Display device and driving method thereof

• US 9,269,290 B2
• Filed: 07/11/2014
• Issued: 02/23/2016
• Est. Priority Date: 01/20/2014
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Inventors: Chae, Min-Yup, Moon, Hoi Sik, Nam, Gwang Ho, Lee, Chang-Soo, Choi, Jae-Seok, Choi, Hak-Mo
• Primary Examiner(s): Nguyen, Kevin M
• Application Number:
  US14/329,233
• Publication Number:
  US 20150206472A1
• Time in Patent Office: 592 Days
• US Class Current: 1/1
• CPC Class Codes: G09G 2320/0247 Flicker reduction other than flicker reduction circuits used for single beam cathode-ray tubes
• CPC Class Codes: G09G 2320/0252 Improving the response speed
• CPC Class Codes: G09G 2320/0261 in the context of movement of objects on the screen or movement of the observer relative to the screen
• CPC Class Codes: G09G 2320/106 Determination of movement vectors or equivalent parameters within the image
• CPC Class Codes: G09G 3/20 for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
• CPC Class Codes: G09G 3/2007 Display of intermediate tones
• CPC Class Codes: G09G 3/3666 with the matrix divided into sections
• CPC Class Codes: G09G 3/3696 Generation of voltages supplied to electrode drivers

Abstract

A display device is provided. The display device includes pixels, a data driver, a signal controller, a data processor. The data driver is configured to apply a first data voltage to a first pixel. The signal controller is configured to transfer an image data signal and a data control signal for controlling an operation of the data driver. The data processor is configured to detect a first region including a moving in a first image signal, to apply a first dynamic capacitance control (DCC) to the first region, to apply a second DCC to a second region other than the moving pattern region, to generate the second image signal by combining the first region to which the first DCC is applied and the second region to which the second DCC is applied, and to transfer the second image signal to the signal controller.

Claims

1. A display device, comprising:

a plurality of pixels;

a data driver configured to apply a first data voltage to a first data line of a plurality of data lines, wherein the first data line is connected to a first pixel of the plurality of pixels;

a signal controller configured to transfer an image data signal and a data control signal for controlling an operation of the data driver, wherein the image data signal includes a first image signal and a second image signal; and

a data processor configured to detect a first region including a moving pattern in the first image signal, to apply a first dynamic capacitance control (DCC) to the first region, to apply a second DCC to a second region other than the moving pattern region, to generate the second image signal by combining the first region to which the first DCC is applied and the second region to which the second DCC is applied, and to transfer the second image signal to the signal controller,

wherein during a first time period, the first data voltage is higher than a reference data voltage corresponding to a first luminance to be displayed by a first predetermined level, or during a second time period, the first data voltage is lower than the reference data voltage by a second predetermined level, and

wherein a rising time and a falling time of luminance of the first pixel are the same as each other when the first DCC is applied, and the rising time and the falling time of the luminance of the first pixel are not controlled when the second DCC is applied.

2. The display device of claim 1, wherein the data processor includes:

a frame memory configured to store the first image signal in a frame unit;

a moving pattern detector configured to divide an image signal of a current frame into a plurality of current detection blocks, and an image signal of a previous frame stored in the frame memory into a plurality of previous detection blocks, respectively, to detect a detection block including the moving pattern among the plurality of current detection blocks, and to transfer the plurality of current detection blocks to a first DCC unit or a second DCC unit;

the first DCC unit configured to perform the first DCC on the plurality of current detection blocks transferred from the moving pattern detector; and

the second DCC unit configured to perform the second DCC on the plurality of current detection blocks transferred from the moving pattern detector.

3. The display device of claim 2, wherein the data processor further includes a data buffer configured to hold the first image signal in the frame unit, and to transfer the held first image signal to the frame memory and the moving pattern detector.

4. The display device of claim 2, wherein the plurality of current detection blocks and the plurality of previous detection blocks have the same size.

5. The display device of claim 4, wherein the moving pattern detector is configured to determine whether a first difference between an average luminance of the plurality of current detection blocks and an average luminance of the plurality of previous detection blocks is smaller than a first reference value, and to transfer the plurality of current detection blocks to the second DCC unit when the first difference is larger than or equal to the first reference value.

