Very high efficacy electrodeless high intensity discharge lamps
US4705987A · kind A · utility
15Cited by
12References
8Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Oct 3, 1985 |
| Grant date | Nov 10, 1987 |
| Priority date | — |
| Expiry date | Oct 3, 2005 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J61/34
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An electrodeless arc lamp comprises an outer jacket hermetically sealing and thermally protecting an arc tube inside which has an upwardly convex bottom center section. The absence of chemically reactive electrode material makes it possible to use metal halides other than iodides. The tube contains chlorides, bromides or a mixture thereof of scandium and sodium in a nearly equimolar relationship in addition to mercury and an inert gas. Good color balance can be obtained at reduced reservoir temperature and with less power loss. Reduction in wall temperature makes it possible to attain longer lamp life.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.