Fabrication of Hi-Bi multi-core silica optical fibre preforms from dual-curing resins incorporating nano composites

Additive manufacturing (AM) or three-dimensional (3D) printing stands out for its remarkable ability to manufacture custom-designed preforms for specialty silica optical fibres (SOFs) featuring sophisticated structures and diverse material compositions. Here, a novel scheme for manufacturing preforms for highly birefringent multi-core silica optical fibres (Hi-Bi MC SOFs) is proposed and tested using specially formulated dual-curing resins with AM technologies. These resins, incorporating nano composites (NCs), are ultraviolet (UV) and thermally cured to form fibre preforms in respective AM processes. Sample silica fibre preforms are successfully fabricated with holey cladding (Ti-doped, UV cured), multiple cores (Ge-Ti co-doped, thermally cured) and stress applying parts (SAPs, B-Al co-doped, thermally cured). As confirmed by X-ray diffraction (XRD) tests, these preforms can be consolidated into clear amorphous silica with the required structure and strength, demonstrating the potential of the proposed scheme in developing preforms for specialty fibres with custom-designed structures and materials required for sensing applications.