Patent attributes
To reduce variations in output current of individual pixels resulting from variations in threshold voltage of the MOS transistor T1 provided in each pixel, the threshold voltage of the MOS transistor T1 of each pixel is measured to acquire compensation data with which to correct the output current from the individual pixels. To acquire this compensation data, first, a MOS transistor T2 is turned on to apply a direct-current voltage VRB to the gate of the MOS transistor T1, and the MOS transistor T3 is turned off to disconnect the gates of the MOS transistors T1 and T4 from each other. Next, in this state, by turning a signal φVPS first to a low voltage and then to a voltage close to a direct-current voltage VPD, a negative electric charge is accumulated in the MOS transistor T1. A voltage resulting from this negative electric charge is applied to the gate of the MOS transistor T4, and thus the MOS transistor T5 is turned on, causing an output current to be fed to an output signal line 6 in accordance with the voltage applied to the gate of the MOS transistor T4.
