Method for reducing pulsing on liquid crystal displays

• US 6,211,859 B1
• Filed: 02/24/1998
• Issued: 04/03/2001
• Est. Priority Date: 03/10/1997
• Status: Expired due to Fees

• Current Assignee: Intel Corporation
• Original Assignee: Chips and Technologies, Inc. (Intel Corporation)
• Inventors: Lin, Jian, Killebrew, Carrell R. Jr., Chang, Shih-hua
• Primary Examiner(s): Chow, Dennis-Doon
• Assistant Examiner(s): AWAD, AMR A
• Application Number:
  US09/028,828
• Time in Patent Office: 1,134 Days
• Field of Search: 345/147, 345/149, 345/152, 345/127, 345/89, 345/137, 345/138
• US Class Current: 345/596
• CPC Class Codes: G06T 3/40 Scaling of whole images or parts thereof, e.g. expanding or contracting
• 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 2320/0266 Reduction of sub-frame artefacts
• CPC Class Codes: G09G 2330/021 Power management, e.g. power saving
• CPC Class Codes: G09G 3/2018 by time modulation using two or more time intervals
• CPC Class Codes: G09G 3/3611 Control of matrices with row and column drivers

Abstract

A method for displaying grey-scale images at a desired grey scale resolution up to the visible limit on a display having a matrix of pixels, includes the steps of: defining a plurality of control matrices, each of said control matrices having a size and equal to the desired grey scale resolution of the display, each position in each of said control matrices corresponding to a specific pixel of said display; defining a super matrix, each position in said super matrix corresponding to one of said plurality of control matrices and having an assigned number in a range equal to the desired grey scale resolution; turning on a selected number of pixels within each of said control matrices based upon the grey scale value of the pixel, the orientation of the pixels turned on based on the value of a circular queue of size equal to said desired gray scale resolution; and adjusting the starting value of said circular queue for each of said control matrices based upon the number contained in the position of the super matrix corresponding to each control matrix and the gray scale value of the incoming pixel.

Claims

1. A method for displaying grey-scale images at a desired grey scale resolution on a display having a super matrix of matrices of pixels, comprising:

defining a plurality of control matrices, each of said control matrices having a size equal to the desired grey scale resolution of the display, each position in each of said control matrices corresponding to a specific pixel of said display;

defining a super matrix, each position in said super matrix corresponding to one of said plurality of control matrices and having an assigned number in a range equal to the desired grey scale resolution;

turning on a selected number of pixels within each of said control matrices based upon the grey scale value of the pixel, the orientation of the pixels turned on based on the value of a circular queue of size equal to said desired gray scale resolution; and

adjusting the starting value of said circular queue for each of said control matrices based upon the number contained in the position of the super matrix corresponding to each control matrix and the gray scale value of the pixel.

2. The method of claim 1 wherein said defining a plurality of control matrices includes assigning each position in each of said plurality of control matrices a value in a range equal to the desired gray scale resolution.

3. The method of claim 2 wherein said turning on includes comparing said control matrix value of each pixel in a frame of an image to be displayed on said display to an ON range and turning that pixel on if the control matrix value of that pixel is within said ON range, said ON range being equal in size to the grey scale value of that pixel and contained in a circular queue having a size equal to said desired grey scale resolution.

4. The method of claim 3 further including changing said ON range in said circular queue for each successive frame.

5. The method of claim 4 wherein changing said ON range in said circular queue for each successive frame comprises changing said range by an amount equal to the grey scale value of the pixel to be displayed.

6. The method of claim 4 wherein each grey scale value for each incoming pixel includes a plurality of color components, and wherein comparing said control matrix value of each pixel in a frame of an image to be displayed on said display to an ON range, turning that pixel on if the control matrix value of that pixel is within said ON range and changing the ON range in said circular queue for each successive frame by an amount sufficient to ensure that ON ranges for successive frames are non overlapping comprise separately performing these steps for each color component.

7. The method of claim 6 wherein the ON ranges for said plurality of color components are offset from one another in each frame.

