HOLLOW OPTICAL FIBRE

摘要

The invention relates to optical fibres provided with cavities in the structure thereof. The inventive optical fibre comprises a central core (1), a first annular area (ra) encompassing said central core (1), a second annular area (rb) encompassing the first annular area (ra) and containing average size cavities (3) whose cross section is strictly ranges between a first specified threshold and a second specified threshold strictly greater than the first threshold, a third annular area (rc) encompassing the second annular area (rb) and containing large size cavities (4) whose cross section is strictly greater than the second threshold. In the cross section of the optical fibre, each beam coming away from the core centre outwards the optical fibre meets at least the average size cavity (3) of the second annular area (rb) or the large size cavity (4) of the third annular area (rc), wherein the mean distance between the external perimeter (Ca) of the second annular area (rb) and the internal perimeter (Cb) of the third annular area (rc) is less than half the mean dimension of the large size cavity (4).