Manufacturing method of single mode optical fiber and single mode optical fiber

摘要

The present invention relates to a method for the manufacture of a single mode optical fiber comprising a light-conductive core portion, an internal cladding portion surrounding said core portion and a jacketing portion surrounding said internal cladding portion, in which the refractive index of the core portion is larger than those of the cladding and jacketing portion areas and in which the refractive indices of the cladding and jacketing portion areas are practically equal.