8. A method for displaying grey-scale images at a desired grey scale resolution on a display having a super matrix of matrices of pixels, comprising:

defining a plurality of control matrices, each of said control matrices having a size equal to the desired grey scale resolution of the display, each position in each of said control matrices having an assigned value in the range of the desired gray scale resolution of the display, each position in each of said control matrices corresponding to a specific pixel of said display;

defining a super matrix, each position in said super matrix corresponding to one of said plurality of control matrices and having an assigned number in a range equal to the desired grey scale resolution;

turning on a selected number of pixels within each of said control matrices based upon the grey scale value of that pixel, the orientation of the pixels turned on based on whether each of said in each of said control matrices is within an ON range contained within a circular queue of size equal to said desired gray scale resolution, said ON range beginning at a value Rmin equal to (FG+S+Offset) modulo N and ending at a value Rmax equal to (Rmin+(G−

1)) modulo N, where F is the frame number, G is the gray scale value of the current pixel, S is the starting value of said circular queue and N is the desired gray scale resolution of the display; and

adjusting the starting value of said circular queue for each of said control matrices based upon the number contained in the position of the super matrix corresponding to each control matrix and the gray scale value of the pixel.

9. The method of claim 8 further including recalculating said ON range for a specific matrix if the gray scale value of the pixel changes.

10. The method of claim 8 wherein each grey scale value for each incoming pixel includes a plurality of color components, and wherein said turning on comprises separately performing said turning on for each color component.

11. The method of claim 10 wherein said offset is changed for each of said plurality of color components.

12. A method for displaying grey-scale images at a desired grey scale resolution on a display having a matrix of pixels, comprising:

defining a control matrix, said control matrix having a size equal to the desired grey scale resolution of the display, each position in said control matrix corresponding to a specific pixel of said display;

defining a super matrix, each position in said super matrix corresponding to one of said plurality of control matrices and having an assigned number in a range equal to the desired grey scale resolution;

turning on a selected number of pixels within said control matrix based upon the desired grey scale value, the orientation of the pixels turned on based upon value of a circular queue of size equal to said desired gray scale resolution; and

adjusting the starting value of the circular queue based upon the gray scale value of the incoming pixel.

13. The method of claim 12 wherein said defining includes assigning each position a value in a range equal to the desired gray scale resolution.

14. The method of claim 13 wherein said turning on includes comparing said control matrix value of each pixel in a frame of an image to be displayed on said display to an ON range and turning that pixel on if the control matrix value of that pixel is within said ON range, said ON range being equal to the grey scale value of that pixel and contained in a circular queue having a size equal to said desired grey scale resolution.

15. The method of claim 14 further including changing said ON range in said circular queue for each successive frame.

16. The method of claim 15 wherein said step of changing said ON range in said circular queue for each successive frame comprises changing said ON range by an amount equal to the grey scale value of the pixel to be displayed.

17. The method of claim 15 wherein each grey scale value for each incoming pixel includes a plurality of color components, and wherein comparing control matrix value of each pixel in a frame of an image to be displayed on said display to an ON range and turning that pixel on if the control matrix value of that pixel is within said ON range and changing said ON range in said circular queue for each successive frame comprises separately performing these procedures for each color component.

18. The method of claim 17 wherein said ON ranges for said plurality of color components are offset from one another in each frame.

19. A method for displaying grey-scale images at a desired grey scale resolution on a display having a matrix of pixels, comprising:

defining a control matrix, said control matrix having a size equal to the desired grey scale resolution of the display, each position in said control matrix corresponding to a specific pixel of said display;

turning on a selected number of pixels within each of said control matrices based upon the grey scale value of that pixel, the orientation of the pixels turned on based on whether each value in each of said control matrices is within an ON contained within a circular queue of size equal to said desired gray scale resolution, said ON range beginning at a value Rmin equal to (FG+S+Offset) modulo N and ending at a value Rmax equal to (Rmin+(G−

1)) modulo N, where F is the frame number, G is the gray scale value of the current pixel, S is the starting value of said circular queue and N is the desired gray scale resolution of the display; and

adjusting the starting value of the circular queue based upon the gray scale value of the incoming pixel.

