Half tone display driving circuit for crystal matrix panel and half tone display method thereof
US5038139A · kind A · utility
18Cited by
8References
14Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Aug 18, 1989 |
| Grant date | Aug 6, 1991 |
| Priority date | — |
| Expiry date | Aug 18, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G2310/027
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In a half tone display driving circuit for a liquid crystal matrix panel, a pulse for half tone display is phase modulated so that pulse signals which are out of phase relative to each other are applied to adjacent columns of the liquid crystal matrix panel, or from the phase-modulated pulse a gray scale pulse (tone pulse) is prepared in which the frequency of occurrence of voltage edges is decreased. The dephased pulse signals or the gray scale pulse (tone pulse) is used to prevent a decrease in brightness of display when the liquid crystal matrix panel is driven for half tone display.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.