| 摘要 |
An optical fibre cable for telecommunications comprises a sheath 16 within which there is disposed at least one optical unit having at least one optical fibre 10. The or each optical fibre is protected against the absorption of hydrogen which will cause increased attenuation of the signal being transmitted by the presence in the cable of at least one metallic element of Group III, IV, V or VIII of the periodic system. In one embodiment the or each metallic element is present in a powder which is dispersed within a filler 21 disposed within the sheath. Particular metals referred to are lanthanum or lanthanides, titanium, zirconium, hafnium, vanadium, niobium, tantalum and palladium. <IMAGE> |
