Investigation of fused tapering with inner pressurized air for microcapillary-based optical sensor

To fabricate thin-wall and large radius microcapillary-based optical sensor with high sensitivity and Q factor, a fused tapering process with inner pressurized air is modelled. The influence of the fabrication condition on the structural parameters of microcapillary is investigated. A microcapillary with large outer radius of 37.34 mu m and thin wall of 1.52 mu m is realized, and its refractive index sensitivity reaches 1126.67 nm/RIU. This provides the potential to microcapillary-based optical sensor application.