V _t Compensated voltage-data a-Si TFT AMOLED pixel circuits

Abstract

Active-matrix organic light-emitting-diode (AMOLED) displays are now entering the marketplace. The use of a thin-film-transistor (TFT) active matrix allows OLED displays to be larger in size, higher in resolutions and lower in power dissipation than is possible using a conventional passive matrix. A number of TFT active-matrix pixel circuits have been developed for luminance control, while correcting for initial and electrically stressed TFT parameter variations. Previous circuits and driving methods are reviewed. A new driving method is presented in which the threshold-voltage (V t) compensation performance, along with various circuit improvements for amorphous-silicon (a-Si) TFT pixel circuits using voltage data, are discussed. This new driving method along with various circuit improvements is demonstrated in a state-of-the-art 20-in. a-Si TFT AMOLED HDTV.