SINGLE MODE DISPERSION-SHIFTED OPTICAL FIBRE COMPRISING AN EXTERNAL REFRACTIVE INDEX RING

摘要

The invention concerns a single mode dispersion-shifted optical fibre comprising: a sheathing with a given index (ns); a fibre core with a dual shape core index profile. The invention is characterised in that the fibre core index profile has an external ring with index (n3) higher than that of the sheathing (ns). The invention ensures a better control of the wavelength value for which the chromatic dispersion is nil, while preserving the other transmission characteristics of known fibres, such as mode diameter, a large effective surface and attenuation.