Color flat panel display sub-pixel arrangements and layouts for sub-pixel rendering with increased modulation transfer function response

• US 20030128225A1
• Filed: 10/22/2002
• Published: 07/10/2003
• Est. Priority Date: 01/07/2002
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Higgins, Michael Francis, Credelle, Thomas Lloyd, Brown Elliott, Candice Hellen
• Granted Patent: US 7,492,379 B2
• Time in Patent Office: Days
• US Class Current: 345/694
• CPC Class Codes: G02F 1/133514 Colour filters
• CPC Class Codes: G02F 1/134345 Subdivided pixels, e.g. for grey scale or redundancy
• CPC Class Codes: G09G 2300/0452 Details of colour pixel setup, e.g. pixel composed of a red, a blue and two green components
• CPC Class Codes: G09G 2340/0457 Improvement of perceived resolution by subpixel rendering
• CPC Class Codes: G09G 3/2003 Display of colours specific for liquid crystal displays G09G3/3607
• CPC Class Codes: G09G 3/3607 for displaying colours or for displaying grey scales with a specific pixel layout, e.g. using sub-pixels display of colours in flat matrix panels other than liquid crystal displays G09G3/2003; grey scales specific for television H04N3/127
• CPC Class Codes: G09G 3/3614 Control of polarity reversal in general

Abstract

Various embodiments of a sub-pixel octal grouping are disclosed. The octal grouping may comprise three-color sub-pixels with one colored sub-pixel comprising twice the number of positions within the octal sub-pixel grouping as the other two colored sub-pixels. Various embodiments for performing sub-pixel rendering on the sub-pixel groupings are disclosed.

Claims

1. A display comprising a plurality of a sub-pixel group;

said sub-pixel group further comprising eight sub-pixels;

wherein each said sub-pixel is one of a first color sub-pixel, a second color sub-pixel and a third color sub-pixel;

wherein said sub-pixel group further comprises four sub-pixels of said first color, two sub-pixels of said second color and two sub-pixels of said third color;

wherein further said sub-pixels of said second color and said sub-pixels of said third color form substantially a checkerboard pattern.

2. The display as recited in claim 1 wherein said first color comprises a green color and each said second color and said third color comprises one of a red color and a blue color, respectively.

3. The display as recited in claim 1 wherein said first color comprises a red color and each said second color and said third color is one of a green color and a blue color, respectively.

4. The display as recited in claim 1 wherein said sub-pixels of said first color comprises a smaller area than said sub-pixels of said second color and said third color.

5. The display as recited in claim 1 where said sub-pixel group further comprises substantially two rows and four columns of sub-pixels;

and

wherein further a first set of two non-adjacent columns comprise four sub-pixels of said first color and a second set of two non-adjacent columns comprise two sub-pixels of said second color and two sub-pixels of said third color.

6. The display as recited in claim 5 wherein said two non-adjacent columns comprising four sub-pixels of said first color are offset vertically from said two non-adjacent columns comprise two sub-pixels of said second color and two sub-pixels of said third color.

7. The display as recited in claim 1 wherein said sub-pixels of said first color are interspersed said substantially formed checkerboard pattern of sub-pixels of said second color and said third color.

8. The display as recited in claim 1 wherein said display is an active matrix liquid crystal display.

9. The display as recited in claim 8 wherein said display applies a dot inversion scheme for driving the sub-pixels in each sub-pixel group.

10. The display as recited in claim 9 wherein said dot inversion scheme is 1×

1 dot inversion.

11. The display as recited in claim 9 wherein said dot inversion scheme is 2×

1 dot inversion.

12. In a display, said display comprising a plurality of a sub-pixel group;

said sub-pixel group further comprising eight sub-pixels;

wherein each said sub-pixel is one of a first color sub-pixel, a second color sub-pixel and a third color sub-pixel;

wherein said sub-pixel group further comprises four sub-pixels of said first color, two sub-pixels of said second color and two sub-pixels of said third color;

wherein further said sub-pixels of said second color and said sub-pixels of said third color form substantially a checkerboard pattern;

a method of converting a source pixel data of a first format for rendering onto said display comprising;

determining implied sample areas for each data point of incoming three-color pixel data;

determining the resample area for each color sub-pixel in the display;

forming a set of coefficients for each the resample area, said coefficients comprising fractions whose denominators are a function of the resample area and the numerators are a function of an area of each the implied sample areas that may partially overlap said resample areas;

multiplying the incoming pixel data for each implied sample area by the coefficient resulting in a product; and

adding each the product to obtain luminance values for each resample area.

13. The method as recited in claim 12 wherein determining the resample area further comprises:

determining a phase relationship between the resample area for each color sub-pixel.

14. The methods as recited in claim 13 wherein determining a phase relationship further comprises:

positioning resample points for each said color resample areas such that the resample points for said second color and said third color substantially overlay the resample points for said first color.

