Patent ID: 9613567
Date: 2017-04-04
CPC Classifications: G09G

Claim:
1. A display device comprising: at least one pixel circuit including: a light-emitting element, a holding capacitor to hold a gradation voltage corresponding to gradation data, a driving transistor to provide the light-emitting element with a driving current according to the gradation voltage, a first switch transistor connected between an initialization voltage line for transferring an initialization voltage and a gate of the driving transistor, the first switch transistor to be turned on or off according to a first scan line signal, and a second switch transistor connected between the gate and a drain of the driving transistor, the second switch transistor to be turned on or off according to a second scan line signal; and a control circuit to output the first scan line signal, the second scan line signal, and the initialization voltage, wherein: during a first period, the control circuit turns on the first switch transistor and turns off the second switch transistor to set charges of the holding capacitor to an initial state using a first initialization voltage having a first voltage level as the initialization voltage; during a second period, the control circuit turns off the first switch transistor and turns on the second switch transistor to charge the holding capacitor based on a first gradation voltage corresponding to first gradation data using the first initialization voltage as the initialization voltage; during a third period, the control circuit turns off the first switch transistor and the second switch transistor to switch the initialization voltage from the first initialization voltage to a second initialization voltage having a second voltage level different from the first voltage level; during a fourth period, the control circuit turns off the first switch transistor and turns on the second switch transistor to charge the holding capacitor based on a second gradation voltage based on the second initialization voltage, the second gradation voltage corresponding to second gradation data; during a fifth period, the control circuit drives the light-emitting element according to the second gradation voltage when the driving transistor is turned on.