Active matrix liquid crystal display and method of driving the same
US6784863B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 4, 2001 |
| Grant date | Aug 31, 2004 |
| Priority date | — |
| Expiry date | Mar 19, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G2320/0223
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An active matrix liquid crystal display drives liquid crystal by writing through TFTs, etc. a source signal from a signal line drive circuit to display electrodes in display cells on a matrix substrate and applying a common signal supplied from a common signal generator to common electrodes on an opposite substrate, the common signal changing in polarity in each frame. After scanning is completed for scan lines corresponding to one frame, a controller controls the interval between scan periods and the cycle of change in polarity of the common signal so as to provide a non-scan period that is longer than the scan period. The provision of the non-scan period extends the duration in which a specified voltage is retained by the display cell. This reduces the effects of variations in retained voltages caused by parasitic capacitance which develops in reflective electrode structures in which the display electrodes partly overlook scan lines and signal lines. Thus, in frame inversion drive, differences in brightness between the top and bottom of the display screen are reduced, and display quality is improved.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.