Process for production of glass preform for optical fiber including consolidating in a furnace with a temperature gradient
US5693115A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 2, 1994 |
| Grant date | Dec 2, 1997 |
| Priority date | — |
| Expiry date | Mar 2, 2014 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC03B37/01446
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
In order to provide an improved process for the production of a glass preform for an optical fiber which includes substantially no bubble formation therein and also has a substantially uniform shape, the present invention provides a process for the production of a glass preform which is at least partially formed from silica. In particular, a body is formed on a rod by depositing fine glass particles thereon, preferably by the vapor phase reactions, and heating the body to vitrify under a reduced atmosphere or a vacuumed atmosphere so that the glass preform is produced. According to this process, the heating includes a first heating step of degassing the body at a first heating temperature, a second heating step of shrinking the body at a second heating temperature which is higher than the first heating temperature and which is lower than a third heating temperature, and a third heating step of vitrifying the shrunken body at the third temperature which corresponds to a vitrification temperature of the fine glass particles so as to produce the glass preform.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.