Electrodeless discharge lamp and lighting apparatus using the same
US7719173B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 23, 2006 |
| Grant date | May 18, 2010 |
| Priority date | — |
| Expiry date | Jan 5, 2027 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J65/042
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An electrodeless discharge lamp has a bulb into which a discharge gas and a mercury, which is controlled at a temperature of a coldest spot are filled. A power coupler generates a high frequency electromagnetic field. A ferrule couples the bulb and the power coupler. The bulb is configured as a substantially spherical barrel formed of a transparent material and has an opening. A sealing member is welded to the opening of the barrel having a substantially cylindrical cavity. A protrusion, which becomes the coldest spot when the lamp is lit in a state that the ferrule is disposed upward, is formed at an apex of the bulb. A protruding portion is formed in a vicinity just above the ferrule of the bulb, that is, in a bulb neck portion, so that the bulb neck portion becomes the coldest spot when the lamp is lit in a state that the ferrule is disposed downward. Thereby, a constant optical output is obtained, regardless of a posture of installation of the electrodeless discharge lamp.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.