Process for consolidation of porous preform for optical fiber
US5470369A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 16, 1994 |
| Grant date | Nov 28, 1995 |
| Priority date | — |
| Expiry date | Feb 16, 2014 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC03B37/0146
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
There is provided a process for the consolidation of a porous glass preform for an optical fiber by heating the preform under an increasing pattern of a heating temperature in a vacuum furnace comprising a muffle tube therein characterized in that the increasing pattern is divided into two steps consisting of a first step and a second step with regard to time, and the first step has a pattern in which the heating temperature is increased under a reduced pressure atmosphere and a gas comprising at least an inert gas is supplied to the vacuum furnace under the reduced pressure atmosphere and the second step has a pattern in which the heating temperature is increased under a reduced pressure atmosphere in which a gas comprising a smaller amount of an inert gas than that of the first step is supplied to the vacuum furnace or under a vacuum pressure atmosphere in which no gas is supplied to the vacuum furnace.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.