Apparatus and method for displaying levels of greys on a matrix type display screen
US5157524A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 22, 1989 |
| Grant date | Oct 20, 1992 |
| Priority date | — |
| Expiry date | Sep 22, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G3/2074
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Method for displaying levels of greys on a matrix display screen, such as a chiral smectic phase ferroelectric liquid crystals screen, comprising a cell containing the crystal provided on its walls with two matrix systems of right angle i line conductors and j column conductors, the various pixels of the image being defined by the superimposed crossings of these conductors, wherein each pixel is embodied with the aid of p independent sub-pixels each having its own transmission coefficient, each of which is able to display several states of different basic greys, including black and white, and, on each of the p sub-pixels, one of the states of the preceding greys is displayed by taking account, for each of these, of its own transmission so as to obtain for each pixel via the visual addition of the contributions of each sub-pixel the display of a suitable shade of grey closest to the analog value indicated by the video write signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.