Optically active glass and optical fiber with reduced photodarkening and method for reducing photodarkening
US8055115B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 5, 2007 |
| Grant date | Nov 8, 2011 |
| Priority date | — |
| Expiry date | Feb 1, 2028 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/2933
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
An optically active glass and an optical fiber comprising such glass, having reduced photodarkening properties are provided. The optically active glass is mainly composed of silica representing from about 50 to 98 mol % of the glass. It also includes at least one active ion, such as a rear-earth ion, which induces a photodarkening effect in optical properties of the glass. Moreover, the glass includes an effective amount of phosphorus oxide providing the photodarkening reducing effect, preferably in an amount of from about 1 to 30 mol %. A method for reducing a photodarkening effect in optical properties of an optically active glass including the step of introducing phosphorus oxide to the glass is also provided.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.