Process for the production of preforms from clear glass for the production of optical fibres

摘要

A process is described for the production of a preform from clear glass for the production of optical fibres for optical communications technology, in which the starting material used for the formation of the preform is highly pure SiO2 in the form of solid glass particles which is produced by the so-called fibre leaching process. The aim is to provide an inexpensive process of this type which is particularly suitable for the production of preforms for monomodal fibres, the fibre type which is the most favourable for long transmission distances in, in particular, postal transmission systems. To this end, a moulding is first produced from the glass material by sintering in a hollow mould, and the moulding is sintered to completion after removal from the hollow mould to give the clear preform. In order to be able to generate the variously doped regions of the fibre to be produced, a hollow mould divided by partitions into hollow sub-moulds which are filled with doped glass material obtained from the starting material is used. <IMAGE>