Preparation of fluoride glass optical preforms and fibers
US5026409A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 3, 1989 |
| Grant date | Jun 25, 1991 |
| Priority date | — |
| Expiry date | Jan 3, 2009 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S65/90
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A preform for preparation of optical fibers is prepared by inserting a rod of a higher index of refraction fluoride glass into the bore of a hollow cylinder of a lower index of refraction fluoride glass fiber. This preform precursor is processed to collapse the hollow cylinder inwardly to form a composite preform having a high-refractive index core and a low-refractive index casing. The preparing of the glasses and processing to a preform are accomplished in a reactive environment that reacts and removes oxygen and hydrogen containing species from the glass, the reactive environment being, for example, Cl.sub.2, CCl.sub.4, SF.sub.6, BF.sub.3, CF.sub.4, or the decomposition products of a liquefied solid fluorocarbon. The preform is then drawn to an optical fiber.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.