Electric lamp having optical interference filter of alternating layers of SiO.sub.2 and Nb.sub.2 O.sub.5 --Ta.sub.2 O.sub.5
US6049169A · kind A · utility
5Cited by
7References
13Claims
0Family size
Assignee
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Key dates
| Filing date | Apr 8, 1998 |
| Grant date | Apr 11, 2000 |
| Priority date | — |
| Expiry date | Apr 8, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J61/40
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Thin film interference filter consists of alternating first and second layers, the first layers being silica, the second layers being a mixture of tantala and niobia. The filter may be used on a high temperature lamp in an inert atmosphere if the niobia in the mixture is less than 40% by weight. For higher percentages a partial pressure of oxygen has been found to prevent blackening of the layers.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.