15. The method as recited in claim 12 wherein said first color is green, and said second and third colors are red and blue respectively;

wherein said green color plane conversion comprises a unity filter and the red and blue color plane use a 3×

3 filter coefficient matrix.

16. The method as recited in claim 15 wherein said green color plane comprises a unity filter centered to match substantially an input pixel by adjusting said filter with respect to the sub-pixel grid.

17. In a display, said display comprising a plurality of a sub-pixel group;

said sub-pixel group further comprising eight sub-pixels;

wherein each said sub-pixel is one of a first color sub-pixel, a second color sub-pixel and a third color sub-pixel;

wherein said sub-pixel group further comprises four sub-pixels of said first color, two sub-pixels of said second color and two sub-pixels of said third color;

wherein further said sub-pixels of said second color and said sub-pixels of said third color form substantially a checkerboard pattern;

a method of converting a source pixel data of a first format for rendering onto said display comprising;

inputting a set of color image data;

testing the input data for a plurality of conditions; and

taking appropriate actions in response to the outcome of said testing of the input data.

18. The method as recited in claim 17 wherein said set of color image input data comprises a sample of a 1×

3 matrix of input data.

19. The method as recited in claim 17 wherein said set of color image input data comprises a sample of a 1×

2 matrix of input data.

20. The method as recited in claim 17 wherein testing the input data for a plurality of conditions further comprises:

testing for the detection of a high contrast feature in the input data.

21. The method as recited in claim 20 wherein said high contrast feature comprises one of a group, said group comprising an edge, a line, and a dot.

22. The method as recited in claim 17 wherein taking appropriate actions in response to the outcome of said testing of the input data further comprises:

substitute a new color data value for the current color data value.

23. The method as recited in claim 17 wherein taking appropriate actions in response to the outcome of said testing of the input data further comprises:

apply gamma correction to the current color data value.

24. The method as recited in claim 17 wherein taking appropriate actions in response to the outcome of said testing of the input data further comprises:

apply new sub-pixel rendering filter coefficients to the input data.

25. A system comprising:

a display, said display comprising a plurality of a sub-pixel group;

said sub-pixel group further comprising eight sub-pixels;

wherein each said sub-pixel is one of a first color sub-pixel, a second color sub-pixel and a third color sub-pixel;

wherein said sub-pixel group further comprises four sub-pixels of said first color, two sub-pixels of said second color and two sub-pixels of said third color;

wherein further said sub-pixels of said second color and said sub-pixels of said third color form substantially a checkerboard pattern; and

means for subpixel rendering input image data.

26. The system as recited in claim 25 wherein said means for subpixel rendering input data further comprises:

means for inputting a set of color image data;

means for testing the input data for a plurality of conditions; and

means for taking appropriate actions in response to the outcome of said testing of the input data.

27. The system as recited in claim 26 wherein said set of color image input data comprises a sample of a 1×

3 matrix of input data.

28. The system as recited in claim 26 wherein said set of color image input data comprises a sample of a 1×

2 matrix of input data.

29. The system as recited in claim 26 wherein said means for testing the input data for a plurality of conditions further comprises:

means for testing for the detection of a high contrast feature in the input data.

30. The system as recited in claim 29 wherein said high contrast feature comprises one of a group, said group comprising an edge, a line, and a dot.

31. The system as recited in claim 26 wherein means for taking appropriate actions in response to the outcome of said testing of the input data further comprises:

means for substituting a new color data value for the current color data value.

32. The system as recited in claim 26 wherein means for taking appropriate actions in response to the outcome of said testing of the input data further comprises:

means for applying gamma correction to the current color data value.

33. The system as recited in claim 26 wherein means for taking appropriate actions in response to the outcome of said testing of the input data further comprises:

means for applying new sub-pixel rendering filter coefficients to the input data.

34. The system as recited in claim 25 wherein said means for subpixel rendering input data further comprises:

means for determining implied sample areas for each data point of incoming three-color pixel data;

means for determining the resample area for each color sub-pixel in the

means for forming a set of coefficients for each the resample area, said coefficients comprising fractions whose denominators are a function of the resample area and the numerators are a function of an area of each the implied sample areas that may partially overlap said resample areas;

means for multiplying the incoming pixel data for each implied sample area by the coefficient resulting in a product; and

means for adding each the product to obtain luminance values for each resample area.

35. The system as recited in claim 34 wherein means for determining the resample area further comprises:

means for determining a phase relationship between the resample area for each color sub-pixel.

36. The system as recited in claim 35 wherein means for determining a phase relationship further comprises:

means for positioning resample points for each said color resample areas such that the resample points for said second color and said third color substantially overlay the resample points for said first color.

37. The system as recited in claim 34 wherein said first color is green, and said second and third colors are red and blue respectively;

wherein said green color plane conversion comprises a unity filter and the red and blue color plane use a 3×

3 filter coefficient matrix.

38. The system as recited in claim 37 wherein said green color plane comprises a unity filter centered to match substantially an input pixel by adjusting said filter with respect to the sub-pixel grid.