Vehicle lamp with shaped envelope interior providing a light-trapping dome
US6093999A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 3, 1998 |
| Grant date | Jul 25, 2000 |
| Priority date | — |
| Expiry date | Apr 3, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01K1/28
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A lamp capsule includes a lamp envelope having a tubular portion and a dome closing one end of the tubular portion, a light source mounted in the lamp envelope on or near its central axis for emitting light when energized by electrical energy and a light attenuating coating over the dome. The dome has a shape that traps light emitted by the light source in the direction of the dome. The dome may be shaped such that a dome angle between a tangent to the interior surface of the dome and the central axis of the lamp envelope is 45.degree. or less. The dome may be shaped as a hyperbolic surface of revolution. The lamp capsule is typically used in a vehicle headlamp and provides low glare.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.