An AC Driving Pixel Circuit Compensating for TFTs Threshold-Voltage Shift and OLED Degradation for AMOLED

Author

Wei-Jing Wu ; Lei Zhou ; Miao Xu ; Li-Rong Zhang ; Ruo-He Yao ; Jun-Biao Peng

Author_Institution

State Key Lab. of Luminescent Mater. & Devices, South China Univ. of Technol., Guangzhou, China

Volume

9

Issue

7

fYear

2013

fDate

41456

Firstpage

572

Lastpage

576

Abstract

This paper presents an ac driving pixel circuit for active-matrix organic light-emitting diode (AMOLED) displays, which is composed of one driving thin-film transistor (TFT), three switching TFTs and one capacitor. The proposed pixel circuit can not only make OLED work at the ac driving mode, but also effectively compensate for the threshold-voltage shift of the driving TFT and the degradation of OLED. Simulation results show that the nonuniformity of the proposed pixel circuit is significantly reduced (<; 10%) with an average value of 4.2% compared with that of the conventional 2T1C pixel circuit, and thus, the brightness uniformity of AMOLED displays can be enhanced. Moreover, a high contrast ratio can be achieved by the proposed pixel circuit due to no light emitting except for the emission period, as well as a relatively high aperture ratio due to a small number of components.

Keywords

LED displays; display instrumentation; driver circuits; organic light emitting diodes; thin film transistors; AC driving pixel circuit; AMOLED display; OLED degradation; TFT; active matrix organic light emitting diode display; brightness uniformity; thin film transistor; threshold voltage shift; Active matrix organic light emitting diodes; Anodes; Capacitors; Degradation; Thin film transistors; Threshold voltage; AC driving; active-matrix organic light-emitting diode (AMOLED); degradation; pixel circuit; threshold voltage shift;

fLanguage

English

Journal_Title

Display Technology, Journal of

Publisher

ieee

ISSN

1551-319X

Type

jour

DOI

10.1109/JDT.2013.2250254

Filename

6479320