| 摘要 |
<p>Optical fibre elements, such as narrow pass-band filters, dispersion equalisers, and channel dropping filters, are constructed from 2 x 2 single mode optical fibre fused tapered couplers having formed on one side of coupling regions (34, 36, 35) Bragg distributed gratings (37) in the two fibres (30, 31) from which the coupler is constructed. By making the gratings at a point where the fibres remain fused together in side-by-side contact it is ensured that they lie equidistant from the coupling region. <IMAGE></p> |
