INDEX-INSENSITIVE CURVATURE SENSOR BASED ON HOLEY FIBER MODAL INTERFEROMETER

摘要

An optical fiber curvature sensor based on holey fiber (HF) modal interferometer is demonstrated experimentally. The sensor is fabricated by a length of 2.4 cm HF which is spliced between two single mode fibers. Different resonant peaks have different curvature characteristics, and the sensitivity of 1.815 nm m~(-1) is achieved in the range of 0-0.905 m~(-1) for the peak around 1504 nm. The sensor is insensitive to the surrounding refractive index, so it is more suitable for index-insensitive wavelength-dependent curvature measurement.