Apparatus for improving the angle of view in a liquid crystal display
US5150235A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Feb 4, 1991 |
| Grant date | Sep 22, 1992 |
| Priority date | — |
| Expiry date | Feb 4, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F2413/02
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
In a polychromatic liquid crystal display, apparatus and method for improving the off-axis viewing characteristics are described. The angle of view can be expanded by appropriate selection of the thickness and the birefringence parameter of the liquid crystal material as a function of the color of the liquid crystal display pixel. In order to improve further the angle of view, retardation films are used to reduce the angular dependence of the radiation. The retardation films reduce the background light leakage by compensating for the change in retardation of the liquid crystal display at angles other than normal to the display. The reduction in the background light leakage results in improved contrast ratio and chromaticity.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.