System and method for correcting defective pixels of a display device

• US 7,453,449 B2
• Filed: 09/23/2004
• Issued: 11/18/2008
• Est. Priority Date: 09/23/2004
• Status: Expired due to Fees

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Tretter, Daniel R., Damera-Venkata, Niranjan, Ulichney, Robert A.
• Primary Examiner(s): Hjerpe; Richard
• Assistant Examiner(s): Abdin; Shaheda A
• Application Number:
  US10/947,762
• Publication Number:
  US 20060061604A1
• Time in Patent Office: 1,517 Days
• Field of Search: 345/84.89, 345/690, 345/691, 345/694
• US Class Current: 345/204
• CPC Class Codes: G09G 2330/10 Dealing with defective pixels
• CPC Class Codes: G09G 2340/0407 Resolution change, inclusive of the use of different resolutions for different screen areas
• CPC Class Codes: G09G 3/007 Use of pixel shift techniques, e.g. by mechanical shift of the physical pixels or by optical shift of the perceived pixels
• 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 3/2011 by amplitude modulation
• CPC Class Codes: H04N 9/646 for image enhancement, e.g. vertical detail restoration, cross-colour elimination, contour correction, chrominance trapping filters

Abstract

A method of displaying an image with a display device having a plurality of defective pixels is provided. The method comprises selecting an offset between a first sub-frame and a second sub-frame using information associated with the plurality of defective pixels, generating the first sub-frame and the second sub-frame using image data for the image, adjusting a first sub-frame pixel value in the first sub-frame associated with one of the plurality of defective pixels, and alternating between displaying the first sub-frame in a first position and displaying the second sub-frame in a second position, the second position displaced from the first position by an amount defined by the offset.

Claims

1. A method of displaying an image with a display device having a plurality of defective pixels, the method comprising:

identifying first and second numbers of stuck-on-stuck pixels caused by the plurality of defective pixels for first and second offsets, respectively, between a first sub-frame and a second sub-frame;

selecting the first offset as a selected offset in response to the first number being less than the second number and the second offset as the selected offset in response to the second number being less than the first number;

generating the first sub-frame and the second sub-frame using image data for the image;

adjusting a first sub-frame pixel value in the first sub-frame associated with one of the plurality of defective pixels; and

alternating between displaying the first sub-frame in a first position and displaying the second sub-frame in a second position, the second position displaced from the first position by an amount defined by the selected offset.

2. The method of claim 1 further comprising:

selecting the first offset as the selected offset in response to the first number being equal to the second number and the first offset being associated with a lower number of edge pixels than the second offset.

3. The method of claim 1 further comprising:

adjusting the first sub-frame pixel value in the first sub-frame by increasing the first sub-frame pixel value in response to the one of the plurality of defective pixels comprising a stuck-off pixel.

4. The method of claim 1 further comprising:

adjusting the first sub-frame pixel value in the first sub-frame by decreasing the first sub-frame pixel value in response to the one of the plurality of defective pixels comprising a stuck-on pixel.

5. The method of claim 1 further comprising:

adjusting a second sub-frame pixel value in the second sub-frame associated with the one of the plurality of defective pixels.

6. The method of claim 5 further comprising:

adjusting the second sub-frame pixel value in the second sub-frame by increasing the second sub-frame pixel value in response to the one of the plurality of defective pixels comprising a stuck-off pixel.

7. The method of claim 5 further comprising:

adjusting the second sub-frame pixel value in the second sub-frame by decreasing the second sub-frame pixel value in response to the one of the plurality of defective pixels comprising a stuck-on pixel.

8. The method of claim 1 further comprising:

adjusting a second sub-frame pixel value in the first sub-frame associated with an edge pixel.

9. The method of claim 8 further comprising:

adjusting the second sub-frame pixel value in the first sub-frame by increasing the second sub-frame pixel value.

10. The method of claim 1 wherein the selected offset comprises a horizontal offset and a vertical offset.

11. The method of claim 10 wherein the horizontal offset is equal to n pixels where n is an integer, and wherein the vertical offset is equal to m pixels where m is an integer.

12. A system for displaying an image, the system comprising:

an image processing unit; and

a display device having a plurality of defective pixels;

wherein the image processing unit is configured to determine a selected offset from one of a plurality of possible offsets between a first sub-frame and a second sub-frame with a lowest number of stuck-on-stuck pixels caused by the plurality of defective pixels, wherein the image processing unit is configured to generate a first sub-frame and a second sub-frame using image data for the image, information associated with the plurality of defective pixels, and the selected offset, wherein the display device is configured to alternately display the first sub-frame in a first position and display the second sub-frame in a second position, and wherein the second position is displaced from the first position according to the selected offset.

