Preparation of semifinished product for manufacture of optical fibers
US4367013A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 11, 1981 |
| Grant date | Jan 4, 1983 |
| Priority date | — |
| Expiry date | Feb 11, 2001 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S65/16
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A process is described for making a doped-silica ingot useful in the manufacture of optical fibers. At least a silicon compound and a titanium compound are decomposed in the flame of the induction plasma burner in the presence of a determined supply of hydrogen and are reacted with the oxygen contained in the burner feed gas and/or in the vector gas to form SiO.sub.2 and H.sub.2 O against a heat-stable support. As a result silica and titanium oxide are deposited on the support in the form of a homogeneous vitreous mass exhibiting a selected concentration of hydroxyl groups between 10 and 50 parts per million. Fluorine-doped silica is deposited radially in the same way on the resulting ingot. The resulting semifinished product is a cylinder consisting of a titanium-doped silica core, whose TiO.sub.2 concentration by weight is about 0.1 to 8%, covered by a sheath of fluorine-doped silica, whose fluorine concentration is about 0.1 to 3%.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.