A Pixel Structure Using Block Emission Driving Method for High Image Quality in Active Matrix Organic Light-Emitting Diode Displays

Abstract

In this paper, we propose a pixel structure and timing diagram using the block emission (BE) driving method to improve the image quality of high-resolution active matrix organic light-emitting diode (AMOLED) displays. The proposed pixel structure reduces the boundary error pattern between blocks by adjusting the timing of the compensation (comp) signal for the threshold voltage variation. The test patterns, which include a pixel array and unit pixels, are designed for a 10-inch quadruple high-definition resolution format and are fabricated to verify the image quality of the AMOLED displays. The measurement results show that the emission current error at the boundary between blocks is reduced from +11% to less than +/- 1% by adjusting the timing of the comp signal. Also, the emission current error caused by the threshold voltage variation of the driving thin film transistors is reduced from +/- 8.36% to +/- 2.77% at a gray level of 175 by using the BE driving method. Therefore, the proposed pixel structure improves image quality in high-resolution AMOLED displays.