Diffusion cover for a motor vehicle headlamp
US4520434A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 28, 1983 |
| Grant date | May 28, 1985 |
| Priority date | — |
| Expiry date | Jul 28, 2003 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF21S41/28
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A diffusion cover for a motor vehicle headlamp comprising upper and lower mutually inclined translucent cover portions are integrally joined together to define therebetween a ridge on an outer surface of the cover and a trough on an inner surface of the cover. In order to obviate or mitigate glare, the trough is disposed above the ridge, the inner surface of the upper cover portion in the region of the trough is of concave form so that the prismatic effect in said region increases in the direction of the trough, the inner surface of the lower cover portion in the region of the trough is of convex form so that the prismatic effect in said region increases in the direction of the trough, and the mutual disposition of the inner and outer surfaces of each cover portion in the respective regions of the ridge and the trough is such that light rays from a reflector of the headlamp which are incident upon the inner surface of the cover in use are not refracted upwardly upon passage through said regions of the upper and lower cover portions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.