Illuminating device for a display unit
US4425604A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 26, 1982 |
| Grant date | Jan 10, 1984 |
| Priority date | — |
| Expiry date | Nov 26, 2002 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09F2013/145
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An illuminating device for a display unit in which the display panel can be illuminated uniformly under a relatively constant luminous intensity. The illuminating device according to the present invention comprises a display panel, at least one light source and a reflector the inner surface of which is defined by at least two elliptical surfaces. One of two foci of each of the elliptical surfaces is located at the center of the light source and the other of two foci thereof is located on the inner surface of said display panel in order to focus rays of light reflected by the reflector on an area on the display panel away from the light source.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.