20. The method of claim 19 further including recalculating said ON range for a specific matrix if the gray scale value of the pixel changes.

21. The method of claim 19 wherein each grey scale value for each incoming pixel includes a plurality of color components, and wherein the turning on comprises separately performing said turning on for each color component.

22. The method of claim 21 wherein said offset is changed for each of said plurality of color components.

23. A method for displaying grey-scale images at a desired grey scale resolution on a display having a super matrix of matrices of pixels, comprising the steps of:

defining a plurality of control matrices, each of said control matrices having a size equal to the desired grey scale resolution each position in each of said control matrices corresponding to a specific pixel of said display;

defining a super matrix, each position in said super matrix corresponding to one of said plurality of control matrices and having an assigned number in a range equal to the desired grey scale resolution;

turning on a selected number of pixels within each of said control matrices based upon the grey scale value of the pixel, the orientation of the pixels turned on based on the value of a circular queue of size equal to said desired gray scale resolution; and

adjusting the starting value of said circular queue for each of said control matrices based upon the number contained in the position of the super matrix corresponding to each control matrix and the gray scale value of the pixel.

24. The method of claim 23 wherein said defining a plurality of control matrices includes assigning each position in each of said plurality of control matrices a value in a range equal to the desired gray scale resolution.

25. The method of claim 24 wherein said turning on includes comparing said control matrix value of each pixel in a frame of an image to be displayed on said display to ON ranges and turning that pixel on if the control matrix value of that pixel is within an ON range, said ON range being equal to the grey scale value of that pixel and contained in a circular queue having a size equal to said desired grey scale resolution.

26. The method of claim 25 further including changing said ON range in said circular queue for each successive frame.

27. The method of claim 26 wherein changing said ON range in said circular queue for each successive frame comprises changing said range by an amount equal to the grey scale value of the pixel to be displayed.

28. The method of claim 26 wherein each grey scale value for each incoming pixel includes a plurality of color components, and wherein the comparing and turning on comprise separately performing these procedures for each color component.

29. The method of claim 28 wherein the ON ranges for said plurality of color components are offset from one another in each frame.

30. A method for displaying grey-scale images at a desired grey scale resolution on a display having a super matrix of matrices of pixels, comprising:

defining a plurality of control matrices, each of said control matrices having a size equal to the desired grey scale resolution, display each position in each of said control matrices containing a value in the range of the desired gray scale resolution of the display, each value corresponding to a specific pixel of said display;

defining a super matrix, each position in said super matrix corresponding to one of said plurality of control matrices and having an assigned number in a range equal to the desired grey scale resolution;

turning on a selected number of pixels within each of said control matrices based upon the grey scale value of that pixel, the orientation of the pixels turned on based on whether each of said values in each of said control matrices is within an ON range contained within a circular queue of size equal to said desired gray scale resolution, said ON range beginning at a value Rmin equal to (FG+S_m+S_s+Offset) modulo N and ending at a value Rmax equal to (Rmin+(G−

1)) modulo N, where F is the frame number, G is the gray scale value of the current pixel, S_m is the component of the starting value of said circular queue as affected by the position in said super matrix, S_s is the component of the starting value of said circular queue as affected by the gray scale value of the incoming pixel, and N is the desired gray scale resolution; and

adjusting Sm for each of said plurality of matrices based upon the number contained in the position of the super matrix corresponding to each control matrix, and adjusting Ss for each of said plurality of matrices based upon the gray scale value the incoming pixel.

31. The method of claim 30 further including recalculating said ON range for a specific matrix if the gray scale value of the pixel changes.

32. The method of claim 30 wherein each grey scale value for each incoming pixel includes a plurality of color components, and wherein the turning on step comprises separately performing the turning on for each color component.

33. The method of claim 32 wherein said offset is changed for each of said plurality of color components.