6. The display device of claim 5, wherein the moving pattern detector is configured to determine whether a second difference between luminance of each pixel in the plurality of current detection blocks and luminance of each pixel in the previous detection blocks is larger than a second reference value when the first difference is smaller than the first reference value.

7. The display device of claim 6, wherein the moving pattern detector is configured to transfer the plurality of current detection blocks to the second DCC unit when the second difference is smaller than or equal to the second reference value.

8. The display device of claim 6, wherein, the moving pattern detector is configured to transfer the plurality of current detection blocks to the first DCC unit when the second difference is larger than the second reference value.

9. The display device of claim 1, wherein each of the plurality of pixels includes:

a pixel electrode to which a data voltage is applied;

a common electrode to which a common voltage is applied; and

a liquid crystal layer provided between the pixel electrode and the common electrode.

10. The display device of claim 9, wherein the rising time is a time required to increase the luminance of the first pixel from 10% to 90% of an amount of the increased luminance.

11. The display device of claim 10, wherein, after the first time period of the rising time, the first data voltage is changed to the reference data voltage when the luminance of the first pixel is substantially equal to the first luminance to be displayed.

12. The display device of claim 9, wherein the falling time is a time required to decrease the luminance of the first pixel from 90% to 10% of an amount of the decreased luminance.

13. The display device of claim 12, wherein, after the second time period of the falling time, the first data voltage is changed to the reference voltage when the luminance of the first pixel is substantially equal to the first luminance to be displayed.

14. A method for driving a display device, comprising:

receiving first frame data;

receiving second frame data after the first frame has been received data;

dividing the received first frame data into a plurality of first detection blocks;

dividing the received second frame data into a plurality of second detection blocks;

detecting a detection block including a moving pattern among the plurality of second detection blocks;

applying a first dynamic capacitance control (DCC) to the detection block including the moving pattern; and

applying a second DCC to a detection block from among the plurality of second detection blocks in which the moving pattern is not included,

wherein a first data voltage applied to a first pixel in the display device is higher than a reference voltage corresponding to a first luminance to be displayed by a first predetermined level, or lower than the reference voltage by a second predetermined level, and

wherein a rising time and a falling time of luminance of the first pixel are the same as each other when the first DCC is applied, and the rising time and the falling time of the luminance of the first pixel are not controlled when the second DCC is applied.

15. The method of claim 14, further comprising storing the first frame data in a frame unit.

16. The method of claim 14, wherein the plurality of first detection blocks and the plurality of second detection blocks have the same size.

17. The method of claim 14, wherein

the detecting of the detection block including the moving pattern among the plurality of second detection blocks includes:

determining whether a first difference between an average luminance of the plurality of second detection blocks and an average luminance of the plurality of first detection blocks is smaller than a first reference value; and

applying the second DCC to the plurality of second detection blocks when the first difference is larger than or equal to the first reference value.

18. The method of claim 17, wherein the detecting of the detection block including the moving pattern among the plurality of detection blocks further includes determining whether a second difference between luminance of each pixel in the plurality of second detection blocks and luminance of each pixel in the plurality of first detection blocks is larger than a second reference value when the first difference is smaller the first reference value.

19. The method of claim 18, wherein the detecting of the detection block including the moving pattern among the plurality of detection blocks further includes applying the second DCC when the second difference is equal to or smaller than the second reference value.

20. The method of claim 18, wherein the detecting of the detection block including the moving pattern among the plurality of detection blocks further includes applying the first DCC when the second difference is larger than the second reference value.

21. A data processor in a display device, comprising:

a frame memory configured to store a first image signal in a frame unit;

a moving pattern detector configured to divide an image signal of a current frame into a plurality of current detection blocks, to divide an image signal of a previous frame stored in the frame memory into a plurality of previous detection blocks, to detect a detection block including a moving pattern among the plurality of current detection blocks, and to transfer the plurality of current detection blocks to a first dynamic capacitance control (DCC) unit or a second DCC unit depending on whether the plurality of current detection blocks includes the moving pattern;

the first dynamic capacitance control (DCC) unit configured to perform a first DCC on the plurality of current detection blocks transferred from the moving pattern detector;

the second DCC unit configured to apply a second DCC on the plurality of current detection blocks transferred from the moving pattern detector; and

a data output section configured to generate a second image signal by combining the output image signals from the first DCC unit and the second DCC unit.