Pixel current driver for organic light emitting diode displays
US7414600B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 11, 2005 |
| Grant date | Aug 19, 2008 |
| Priority date | — |
| Expiry date | Aug 18, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10K19/10
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A pixel current driver comprises a plurality of thin film transistors (TFTs) each having dual gates and for driving OLED layers. A top gate of the dual gates is formed between a source and a drain of each of the thin film transistors, to thereby minimize parasitic capacitance. The top gate is grounded or electrically tied to a bottom gate. The plurality of thin film transistors may be two thin film transistors formed in voltage-programmed manner or five thin film transistors formed in a current-programmed ΔVT-compensated manner. Other versions of the current-programmed circuit with different numbers of thin film transistors are also presented that compensate for δVT. The OLED layer are continuous and vertically stacked on the plurality of thin film transistors to provide an aperture ratio close to 100%.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.