Metal halide lamp with specific dimension of the discharge tube
US6137229A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 27, 1998 |
| Grant date | Oct 24, 2000 |
| Priority date | — |
| Expiry date | Aug 27, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J61/302
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A metal halide lamp comprises a discharge tube of transparent ceramic in which a discharge metal is sealed, the discharge tube having a main cylindrical portion, ring portions provided at both ends of the main cylindrical portion, and tubular cylindrical portions provided at the ring portions; and a pair of electrodes inside the discharge tube; wherein a wall thickness .alpha. (in mm) of the main cylindrical portion satisfies the relation EQU 0.0023.times.W+0.22.ltoreq..alpha..ltoreq.0.0023.times.W+0.62, and a wall thickness .beta. (in mm) of the ring portion satisfies the relation EQU 0.0094.times.W+0.5.ltoreq..beta..ltoreq.0.0094.times.W+1.5, wherein W is the lamp power expressed in Watt. Alternatively, the discharge tube is air-tightly enclosed in the outer tube; the outer tube is filled with a gas comprising nitrogen gas; and the wall thickness .alpha. (in mm) of the main cylindrical portion satisfies the relation EQU 0.0023.times.W+0.12.ltoreq..alpha..ltoreq.0.0023.times.W+0.62, and the wall thickness .beta. (in mm) of the ring portion satisfies the relation EQU 0.0094.times.W+0.3.ltoreq..beta..ltoreq.0.0094.times.W+1.5, wherein W is the lamp power expressed in Watt. Thus, a m…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.