Display device, method for driving display device, and electronic device
A display device includes a pixel array unit in which pixel circuits are disposed in a matrix form, the pixel circuits each including a light emission unit, a write transistor that writes a signal voltage of a video signal, a retention capacitor that retains the signal voltage written by the write transistor, and a drive transistor that drives the light emission unit on the basis of the signal voltage retained by the retention capacitor; and a common line that is wired along a pixel row, for each pixel row. The pixel circuit includes a switching transistor which selectively connects the common line and a source electrode of the drive transistor.
1. A display device comprising: a pixel array unit in which pixel circuits are disposed in a matrix form, the pixel circuits respectively including a light emission unit, a write transistor that writes a signal voltage of a video signal in response to a first control signal from a first control signal line, a retention capacitor that retains the signal voltage written by the write transistor, and a drive transistor that drives the light emission unit on the basis of the signal voltage retained by the retention capacitor; and a common line that is wired along a pixel column, for each pixel column, wherein the pixel circuit includes a switching transistor which selectively connects the common line and a source electrode of the drive transistor over a period from before a threshold value correction process begins to alter a mobility correction process ends, in response to a second control signal from a second control signal line.
2. The display device according to claim 1 , comprising:
a switch element that is provided in a peripheral circuit region of the pixel array unit and selectively applies a predetermined voltage to the common line.
3. The display device according to claim 2 ,
wherein the threshold value correction process changes a source voltage of the drive transistor toward a voltage obtained by subtracting a threshold value voltage of the drive transistor from an initialization voltage of a gate voltage of the drive transistor, with reference to the initialization voltage.
4. The display device according to claim 3 ,
wherein the switching transistor and the switch element enter a conductive state before the threshold value correction process to write a predetermined voltage into the source electrode of the drive transistor.
5. The display device according to claim 4 ,
wherein the switch element enters a non-conductive state after writing of the predetermined voltage and the initial voltage to execute the threshold value correction process.
6. The display device according to claim 5 ,
wherein the mobility correction process applies negative feedback to a potential difference between a gate electrode and the source electrode of the drive transistor by a correction amount corresponding to a current flowing in the drive transistor, to correct a mobility of the drive transistor, and
the threshold value correction process and the mobility correction process are executed within 1 horizontal period.
7. The display device according to claim 1 ,
wherein the common line is provided in a state in which the common line overlaps a wire that supplies a fixed voltage to the pixel circuit.
8. The display device according to claim 7 ,
wherein the wire that supplies the fixed voltage is a power supply line that supplies a drive current to the drive transistor.
9. The display device according to claim 7 ,
wherein the wire that supplies the fixed voltage is a wire that applies a back gate voltage to the drive transistor.
10. The display device according to claim 1 ,
wherein a parasitic capacitor of the common line increases a capacitance value of the entire pixel circuit.
11. The display device according to claim 10 ,
wherein the parasitic capacitor of the common line compensates for a shortage of a capacitance value of an equivalent capacitor of the light emission unit.
12. The display device according to claim 10 ,
wherein a capacitance value of the parasitic capacitor of the common line is larger than a capacitance value of a parasitic capacitor of the retention capacitor.
13. The display device according to claim 1 , comprising:
a write scanning unit that drives the write transistor; and
a control scanning unit that drives the switching transistor,
wherein the write scanning unit and the control scanning unit are provided in a peripheral circuit region on the same side with respect to the pixel array unit.
14. A method for driving a display device including: a pixel array unit in which pixel circuits are disposed in a matrix form, the pixel circuits respectively including a light emission unit, a write transistor that writes a signal voltage of a video signal in response to a first control signal from a first control signal line, a retention capacitor that retains the signal voltage written by the write transistor, and a drive transistor that drives the light emission unit on the basis of the signal voltage retained by the retention capacitor; and a common line that is wired along a pixel column, for each pixel column, wherein, in the pixel circuit including a switching transistor which selectively connects the common line and a source electrode of the drive transistor over a period from before a threshold value correction process begins to after a mobility correction process ends, in response to a second control signal from a second control signal line, a capacitance value of a pixel capacitor increases as the switching transistor enters a conductive state.
15. An electronic apparatus comprising a display device that includes: a pixel array unit in which pixel circuits are disposed in a matrix form, the pixel circuits respectively including a light emission unit, a write transistor that writes a signal voltage of a video signal in response to a first control signal from a first control signal line, a retention capacitor that retains the signal voltage written by the write transistor, and a drive transistor that drives the light emission unit on the basis of the signal voltage retained by the retention capacitor; and a common line that is wired along a pixel column, for each pixel column, wherein the pixel circuit includes a switching transistor which selectively connects the common line and a source electrode of the drive transistor over a period from before a threshold value correction process begins to after a mobility correction process ends, in response to a second control signal from a second control signal line.
16. The display device according to claim 1 , the pixel circuits respectively including an auxiliary capacitor disposed in parallel with the light emission unit.