Display device which senses and compensates for degradation of a pixel and method of driving display device

Patent metadata

Field	Value
Publication number	US-11727863-B2
Application number	US-202217732375-A
Country	US
Kind code	B2
Filing date	Apr 28, 2022
Priority date	Aug 13, 2021
Publication date	Aug 15, 2023
Grant date	Aug 15, 2023

Abstract

A display device including pixels; a controller configured to generate first compensation data based on first sensing data with respect to threshold voltages of driving transistors of the pixels which are sensed during a first sensing period, to generate second compensation data based on second sensing data with respect to mobilities of the driving transistors of the pixels which are sensed during the first sensing period, to generate third compensation data based on third sensing data with respect to mobility change amounts of the driving transistors of the pixels which are sensed using image data for sensing compensated based on the first and second compensation data during a second sensing period, and to compensate input image data based on the first, second, and third compensation data to generate compensated image data; and a data driver configured to provide data voltages to the pixels based on the compensated image data.

First claim

What is claimed is:

1. A display device comprising:
a display panel including pixels;
a controller configured to generate first compensation data based on first sensing data with respect to threshold voltages of driving transistors of the pixels which are sensed during a first sensing period after a power-off of the display device, to generate second compensation data based on second sensing data with respect to mobilities of the driving transistors of the pixels which are sensed during the first sensing period, to generate third compensation data based on third sensing data with respect to mobility change amounts of the driving transistors of the pixels which are sensed using image data for sensing compensated based on the first compensation data and the second compensation data during a second sensing period during an image display of the display device, and to compensate input image data based on the first compensation data, the second compensation data, and the third compensation data to generate compensated image data; and
a data driver configured to provide a data voltage to each of the pixels based on the compensated image data,
wherein:
the controller includes:
a first compensator configured to generate the first compensation data based on the first sensing data;
a second compensator configured to generate the second compensation data based on the second sensing data;
a third compensator configured to generate the third compensation data based on the third sensing data; and
an image data compensator configured to compensate the image data for sensing based on the first compensation data and the second compensation data, and to compensate the input image data based on the first compensation data, the second compensation data, and the third compensation data;

the third compensator includes:
a compensation target selector configured to select a compensation target;
a compensation data generator configured to generate the third compensation data based on the third sensing data and the compensation target; and
a compensation data controller configured to control the third compensation data based on a parameter; and

the compensation data controller is configured to multiply gains of the third compensation data by a panel parameter determined according to a size of the display panel.

2. The display device of claim 1 , wherein the mobilities of the driving transistors of the pixels which are sensed during the first sensing period are sensed using the image data for sensing compensated based on the first compensation data.

3. The display device of claim 1 , wherein the compensation target selector is configured to select one of a representative value of the second sensing data, a representative value of the third sensing data, and a representative value of fourth sensing data with respect to the mobilities of the driving transistors of the pixels which are sensed using the image data for sensing during a third sensing period after a power-on of the display device as the compensation target.

4. The display device of claim 1 , wherein the compensation target selector is configured to gradually change the compensation target from a first voltage level to a second voltage level in a predetermined transition time when the compensation target changes from the first voltage level to the second voltage level.

5. The display device of claim 1 , wherein the compensation data controller is configured to multiply the gains of the third compensation data by a temperature parameter determined according to a temperature of the display panel.

6. The display device of claim 1 , wherein the compensation data controller is configured to multiply the gains of the third compensation data by a grayscale parameter determined according to grayscales of the input image data.

7. The display device of claim 1 , further comprising:
a sensing driver configured to provide the first sensing data, the second sensing data, and the third sensing data to the controller based on a sensing voltage receiving from each of the pixels.

8. The display device of claim 7 , further comprising:
a scan driver configured to provide a first scan signal and a second scan signal to each of the pixels.

9. The display device of claim 8 , wherein each of the pixels includes:
a switching transistor configured to transmit the data voltage from the data driver in response to the first scan signal;
a driving transistor configured to generate a driving current based on the data voltage;
a storage capacitor configured to store the data voltage;
a light emitting diode configured to emit light based on the driving current; and
a sensing transistor configured to transmit the sensing voltage to the sensing driver in response to the second scan signal.

10. A method of driving a display device, the method comprising:
generating first compensation data based on first sensing data with respect to threshold voltages of driving transistors of the pixels which are sensed during a first sensing period after a power-off of the display device;
generating second compensation data based on second sensing data with respect to mobilities of the driving transistors of the pixels which are sensed during the first sensing period;
generating third compensation data based on third sensing data with respect to mobility change amounts of the driving transistors of the pixels which are sensed using image data for sensing compensated based on the first compensation data and the second compensation data during a second sensing period during an image display of the display device;
compensating input image data based on the first compensation data, the second compensation data, and the third compensation data to generate compensated image data; and
providing data voltages to the pixels based on the compensated image data,
wherein:
generating the third compensation data includes:
selecting a compensation target;
generating the third compensation data based on the third sensing data and the compensation target; and
controlling the third compensation data based on a parameter; and

controlling the third compensation data includes multiplying gains of the third compensation data by a panel parameter determined according to a size of the display device.

11. The method of claim 10 , wherein the mobilities of the driving transistors of the pixels which are sensed during the first sensing period are sensed using the image data for sensing compensated based on the first compensation data.

12. The method of claim 10 , wherein selecting the compensation target includes:
selecting one of a representative value of the second sensing data, a representative value of the third sensing data, and a representative value of fourth sensing data with respect to the mobilities of the driving transistors of the pixels which are sensed using the image data for sensing during a third sensing period after a power-on of the display device as the compensation target.

13. The method of claim 10 , wherein selecting the compensation target includes:
gradually changing the compensation target from a first voltage level to a second voltage level in a predetermined transition time when the compensation target changes from the first voltage level to the second voltage level.

14. The method of claim 10 , wherein controlling the third compensation data further includes:
multiplying the gains of the third compensation data by a temperature parameter determined according to a temperature of the display device.

15. The method of claim 10 , wherein controlling the third compensation data further inc

Assignees

• Samsung Display Co Ltd

Inventors

• An Boyoung
• Jeong Ji-Woong
• Lee Wook
• Min Jungki

Classifications

• G09G3/32 Primary

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• G09G2300/043

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• G09G2300/0842

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

• G09G2320/041

  Temperature compensation · CPC title

• G09G2320/045

  Compensation of drifts in the characteristics of light emitting or modulating elements · CPC title