Extra high pressure lamp having a novel electrode structure
US8198816B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 17, 2009 |
| Grant date | Jun 12, 2012 |
| Priority date | — |
| Expiry date | Jun 30, 2030 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J61/0732
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An extra-high pressure mercury lamp includes an arc tube made of quartz glass. The lamp includes an arc tube portion and sealing portions connected to the arc tube portion, and encloses 0.15 mg/mm3 or more of mercury. A pair of electrodes are disposed face to face in the arc tube. Each electrode has a rod portion and a base end portion. The base end portion of each electrode is embedded in one of the sealing portions. One of the pair of electrodes serves as a cathode and includes a head portion, which has a larger diameter than the rod portion. A cylinder portion is connected to a rear end portion of the head portion. The cylinder portion extends in the axis direction of the electrode and surrounds the rod portion. The cylinder portion has an inner surface separated from the rod portion.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.