13. The system of claim 12 wherein the image processing unit is configured to generate a third sub-frame and a fourth sub-frame using the image data, information associated with the plurality of defective pixels, and the selected offset, wherein the display device is configured to alternately display the third sub-frame in a third position and display the fourth sub-frame in a fourth position, and wherein the third position and the fourth position are displaced from the first position according to the selected offset.

14. The system of claim 12 wherein the image processing unit is configured to select the selected offset by determining a number of stuck-on-stuck pixels for each of the plurality of possible offsets.

15. The system of claim 14 wherein the selected offset as the one of the plurality of possible offsets with a lowest number of edge pixels in response to at least two of the plurality of possible offsets being associated with the lowest number of stuck-on-stuck pixels.

16. The system of claim 12 wherein the image processing unit is configured to adjust a first sub-frame pixel value in the first sub-frame by increasing the first sub-frame pixel value in response to one of the plurality of defective pixels associated with the first sub-frame pixel value comprising a stuck-off pixel.

17. The system of claim 16 wherein the image processing unit is configured to adjust a second sub-frame pixel value in the second sub-frame by increasing the second sub-frame pixel value in response to one of the plurality of defective pixels associated with the second sub-frame pixel value comprising a stuck-off pixel.

18. The system of claim 12 wherein the image processing unit is configured to adjust a first sub-frame pixel value in the first sub-frame by decreasing the first sub-frame pixel value in response to one of the plurality of defective pixels associated with the first sub-frame pixel value comprising a stuck-on pixel.

19. The system of claim 18 wherein the image processing unit is configured to adjust a second sub-frame pixel value in the second sub-frame by decreasing the second sub-frame pixel value in response to one of the plurality of defective pixels associated with the second sub-frame pixel value comprising a stuck-on pixel.

20. The system of claim 12 wherein the image processing unit is configured to adjust a first sub-frame pixel value in the second sub-frame in response to the first sub-frame pixel value being associated with an edge pixel.

21. The system of claim 20 wherein the image processing unit is configured to adjust the first sub-frame pixel value in the second sub-frame by increasing the first sub-frame pixel value in response to the first sub-frame pixel value being associated with the edge pixel.

22. The system of claim 12 wherein the selected offset comprises a horizontal offset and a vertical offset, wherein the horizontal offset is equal to n pixels where n is an integer, and wherein the vertical offset is equal to m pixels where m is an integer.

23. A system for displaying an image using a display device having a plurality of detective pixels, the system comprising:

means for selecting a selected offset from one of a plurality of possible offsets between a first sub-frame and a second sub-frame with a lowest number of stuck-on-stuck pixels;

means for generating the first sub-frame and the second sub-frame using image data for the image, the information associated with the plurality of detective pixels, and the selected offset; and

means for sequentially displaying the first sub-frame in a first position and displaying the second sub-frame in a second position which is displaced from the first position according to the selected offset.

24. The system of claim 23 wherein the selected offset comprises a horizontal offset and a vertical offset, wherein the horizontal offset is equal to n pixels where n is an integer, and wherein the vertical offset is equal to m pixels where m is an integer.

25. A computer-readable medium storing instructions readable and executable by a computer for causing the computer to perform a method of generating a first sub-frame and a second sub-frame for display at spatially offset positions defined by a selected offset by a display device having a plurality of defective pixels to generate the appearance of an image, comprising:

determining the selected offset as one of a plurality of possible offsets with a lowest number of stuck-on-stuck pixels caused by the plurality of defective pixels;

generating the first sub-frame including adjusting a first plurality sub-frame pixel values of the first sub-frame associated with the plurality of defective pixels; and

generating the second sub-frame including adjusting a second plurality sub-frame pixel values of the second sub-frame associated with the plurality of defective pixels.

26. The computer-readable medium of claim 25 storing instructions readable and executable by the computer for causing the computer to perform the method further comprising:

identifying the first plurality sub-frame pixel values in accordance with the plurality of defective pixels and the selected offset; and

identifying the second plurality sub-frame pixel values in accordance with the plurality of defective pixels and the selected offset.

27. The computer-readable medium of claim 25 storing instructions readable and executable by the computer for causing the computer to perform the method further comprising:

determining a number of stuck-on-stuck pixels for each of the plurality of possible offsets.

28. The computer-readable medium of claim 27 storing instructions readable and executable by the computer for causing the computer to perform the method further comprising:

determining the selected offset as the one of the plurality of possible offsets with a lowest number of edge pixels in response to at least two of the plurality of possible offsets being associated with the lowest number of stuck-on-stuck pixels.

29. The computer-readable medium of claim 25 wherein the selected offset comprises a horizontal offset and a vertical offset, wherein the horizontal offset is equal to n pixels where n is an integer, and wherein the vertical offset is equal to m pixels where m is an integer.