High sensitivity Sagnac interferometric strain sensor based polarization maintaining fibre enhanced coupling

Abstract

Abstract A high sensitivity, simple fabrication all‐fibre strain sensor is proposed and demonstrated experimentally. The sensor consists of a section of Panda‐type polarization maintaining fibre (PMF) built into a Sagnac interferometer. The Panda‐type PMF is intentionally spliced to the single‐mode fibre through enhanced fusion splicing to excite high‐order polarized modes. The enhanced fusion splicing characterizes a large magnitude of overlap. The measured strain sensitivity reaches up to 32 pm/με and the strain resolution of 0.63 με has been achieved. The proposed fibre strain sensor characterizing easy fabrication and high sensitivity can be a good candidate in the field of structural health monitoring.

Keywords

• Sagnac interferometers
• strain sensors
• temperature measurement
• fibre optic sensors
• strain measurement
• optical fibre fabrication