Design parameters for dispersion-shifted triangular-profile single-mode fibres

The performance of dispersion-shifted triangular- and step-index-profile fibres is compared. It is predicted that operation near a V-value of half the cutoff value gives a fibre that has low splice loss, low cabling loss and low additional loss due to Rayleigh scattering from the doped core. At this V-value, triangular and step fibres have similar propagation properties. Thus, the lower fabrication loss resulting from the graded core/cladding boundary of the triangular profile fibre is achieved without detriment to any other parameter.