Illuminated LCD apparatus
US5477422A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 27, 1994 |
| Grant date | Dec 19, 1995 |
| Priority date | — |
| Expiry date | Oct 27, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F1/133615
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A back-lit LCD apparatus comprises a LCD (1), one or more LEDs (3) (or other light sources), and a plate-like light guide (2) behind the LCD (1). An attenuating member (5) is included in front or behind the light guide (5). In the former case the attenuating member (5) is formed as a sheet of reflective material on which is printed a pattern of non-reflective dots for reducing the intensity of light reaching portions of the LCD nearest to the light source. In the latter case the attenuating member (5) is transparent and the dots are either opaque or reflective. The size and frequency of the dots may be varied to adjust the level of attenuation. Also, the pattern of dots may be graduated to provide progressively less attenuation as the distance from the LEDs increases.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.