Reflector system having sharp light cutoff characteristics
US4293901A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 17, 1979 |
| Grant date | Oct 6, 1981 |
| Priority date | — |
| Expiry date | Dec 17, 1999 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S362/804
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A light fixture comprising parabolic reflector segments therein, the lamp being located at the focal point of the segments. One segment has an arc preferably more shallow than the other segment. The window opening is angled preferably at an angle of 60 degrees to the elongate axis of the parabolic segments to provide sharper light cutoff or less spill light from one reflector segment than from the other. A shield positioned parallel to the elongate axis and on the side of the axis within the reflector segment where the cutoff characteristics are the greatest, permits primary reflected light from the lamp, while preventing direct light from the lamp to pass above the shield. The specular underside of the shield enhances light reflection therefrom while the darkened top shield surface blocks secondary reflection above the cutoff angle.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.