Semiconductor device and driving method thereof
US7365713B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Oct 24, 2002 |
| Grant date | Apr 29, 2008 |
| Priority date | — |
| Expiry date | Jul 3, 2024 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10K59/874
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In a light emitting device, a variation in intensity caused by varying a threshold value of a TFT for supplying a current to a light emitting element for each pixel becomes a burden to an improvement of an image quality of the light emitting device. A voltage equal to the threshold value of a TFT (106) is held in capacitor unit (109). When a video signal is inputted from a source signal line, the voltage held in the capacitor unit is added thereto and a resultant signal is applied to a gate electrode of the TFT (106). Even when a threshold value is varied for each pixel, each threshold value is held in the capacitor unit (109) for each pixel. Thus, the influence of a variation in threshold value can be eliminated. Further, holding of the threshold value is conducted by only the capacitor unit (109) and a charge does not move at writing of a video signal so that a voltage between both electrodes is not changed. Thus, it is not influenced by a variation in capacitance value.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.