| 摘要 |
A fused tapered optical fibre directional coupler for use in a polarisation-preserving fibre system has a short stub length (4, 8) of non-polarisation-preserving fibre spliced into each fibre (2, 3, 6, 7) from which the coupler is made. The reduced diameter and tapered portions of the coupler are confined to the stub lengths since it is found that low loss coupling is not achieved if these portions are fabricated in fibre with a polarisation-preserving structure. |
