Sodium-xenon lamp with improved characteristics at end-of-life
US6498429B1 · kind B1 · utility
1Cited by
7References
16Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Nov 15, 1999 |
| Grant date | Dec 24, 2002 |
| Priority date | — |
| Expiry date | Nov 15, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J61/22
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A mercury-free high pressure sodium vapor lamp is dosed with sodium, xenon and zinc as an elemental metal additive. The addition of the metal additive prevents an undesirable low-voltage operating mode of the sodium-xenon discharge associated with a mercury-free HPS lamp, which otherwise occurs when sodium is no longer available to participate in the arc discharge.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.