Furnace for heating glass preform for optical fiber and method for producing glass preform
US4969941A · kind A · utility
39Cited by
1References
10Claims
0Family size
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Key dates
| Filing date | Oct 6, 1988 |
| Grant date | Nov 13, 1990 |
| Priority date | — |
| Expiry date | Oct 6, 2008 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S65/16
- WIPO fieldThermal processes and apparatus
- WIPO sectorMechanical engineering
Abstract
A heating furnace for heating a porous preform made of fine particles of quartz base glass for an optical fiber in an atmosphere comprising a fluorine-containing atmosphere to add fluorine to the preform and to vitrify the preform to produce a glass preform for an optical fiber, which comprises a heater and a muffle tube positioned inside the heater to separate a heating atmosphere from the heater, wherein at least the inner layer of the muffle tube consists of highly pure carbon.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.