Lighting system and lamp with optimal filament placement
US6034473A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 26, 1997 |
| Grant date | Mar 7, 2000 |
| Priority date | — |
| Expiry date | Nov 26, 2017 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF21W2131/406
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A lighting system for projecting a beam of light has a light source and a concave reflector having a central axis. The center of the light source is located at a position other than at the focal point of the reflector, i.e. between the reflector surface and the focal point of the reflector for an ellipsoidal reflector and forward of the focal point for a parabolic reflector. This placement provides a greater light output than is achievable by positioning the light source at the focal point of the reflector. The preferred light source is an improved lamp having an incandescent filament having a central linear helical portion aligned with a central axis of the reflector and a peripheral helix portion around the central portion so as to concentrate the emission of light along and about the central axis of the filament.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.