Mercury and lead free high pressure sodium lamp
US6268696A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 3, 1999 |
| Grant date | Jul 31, 2001 |
| Priority date | — |
| Expiry date | Feb 3, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J61/825
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A long-life, environmentally disposable high pressure sodium lamp comprising: an arc tube capable of withstanding internal wall temperatures of 1250 to 1300.degree. C. and having electrodes sealed therein and being designed for operation at a given wattage; a discharge space within the arc tube and an arc generating and sustaining medium within the discharge space, the medium being mercury-free and containing sodium in an amount of about 0.02 mg to 0.06 mg/watt of designed operation, and xenon at a pressure of 100 to 200 Torr; mounting means supporting the arc tube within a glass outer envelope, the glass outer envelope being lead-free and arsenic-free; and an electrically conductive base closing the outer envelope and containing lead-in wires affixed to the electrodes, the lead-in wires being attached to the base by welding.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.