METHOD OF MANUFACTURING SOLID GLASS PREFORMS FROM HOLLOW PREFORMS

摘要

Method of manufacturing solid glass preforms from hollow preforms. Solid glass preforms are obtained by externally heating a preform having a variation of the refractive index over the wall thickness suitable for the end in view, for example, drawing to form an optical fibre, by means of a plasma which is reciprocated past the hollow preform. The plasma gas consists entirely or partly of a molecular gas (N2, O2). The hollow preform is preferably rotated during collapsing.