Amorphous silicon TFT-based active-matrix organic polymer LEDs

We report active-matrix organic polymer light-emitting displays (LEDs) based on a three hydrogenated amorphous silicon (a-Si:H) thin-film transistor (TFT) pixel electrode circuit that supplies a continuous output current to organic polymer light-emitting devices. The output current level drift induced by either process variations or device aging can be reduced in this design by adjusting the driver TFT operating point with the active resistor. Our first green light-emitting engineering prototype had a brightness of 120 cd/m/sup 2/ and fill factor of about 45%.