengths which exhibit distinct responses to external disturbances, thus allowing to discriminate strain and temperature. Unlike the conventional LPG fabrication techniques, LPGs are written on a pre-tapered fiber to enhance the multi-channel selectivity of the sensor. Resonant wavelengths shift to shorter wavelengths due to increase in strain, however increasing temperature causes a shift to longer wavelengths in transmission spectrum. The experimental results show that the proposed sensor can achieve sensitivity of 12.1 pm/mu epsilon and 17.5 pm/degrees C for strain and temperature, respectively. Proposed sensor exhibits the advantages of simple fabrication, low cost, no splicing joints and useful for applications requiring to monitor more than one parameter due to dual attenuation bandwidth characteristics in its transmission spectrum.

Automated summary

The newly designed all-fiber sensor employs a dual-LPG structure and electric arc technique to measure strain and temperature simultaneously. Experimental results demonstrate high sensitivity and advantages such as simple fabrication, low cost, and no splicing joints.