Ceramic metal halide lamp having medium aspect ratio
US6555962B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 17, 2000 |
| Grant date | Apr 29, 2003 |
| Priority date | — |
| Expiry date | Mar 17, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J61/30
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A metal halide lamp has a ceramic discharge vessel with an inside length L, an inside diameter D, and an aspect ratio L/D of between 3 and 5. The fill gas includes xenon, mercury, sodium halide, and halides of rare earth metals. Hydrogen iodide voltage spikes during start-up are related to product of volume and the cold xenon pressure, which are adjusted to limit the spikes. Voltage crest factor is related to the product of total operating pressure and the square of the inside diameter, which are adjusted to limit the crest factor. The ceramic discharge metal halide (CDM)lamp may have a power rating of 200 W or more and can be used with an existing ballast for a high pressure sodium (HPS) lamp of like power rating.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.