A Driving and Compensation Method for AMLED Displays Using Adaptive Reference Generator for High Luminance Uniformity

Abstract

In this brief, we propose a driving method for an active matrix micro-pixelated light-emitting diode (AMLED) display in an attempt to achieve highly uniform luminance using an adaptive reference generator. The proposed driving method compensates for all resistance mismatches not only in a row line but also between the row lines by generating respective reference voltages for all row lines. To verify the proposed driving method, the pixel circuit ICs and pixel driver ICs were fabricated using a $0.18~\mu \text{m}$ standard CMOS process with 6 V high voltage devices. In the measurement, a micro-pixelated LED array with $16\times 16\times $ RGB was driven by the fabricated ICs, and its pixel currents were measured for luminance uniformity of the AMLED display. The measured average deviation of the pixel current for all 768 sub-pixels was 0.79% at a measured average pixel current of $12.003~\mu \text{A}$ , demonstrating that the proposed AMLED display achieved highly uniform luminance. Therefore, the proposed driving method is suitable for AMLED display applications requiring high image quality.