High pressure sodium vapor discharge lamp
US5434473A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 4, 1994 |
| Grant date | Jul 18, 1995 |
| Priority date | — |
| Expiry date | Mar 4, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J61/22
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
This invention relates to a high pressure sodium vapor discharge lamp the discharge space of which is enclosed by a ceramic vessel having hermetically sealed ceramic end members with electric lead wires connected with electrodes inside the discharge vessel and the discharge vessel contains sodium, noble gas, mercury in a concentration of 0-5 mg/cm.sup.3 and at least one further metal additive having a vapor pressure not exceeding 7.5 torr at 1000K temperature. The discharge lamp according to the invention is further characterized in that the molar fraction of sodium in the total metal additive exceeds 0.5 and the molar fraction of sodium is greater than four times the molar fraction of mercury.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.