Method of making an internally-doped tube of transparent glass, in particular for manufacturing rare-earth-doped optical fibers
US4952225A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Oct 14, 1988 |
| Grant date | Aug 28, 1990 |
| Priority date | — |
| Expiry date | Oct 14, 2008 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC03B2201/34
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A mist is formed by an ultrasonic generator (5) from a liquid solution containing a dopant, and the mist is inserted into the tube blank to be doped (4) by means of a flexible pipe (2) in order to deposit microdrops on the inside surface of said tube blank. The flexible pipe is withdrawn progressively so that deposition takes place along the entire length of the tube blank. The deposit is dried and a new layer of glass is deposited thereon. The dopant from the deposit is heat diffused into the glass of the tube blank and of the new layer of glass. The invention is particularly applicable to fabricaitng rare-earth-doped silica preforms for the purpose of drawing optical fibers that can be used to constitute lasers or sensors.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.