Increasing the cladding-to-core ratio (D/d) of low D/d ratio core rods in optical fiber performs
US7836728B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 9, 2007 |
| Grant date | Nov 23, 2010 |
| Priority date | — |
| Expiry date | Aug 4, 2028 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC03B37/014
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
An optical fiber preform is fabricated by inserting a number of core body pieces end-to-end inside a glass cylinder, wherein the pieces may have a cladding-to-core diameter (D/d) ratio within the range of one to four. The cylinder with the inserted core body pieces is mounted vertically on a furnace and heated so that the cylinder becomes elongated and its outside diameter collapses to form a core rod from which core rod sections with D/d ratios greater than five, can be cut. A soot overcladding is deposited on the circumference of a core rod section until the diameter of the deposited soot builds to a determined value. The core rod section with the deposited soot overcladding is consolidated to obtain a finished optical fiber preform. The preform preferably has a D/d ratio of about 15 or more, and an optical fiber may be drawn directly from the preform.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.