The
ripple component superimposed on the drive power source Va applied to the source
electrode of a
light emission drive
transistor Tr2 is extracted by a
ripple component extraction circuit 14, and the
ripple component is supplied to one input terminal of a
voltage addition circuit 15. A data
voltage Vdata transmitted via a data line is input to the other input terminal of the
voltage addition circuit 15. Accordingly, in the voltage addition circuit 15, the ripple component extracted by the ripple component extraction circuit 14 is added to the data voltage Vdata treating the data voltage Vdata as the base. Its output is supplied to a scan selection
transistor designated by reference character SW1 as Vgate, and the
transistor Tr1 is turned on at an addressing time so that the Vgate is supplied to the gate of the
light emission drive transistor Tr2. Thus, the gate-to-source voltage Vgs of the
light emission drive transistor Tr2 represents an approximately constant value all the time regardless of timing of addressing. Therefore, a problem that
intensity change occurs for each
scan line so that the display quality of an image is considerably deteriorated can be avoided.