Active matrix electroluminescent display device
US6542138B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 11, 2000 |
| Grant date | Apr 1, 2003 |
| Priority date | — |
| Expiry date | Mar 18, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G2360/148
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An active matrix electroluminescent display device in which the drive current through an electroluminescent display element (20) in each pixel (10) in a drive period is controlled by a driving device (22) based on a drive signal applied during a preceding address period and stored as a voltage on an associated storage capacitor (36). In order to counteract the effects of display element ageing, through which the light output for a given drive signal level diminishes over time, the pixel includes electro-optic discharging means (40) coupled to the storage capacitor and responsive to the display element's light output to leak stored charge and to control the integrated light output of the display element in the drive period. For improved control, the discharging means is arranged to rapidly discharge the capacitor at a controlled point in the drive period, upon the drive of the display element falling to a low level. A photoresponsive transistor can conveniently be utilised for this purpose.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.