Metal halide arc discharge lamp with means for suppressing convection currents within the outer envelope and methods of operating and constructing same
US4580989A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 13, 1984 |
| Grant date | Apr 8, 1986 |
| Priority date | — |
| Expiry date | Apr 13, 2004 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J61/52
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A metal halide arc discharge lamp having a gaseous fill within the outer envelope and means for suppressing convection currents within such fill; and methods of operating and constructing such lamps. A light-transmissive sleeve or enclosure surrounding the arc tube laterally and about at least one end thereof is so shaped and mounted with respect to the arc tube as to insure that the Rayleigh Number, a quantitative measure of convective flow, in the atmosphere laterally surrounding the arc tube will be less than 5.times.10.sup.4 during operation of the lamp whereby excessive convective heat loss in such lamp will be effectively suppressed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.