Display device for outputting compensation data based on driving frequency of previous frame

Patent metadata

Field	Value
Publication number	US-12315424-B2
Application number	US-202318387357-A
Country	US
Kind code	B2
Filing date	Nov 6, 2023
Priority date	Jan 31, 2023
Publication date	May 27, 2025
Grant date	May 27, 2025

Abstract

Discussed is a display device including a frequency calculator configured to calculate a driving frequency of a previous frame and compare the driving frequency of the previous frame and a threshold driving frequency, a compensation data calculator configured to calculate compensation data based on a comparison result of the frequency calculator that the driving frequency of the previous frame is lower than the threshold driving frequency a data storage configured to provide the compensation data corresponding to the calculated compensation data to an image data output unity, and the image data output unit configured to output the compensation data to a data driver.

First claim

What is claimed is:

1. A display device comprising:
a frequency calculator configured to calculate a driving frequency of a previous frame, and compare the driving frequency of the previous frame and a threshold driving frequency;
a compensation data calculator configured to calculate compensation data based on a comparison result of the frequency calculator that the driving frequency of the previous frame is lower than the threshold driving frequency;
a data storage configured to provide the compensation data corresponding to the calculated compensation data to an image data output unit; and
the image data output unit configured to output the compensation data to a data driver.

2. The display device of claim 1 , wherein the previous frame is followed by a current frame,
wherein the current frame comprises an active period and a blank period,
wherein the image data output unit receives image data from the data storage and provides the image data to the data driver in the active period, and
wherein the data driver provides an analog data voltage converted from the image data to a pixel of the display device.

3. The display device of claim 2 , wherein the calculation for the driving frequency of the previous frame and the comparison between the driving frequency of the previous frame and the threshold driving frequency by the frequency calculator are performed in the active period of the current frame.

4. The display device of claim 2 , wherein the calculation of the compensation data by the compensation data calculator is performed in the active period of the current frame.

5. The display device of claim 2 , wherein the provision of the compensation data corresponding to the calculated compensation data to the image data output unit by the data storage is performed in the blank period of the current frame.

6. The display device of claim 2 , wherein the current frame is followed by a next frame, the next frame comprises a data preparation period subsequent to the blank period of the current frame, and the data preparation period starts in response to a vertical synchronization signal.

7. The display device of claim 6 , wherein, in the data preparation period of the next frame, the data storage provides gray image data to the image data output unit, and the image data output unit provides the gray image data to the data driver.

8. The display device of claim 2 , wherein, based on a comparison result of the frequency calculator that the driving frequency of the previous frame is higher than the threshold driving frequency, in the blank period, the data storage provides gray image data to the image data output unit, and the image data output unit provides the gray image data to the data driver.

9. The display device of claim 2 , wherein, the current frame is followed by a next frame, the next frame comprises a data preparation period subsequent to the blank period of the current frame, and the data preparation period starts in response to a vertical synchronization signal,
wherein based on a comparison result of the frequency calculator that the driving frequency of the previous frame is higher than the threshold driving frequency, in the blank period, the data storage provides gray image data to the image data output unit, and the image data output unit provides the gray image data to the data driver, and
wherein in the data preparation period of the next frame, the data storage continues to provide gray image data to the image data output unit, and the image data output unit continues to provide the gray image data to the data driver.

10. The display device of claim 2 , wherein the compensation data calculator provides the compensation data corresponding to the calculated compensation data to the data storage in the blank period of the current frame.

11. The display device of claim 1 , wherein the calculation of the compensation data by the compensation data calculator is performed based on image data in the active period of the previous frame.

12. The display device of claim 11 , wherein the compensation data calculator calculates an average value of the image data in the active period of the previous frame, and calculates the compensation data based on the calculated averaged value of the image data of the previous frame.

13. A method of performing a variable refresh rate mode of a display device, the method comprising:
Calculating a driving frequency of a previous frame for the display device, and comparing the driving frequency of the previous frame and a threshold driving frequency;
calculating compensation data based on a comparison result of the comparing that the driving frequency of the previous frame is lower than the threshold driving frequency;
providing the compensation data corresponding to the calculated compensation data to an image data output unit of the display device; and
outputting the compensation data to a data driver of the display device.

14. The method of claim 13 , wherein the previous frame is followed by a current frame,
wherein the current frame comprises an active period and a blank period,
wherein the calculating of the driving frequency of the previous frame and the driving frequency of the previous frame and the threshold driving frequency is performed in the active period of the current frame,
wherein the calculating of the compensation data is performed in the active period of the current frame, and
wherein the outputting of the compensation data corresponding to the calculated compensation data is performed in the blank period of the current frame.

15. A timing controller for a display device having a variable refresh rate (VRR) mode, the timing controller comprising:
a frequency calculator configured to calculate a driving frequency of a previous frame, and compare the driving frequency of the previous frame and a threshold driving frequency;
a data storage configured to store image data;
an image data output unit configured to output the image data received from the data storage to a data driver of the display device; and
a compensation data calculator configured to calculate compensation data based on a signal from the frequency calculator.

16. The timing controller of claim 15 , wherein, when the frequency calculator determines that the driving frequency of the previous frame is less than the threshold driving frequency, the frequency calculator provides the signal to the frequency calculator to calculate the compensation data, and
when the frequency calculator determines that the driving frequency of the previous frame is not less than the threshold driving frequency, the frequency calculator does not provide the signal to the frequency calculator to calculate the compensation data.

17. The timing controller of claim 16 , wherein, when the frequency calculator does not provide the signal to the frequency calculator to calculate the compensation data, the data storage provides a gray image data to the image data output unit to output the gray image data to the data driver in the blank period.

18. The timing controller of claim 17 , wherein the current frame is followed by a next frame, the next frame comprises a data preparation period subsequent to the blank period of the current frame, and
wherein the gray image data is continued to be output to the data driver in the data preparation period of the next frame.

19. The timing controller of claim 16 , wherein, when the frequency calculator does provide the signal to the frequency calculator to calculate the compensation data,

Assignees

• Lg Display Co Ltd

Inventors

• Cho Minho

Classifications

• G09G2300/0852

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