GLASSES, METHODS FOR MAKING THEM, AND OPTICAL FIBRES CONTAINING THEM

摘要

GLASSES, METHODS FOR MAKING THEM, AND OPTICAL FIBRES CONTAINING THEM A glass suitable for use in optical fibre cores has a refractive index of 1.540-1.610, Na2O and B2O3 in a molar ratio of 1.05-2:1, 2-12 mole per cent BaO, 40-63 mole per cent SiO2, and 1.5-15 mole per cent ZrO2, the proportion of SiO2 and ZrO2 together not exceeding 65 mole per cent. The glass can be prepared in a highly reduced state by the use of CO and a redox buffering agent. The glass is especially suitable for the production of high numerical aperture wide cored fibres.