Apparatus for driving a display panel with compensation for heat caused by proximity to light source, and method thereof

• US 8,830,280 B2
• Filed: 07/24/2013
• Issued: 09/09/2014
• Est. Priority Date: 01/18/2010
• Status: Active Grant

• Current Assignee: TCL China Star Optoelectronics Technology Co. Ltd. (TCL Technology Group Corp.)
• Original Assignee: Samsung Display Company Limited (Samsung Group)
• Inventors: Lee, Hyoung-Rae, Lee, Gyu-Su, Um, Min-Sik, Lee, Sang-Won, Kang, Duk-Hwan
• Primary Examiner(s): Bost, Dwayne
• Assistant Examiner(s): STERNBANE, LAURENCE J
• Application Number:
  US13/949,793
• Publication Number:
  US 20130307886A1
• Time in Patent Office: 412 Days
• Field of Search: 345204-215, 345690-699, 362600-634
• US Class Current: 345/690
• 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 2320/041 Temperature compensation
• CPC Class Codes: G09G 3/2011 by amplitude modulation
• CPC Class Codes: G09G 3/3406 Control of illumination source illumination devices structurally associated with liquid crystal cells G02F1/1336
• CPC Class Codes: G09G 5/06 using colour palettes, e.g. look-up tables

Abstract

A driving unit of a display panel includes a control part, a gate driving part, a grayscale compensating part, and a data driving part. The control part provides a control signal and a grayscale signal. The gate driving part provides a gate signal to the display panel. The display panel is divided into a plurality of blocks according to a distance from a light source to each of the blocks. The grayscale compensating part outputs a compensating signal of an n-th frame using look-up tables, and the look-up tables respectively correspond to the blocks of the display panel. The data driving part converts the compensating signal of the n-th frame into a grayscale voltage and provides the grayscale voltage to the display panel. Accordingly, the driving unit of the display panel may improve a response speed of liquid crystals and display quality.

Claims

1. A method of driving a display panel, comprising:

providing grayscale signals to a display panel, the display panel being divided into blocks according to a distance from a light source to each of the blocks;

calibrating the grayscale signals to form compensating signals, the compensating signals respectively corresponding to the blocks; and

driving each block of the display panel using each corresponding compensating signal, to compensate for temperature differences in the blocks caused by heat from the light source.

2. The method of claim 1, wherein calibrating the grayscale signals to the compensating signals comprises determining the compensating signals of an n-th frame using look-up tables, the look-up tables respectively corresponding to the blocks of the display panel, and “

n”

being a natural number.

3. The method of claim 2, wherein determining the compensating signal of the n-th frame comprises:

storing the grayscale signal of an (n-1)-th frame;

selecting the look-up tables; and

calibrating the compensating signals of the n-th frame using the grayscale signal of the (n-1)-th frame and the grayscale signal of the n-th frame in each of the selected look-up tables.

4. The method of claim 3, wherein:

selecting the look-up tables comprises counting a number of pulses of a gate clock signal; and

the look-up tables are selected according to the number of pulses.

5. The method of claim 3, wherein:

selecting the look-up tables comprises counting a number of pulses of a data clock signal; and

the look-up tables are selected according to the number of pulses of the data clock signal.

6. The method of claim 3, wherein the look-up tables are selected in response to a temperature signal of the display panel.

7. The method of claim 3, wherein the look-up tables are selected in response to a control signal including a gate clock signal and a data clock signal.

8. The method of claim 7, wherein:

the control signal further comprises a carry signal provided to data driving chips; and

the look-up tables are selected in response to the carry signal.

9. The method of claim 7, wherein:

the control signal further comprises a port designating signal configured to designate a port through which the data clock signal is outputted; and

the look-up tables are selected in response to the port designating signal.

10. A driving unit of a display panel, the panel being divided into blocks according to distance from a light source to each of the blocks, the driving unit comprising:

a time controller configured to provide grayscale signals for the display panel and to calibrate the grayscale signals to form compensating signals, the compensating signals respectively corresponding to the blocks; and

a driving part configured to drive each block of the display panel using each corresponding compensating signal, to compensate for temperature differences in the blocks caused by heat from the light source.

11. The driving unit of claim 10, wherein the time controller comprises a grayscale compensating part configured to determine the compensating signals of an n-th frame using look-up tables, the look-up tables respectively corresponding to the blocks of the display panel, and “

n”

being a natural number.

12. The driving unit of claim 11, wherein the grayscale compensating part comprises:

a storing part configured to store a grayscale signal of an (n-1)-th frame;

look-up tables comprising information on the compensating signals of the n-th frame corresponding to the grayscale signals of the (n-1)-th frame and grayscale signals of the n-th frame;

a selecting part configured to select the look-up tables respectively corresponding to the blocks of the display panel; and

an output part configured to output the compensating signals of the n-th frame using each of the selected look-up tables.

13. The driving unit of claim 12, wherein the selecting part is configured to select the look-up tables in response to a control signal.

14. A display apparatus, comprising:

a light source configured to generate light;

a display panel configured to receive the light and comprising gate lines and data lines crossing each other, the display panel being divided into blocks according to distance from the light source to each of the blocks;

a time controller configured to provide grayscale signals for the display panel and to calibrate the grayscale signals to form compensating signals, the compensating signals respectively corresponding to the blocks; and

a driving part configured to drive each block of the display panel using each corresponding compensating signal, to compensate for temperature differences in the blocks caused by heat from the light source.

15. The display apparatus of claim 14, wherein the time controller comprises a grayscale compensating part to determine the compensating signals of an n-th frame using look-up tables, the look-up tables respectively corresponding to the blocks of the display panel, and “

n”

being a natural number.

16. The driving unit of claim 15, wherein the grayscale compensating part comprises:

a storing part configured to store a grayscale signal of an (n-1)-th frame;

look-up tables comprising information on the compensating signals of the n-th frame corresponding to the grayscale signal of the (n-1)-th frame and a grayscale signal of the n-th frame;

a selecting part configured to select the look-up tables; and

an output part configured to output the compensating signal of the n-th frame using each of the selected look-up tables.

17. The display apparatus of claim 16, wherein the selecting part is configured to select the look-up tables in response to a temperature signal of the display panel.

18. The display apparatus of claim 16, wherein the selecting part is configured to select the look-up tables in response to a control signal.

19. The display apparatus of claim 18, wherein:

the data driving part comprises data driving chips;

the control signal further comprises a carry signal provided to the data driving chips; and

the selecting part is configured to select the look-up tables in response to the carry signal.

20. The display apparatus of claim 18, wherein:

the control signal further comprises a port designating signal designating a port through which the data clock signal is outputted; and

the selecting part is configured to select the look-up tables in response to the port designating signal.

21. The display apparatus of claim 18, wherein the selecting part comprises a counter configured to count a number of pulses of the control signal.

22. The display apparatus of claim 21, wherein:

the light source is disposed adjacent to a side surface of the display panel and is substantially parallel with the gate lines; and

the selecting part is configured to select the look-up tables according to the number of pulses of a gate clock signal of the control signal.

23. The display apparatus of claim 21, wherein:

the light source is disposed adjacent to a side surface of the display panel and is substantially parallel with the data lines; and

the selecting part is configured to select the look-up tables according to the number of pulses of a data clock signal of the control signal.