Metal halide lamp having a long lifespan
US6815893B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 29, 2002 |
| Grant date | Nov 9, 2004 |
| Priority date | — |
| Expiry date | Dec 29, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J61/827
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The present invention provides a metal halide lamp having a ceramic arc tube vessel that includes a discharge arc tube member and thin tube members, the discharge arc tube member including taper parts and a main tube part in the middle in a longitudinal direction, the taper parts and the main tube part having a larger outside diameter than an outside diameter of ends of the discharge arc tube in a longitudinal direction, and the thin tube members each being fit to the respective ends of the discharge arc tube, where a minimum curvature radius R is set to be 0.3 mm or more at each transitional area of an external surface between each taper part and a corresponding end of the discharge arc tube.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.