Method and device for outside plasma deposition of hydroxyl ion-free silica
US5194714A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 5, 1990 |
| Grant date | Mar 16, 1993 |
| Priority date | — |
| Expiry date | Jun 5, 2010 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC03B2207/81
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
Method of outside plasma deposition onto a rod (17,22) of silica substantially free from hydroxyl ions, possibly doped to change its refractive index, by reaction with oxygen of a silicon compound and possibly of doping compounds, in the presence of a gas plasma raised to a very high temperature (16) by induction with the help of a high frequency generator (15). The rod on which the silica deposit is made is kept in a sealed chamber (19) separated from the surrounding atmosphere and supplied by a pipe (20) with atmospheric air that is successively passed through a filter (31), a compressor (32) a cooling means (33), a condensation water drain (35) and a final desiccation by adsorption (36, 38). A device for implementing the method is also claimed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.