Display device

Patent metadata

Field	Value
Publication number	US-12062340-B2
Application number	US-202217990170-A
Country	US
Kind code	B2
Filing date	Nov 18, 2022
Priority date	Dec 23, 2021
Publication date	Aug 13, 2024
Grant date	Aug 13, 2024

Abstract

According to an aspect of the present disclosure, a display device includes a substrate in which a plurality of sub pixels having different areas is defined; a plurality of light emitting elements each on a corresponding one of the plurality of sub pixels and includes an anode and a cathode; a first anode reset line which is connected to some of the plurality of sub pixels and outputs a first anode reset voltage to anodes of the some of the plurality of sub pixels; and a second anode reset line which is connected to remaining sub pixels of the plurality of sub pixels and outputs a second anode reset voltage to anodes of the remaining sub pixels. Accordingly, according to the present disclosure, different anode reset voltages are applied according to areas of the plurality of sub pixels so that the voltage deviation and the color variation of the anode according to the areas of the plurality of sub pixels may be reduced.

First claim

What is claimed is:

1. A display device, comprising:
a substrate comprising a plurality of sub pixels having different areas, the plurality of sub pixels arranged across a plurality of rows of pixels;
a plurality of light emitting elements, each light emitting element on a corresponding one of the plurality of sub pixels and includes an anode and a cathode;
a first anode reset line connected to a first sub pixel from the plurality of sub pixels that is in a first row from the plurality of rows, the first anode reset line outputting a first anode reset voltage to an anode of a light emitting element from the plurality of light emitting elements that is included in the first sub pixel; and
a second anode reset line connected to a second sub pixel from the plurality of sub pixels that is in the first row with the first sub pixel, the second anode reset line outputting a second anode reset voltage to an anode of a light emitting element from the plurality of light emitting elements that is included in the second sub pixel,
wherein an area of the second sub pixel is larger than an area of the first sub pixel, and a magnitude of the second anode reset voltage is based on the area of the second sub pixel and a magnitude of the first anode reset voltage is based on the area of the first sub pixel and is different from the magnitude of the second anode reset voltage, and
wherein a voltage change of the anode of the light emitting element in the first sub pixel is different from a voltage change of the anode of the light emitting element in the second sub pixel.

2. The display device according to claim 1 , wherein the plurality of sub pixels include:
a third sub pixel connected to the first anode reset line and is in the first row with the first sub pixel and the second sub pixel, and
wherein an area of the second sub pixel is larger than the area of the first sub pixel and an area of the third sub pixel.

3. The display device according to claim 2 , wherein the first sub pixel and the third sub pixel are a red sub pixel and a green sub pixel, respectively, and the second sub pixel is a blue sub pixel.

4. The display device according to claim 2 , wherein the second anode reset voltage is greater than the first anode reset voltage.

5. The display device according to claim 2 , wherein each of the plurality of sub pixels includes:
a driving transistor in which a gate electrode of the driving transistor is connected to a second node and a source electrode and a drain electrode of the driving transistor is connected between a first node and a third node;
a first transistor in which a source electrode and a drain electrode of the first transistor are connected between the second node and the third node;
a second transistor in which a source electrode and a drain electrode of the second transistor are connected between the first node and a data line;
a third transistor in which a source electrode and a drain electrode of the third transistor are connected between a high potential power line and the first node;
a fourth transistor in which a source electrode and a drain electrode of the fourth transistor are connected between the third node and a fourth node;
a fifth transistor in which a source electrode and a drain electrode of the fifth transistor are connected between an initialization line and the third node; and
a sixth transistor in which a drain electrode of the sixth transistor is connected to the fourth node, and
the anode of the light emitting element included in the sub pixel is connected to the fourth node.

6. The display device according to claim 5 , wherein source electrodes of sixth transistors of the first sub pixel and the second sub pixel are connected to the first anode reset line, a source electrode of the sixth transistor of the third sub pixel is connected to the second anode reset line, and
responsive to the sixth transistor being turned on, the first anode reset voltage or the second anode reset voltage is transmitted to the fourth node.

7. The display device according to claim 6 , wherein responsive to the fourth transistor being turned on, a voltage of the fourth node rises by a voltage of the third node.

8. The display device according to claim 6 , wherein responsive to fourth transistors of the first sub pixel and the third sub pixel being turned on, a voltage of the fourth node varies in a range between a voltage of the third node and the first anode reset voltage, and responsive to the fourth transistor of the second sub pixel is turned on, a voltage of the fourth node varies in a range between a voltage of the third node and the second anode reset voltage.

9. The display device according to claim 8 , wherein responsive to the fourth transistor being turned on, a smaller the area of each of the plurality of sub pixels, a larger a voltage change of the fourth node.

10. The display device according to claim 8 , wherein responsive to the fourth transistor being turned on, a voltage change of the fourth node of the second sub pixel is less than a voltage change of the fourth node of the first sub pixel.

11. The display device according to claim 10 , wherein the second anode reset voltage is set to a value obtained by adding a difference between the voltage change of the fourth node of the second sub pixel and the voltage change of the fourth node of the first sub pixel to the first anode reset voltage.

12. The display device according to claim 8 , wherein responsive to the fourth transistor being turned on, a voltage change of the fourth node of the second sub pixel is less than a voltage change of the fourth node of the third sub pixel.

13. The display device according to claim 5 , wherein each of the plurality of sub pixels further includes a parasitic capacitor between the anode and the cathode and a larger the areas of the plurality of sub pixels, a higher a capacitance of the parasitic capacitor.

14. The display device according to claim 13 , wherein responsive to the fourth transistor being turned on, a higher the capacitance of the parasitic capacitor and a smaller a voltage change of the fourth node.

15. The display device according to claim 1 , wherein sub pixels emitting light of a same color among the plurality of sub pixels are connected to a same anode reset line.

16. The display device according to claim 1 , wherein the first anode reset voltage is less than the second anode reset voltage.

17. The display device according to claim 1 , wherein the first anode reset voltage is different from the second anode reset voltage.

Assignees

• Lg Display Co Ltd

Inventors

• Kim Jiyun
• Lee Jung-Min

Classifications

• G09G2310/061

  for resetting or blanking · CPC title

• G09G2300/0842

  forming a memory circuit, e.g. a dynamic memory with one capacitor · CPC title

• G09G2310/0272

  Details of drivers for data electrodes, the drivers communicating data to the pixels by means of a current · CPC title

• G09G2320/0666

  for control of colour parameters, e.g. colour temperature · CPC title

• G09G2320/0214

  with crosstalk due to leakage current of pixel switch in active matrix panels · CPC title