Novel Current-Scaling Current-Mirror a-Si:H TFT Pixel Electrode Circuit with Cascade Capacitor for AM-OLEDs

We proposed the amorphous silicon thin-film transistor (a-Si:H TFT) pixel electrode circuit with current-scaling function that can be used for active-matrix organic light-emitting displays (AM-OLEDs). In contrast to the conventional current-mirror circuit, this circuit with cascaded storage capacitors can provide a high data-to-OLED current ratio without increasing the aSi:H TFT size. Moreover, since the number of signal line is reduced in the proposed pixel electrode circuit, the pixel layout and the driving scheme can be simplified in comparison to previously reported cascade capacitor circuit.