DISPLAY DEVICE

• US 20190318685A1
• Filed: 04/12/2019
• Published: 10/17/2019
• Est. Priority Date: 04/12/2018
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Group)
• Original Assignee: Samsung Display Company Limited (Samsung Group)
• Inventors: PARK, Sehyuk, LEE, Hyojin, NAM, Hui
• Granted Patent: US 11,030,939 B2
• Time in Patent Office: Days
• CPC Class Codes: G09G 2300/0443 with several sub-pixels for the same colour in a pixel, not specifically used to display gradations G09G3/364 takes precedence
• CPC Class Codes: G09G 2300/0452 Details of colour pixel setup, e.g. pixel composed of a red, a blue and two green components
• CPC Class Codes: G09G 2300/0852 being a dynamic memory with more than one capacitor
• CPC Class Codes: G09G 2310/027 Details of drivers for data electrodes, the drivers handling digital grey scale data, e.g. use of D/A converters
• CPC Class Codes: G09G 2310/0278 Details of driving circuits arranged to drive both scan and data electrodes
• CPC Class Codes: G09G 2310/0289 Details of voltage level shifters arranged for use in a driving circuit
• CPC Class Codes: G09G 2310/08 Details of timing specific for flat panels, other than clock recovery
• CPC Class Codes: G09G 2320/0204 Compensation of DC component across the pixels in flat panels
• CPC Class Codes: G09G 2320/0233 Improving the luminance or brightness uniformity across the screen
• CPC Class Codes: G09G 2320/0285 using tables for spatial correction of display data
• CPC Class Codes: G09G 2370/04 Exchange of auxiliary data, i.e. other than image data, between monitor and graphics controller
• CPC Class Codes: G09G 3/32 semiconductive, e.g. using light-emitting diodes [LED]

Abstract

A display device is capable of improving the image quality, the display device including: a display panel; a pixel on the display panel and including at least one light emitting element; a timing controller configured to receive an image data signal of the pixel and to compensate for a gray value of the image data signal based on the number of light emitting elements of the pixel to generate a compensated image data signal; and a data driver configured to select a compensation data signal corresponding to the compensated image data signal from the timing controller and to apply the compensation data signal to the pixel.

Claims

1. A display device comprising:

a display panel;

a pixel on the display panel, the pixel comprising at least one light emitting element;

a timing controller configured to receive an image data signal of the pixel and to compensate for a gray value of the image data signal based on the number of light emitting elements of the pixel to generate a compensated image data signal; and

a data driver configured to select a compensation data signal corresponding to the compensated image data signal from the timing controller and to apply the compensation data signal to the pixel.

2. The display device of claim 1, wherein, as the number of light emitting elements of the pixel is smaller, the compensated image data signal has a smaller gray value.

3. The display device of claim 2, wherein the timing controller is configured to compare the number of light emitting elements of the pixel with a predetermined reference value, and to generate the compensated image data signal based on the comparison result.

4. The display device of claim 3, wherein, when the number of light emitting elements of the pixel is less than the reference value, the compensated image data signal has a gray value less than that of the image data signal.

5. The display device of claim 4, wherein, as a difference between the number of light emitting elements of the pixel and the reference value is greater, the compensated image data signal has a smaller gray value.

6. The display device of claim 3, wherein, when the number of light emitting elements of the pixel is greater than the reference value, the compensated image data signal has a gray value greater than that of the image data signal.

7. The display device of claim 6, wherein, as a difference between the number of light emitting elements of the pixel and the reference value is greater, the compensated image data signal has a greater gray value.

8. The display device of claim 1, further comprising a look-up table in which the number of light emitting elements of the pixel is stored.

9. The display device of claim 1, wherein at least one of the light emitting elements is a nano-light emitting element.

10. The display device of claim 1, wherein the compensation data signal from the data driver is applied to the pixel through a data line of the display panel.

11. The display device of claim 10, wherein the pixel comprises:

a first switching element comprising a gate electrode connected to a gate line of the display panel, the first switching element being connected between the data line and a node;

a second switching element comprising a gate electrode connected to the node, the second switching element being connected between a first driving power line of the display panel and a first electrode of the light emitting element; and

a capacitor connected between the node and the first driving power line.

12. The display device of claim 11, wherein a second electrode of the light emitting element is connected to a second driving power line of the display panel.

13. A display device comprising:

a display panel comprising a pixel connected to a first driving power line, a second driving power line, a data line, and a first compensation line; and

a driving circuit configured to generate a first compensation voltage based on the number of light emitting elements of the pixel, and to apply the first compensation voltage to the first compensation line,

wherein the pixel comprises;

a driving switching element configured to receive a data signal from the data line;

at least one light emitting element connected to the driving switching element; and

a first compensation switching element comprising a gate electrode connected to the first compensation line, the first compensation switching element being connected between the first driving power line and the driving switching element.

14. The display device of claim 13, wherein, as the number of light emitting elements of the pixel is smaller, the first compensation voltage has a smaller value.

15. The display device of claim 14, wherein the driving circuit is configured to compare the number of light emitting elements of the pixel with a predetermined reference value, and to generate the first compensation voltage based on the comparison result.

16. The display device of claim 15, wherein, when the number of light emitting elements of the pixel is less than the reference value, the first compensation voltage has a value less than that of a predetermined reference compensation voltage.

17. The display device of claim 16, wherein, as a difference between the number of light emitting elements of the pixel and the reference value is greater, the first compensation voltage has a smaller value.

18. The display device of claim 15, wherein, when the number of light emitting elements of the pixel is greater than the reference value, the first compensation voltage has a value greater than that of a predetermined reference compensation voltage.

19. A display device comprising:

a display panel comprising a pixel connected to a first driving power line, a second driving power line, a data line, and a first compensation line; and

a driving circuit configured to generate a first compensation voltage based on the number of light emitting elements of the pixel, and to apply the first compensation voltage to the first compensation line,

wherein the pixel comprises;

a driving switching element configured to receive a data signal from the data line;

at least one light emitting element connected to the driving switching element; and

a first compensation switching element comprising a gate electrode connected to the first compensation line, the first compensation switching element being connected between the light emitting element and the second driving power line.

20. The display device of claim 19, wherein, as the number of light emitting elements of the pixel is smaller, the first compensation voltage has a smaller value.