Active matrix display devices

A method of driving an active matrix display device comprising an array of current driven light emitting display pixels, each pixel comprising an display element (2) and an amorphous silicon drive transistor (TD) for driving a current through the display element, the method comprising, for each pixel:

• driving a current through the drive transistor (TD) to ground, and charging a first capacitor (C1) to the resulting gate-source voltage;
• discharging the first capacitor (C1) until the drive transistor turns off, the first capacitor thereby storing a threshold voltage;
• charging a second capacitor (C2), in series with the first capacitor between the gate and source or drain of the drive transistor, to a data input voltage;
• and
• using the drive transistor (TD) to drive a current through the display element using a gate voltage that is derived from the voltages across the first and second capacitors (C1, C2).