| 摘要 |
The present invention discloses a pixel circuit and a driving method thereof, a display panel, and a display device, so as to improve brightness uniformity. The pixel circuit in the present invention comprises a control sub-circuit, a compensation sub-circuit, a driving transistor and a light emitting device. The present invention enables the driving current that drives the light emitting device to emit light to be uncorrelated with the threshold voltage of the driving transistor, so as to improve display uniformity of the panel. |
| 主权项 |
1. A pixel circuit, comprising:
a control sub-circuit; a compensation sub-circuit; a driving transistor; and a light emitting device, wherein; a gate of the driving transistor is connected with the compensation sub-circuit, a drain of the driving transistor is connected with a variable voltage source, and a source of the driving transistor is connected with the light emitting device, wherein the control sub-circuit is connected with the compensation sub-circuit and controls charging and discharging of the compensation sub-circuit under control of a scanning signal and a charging signal; wherein the control sub-circuit is connected with the driving transistor and the light emitting device and controls the driving transistor to drive the light emitting device to emit light under control of a light-emitting control signal, and wherein the compensation sub-circuit performs electric potential reset under control of the control sub-circuit, and is used for storing a threshold voltage of the driving transistor, so as to compensate the threshold voltage of the driving transistor when the driving transistor drives the light emitting device to emit light, wherein the compensation sub-circuit comprises: a first capacitor; a second capacitor; and a first switch transistor, wherein a first end of the first capacitor is connected with the control sub-circuit and a second end of the second capacitor, wherein a second end of the first capacitor is connected to the gate of the driving transistor and the drain of the first switch transistor, wherein a first end of the second capacitor is connected with a reference voltage source, and the second end of the second capacitor is connected with the first end of the first capacitor; wherein a gate of the first switch transistor is connected with a first gate signal source, the drain of the first switch transistor is connected with the gate of the driving transistor and the second end of the first capacitor, and a source of the first switch transistor is connected with the source of the driving transistor; wherein the control sub-circuit controls charging and discharging of the first capacitor and the second capacitor to enable the electric potential stored at the connection end of the first capacitor and the second capacitor to be reset, and controls the first switch transistor to be switched on, so as to enable the first capacitor to be charged and discharged in a diode connection mode of the driving transistor, thereby enabling the first capacitor to store the threshold voltage of the driving transistor; and wherein the pixel circuit further comprises a fourth switch transistor, wherein a gate of the fourth switch transistor is connected with the first gate signal source, a drain of the fourth switch transistor is directly connected with the second end of the second capacitor and to the first end of the first capacitor, and a source of the fourth switch transistor is connected with the drain of the driving transistor. |
