Patent ID: 8674912
Filing Date: 2014-03-18
Classification: G09G

Abstract:
1. An image display device, comprising: a plurality of pixel circuit groups each including at least one pixel circuit; a first power supply line connected to each pixel circuit of the plurality of pixel circuit groups; a second power supply line connected to each pixel circuit of the plurality of pixel circuit groups; a driving circuit for supplying a data signal and a scanning signal to each pixel circuit; and a switch unit provided at an end of the first power supply line and outside an area occupied by the pixel circuits: wherein the switch unit selectively supplies one of a power supply potential and a predetermined potential to the first power supply line; and wherein the switch unit is shared among a plurality of rows; wherein each pixel circuit comprises: a lighting control switch provided between one end of the light emitting element and the drain electrode of the driving transistor, wherein: each pixel circuit operates to provide a light emission period, a discharge period and a write period; the driving transistor is comprised of a p-channel type transistor; in the write period, the driving circuit selects the pixel circuit groups one by one to cause the storage capacitor in each pixel circuit included in the selected one of the pixel circuit groups to store a potential difference between the data signal line and the gate electrode of the driving transistor; in the light emission period which is common to the pixel circuit groups, the driving circuit causes the light emitting element in each pixel circuit to emit light of an intensity corresponding to the potential difference; in the discharge period which is different from the write period and the light emission period, the reset switch is connected to discharge the storage capacitor through the light emitting element; a source electrode of the driving transistor is connected to the first power supply line; and another end of the light emitting element is connected to the second power supply line, the second power supply line is supplied with a reference potential; and in the discharge period, the switch unit changes potential of the source electrode of the driving transistor to the predetermined potential to set electric charges stored in the light emitting element to a predetermined reference state.