Method for providing grey scale images to the visible limit on liquid crystal displays

• US 6,034,663 A
• Filed: 03/10/1997
• Issued: 03/07/2000
• Est. Priority Date: 03/10/1997
• Status: Expired due to Term

• 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:
  US08/814,569
• Time in Patent Office: 1,093 Days
• Field of Search: 345/138, 345/147, 345/127, 345/149, 345/1.5, 345/152, 345/89, 345/137, 315/169.4
• 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 on a display having a matrix of pixels, comprises the steps of: defining a control matrix having a size smaller than the entire display and equal to the desired grey scale resolution of the display, each position in the control matrix having an address assigned such that unintended artifacts in the display are controlled; horizontally and vertically mapping the control matrix into the display such that each pixel in the matrix of pixels in the display corresponds to an address in a control matrix mapped into the display; comparing control matrix address of each pixel in a frame of an image to be displayed on the display to a range of address values and turning that pixel on if the grey scale value of that pixel is within the range of address values, the range of address values arranged in a circular queue and being equal to the grey scale value of that pixel; and shifting the range of address values in the circular queue for successive frame by an amount equal to the grey scale value of the pixel to be displayed.

Claims

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

defining one or more control matrices, said control matrices having a size equal to the desired grey scale resolution of the display, each position in said control matrices having an assigned value in a range with a size equal to the desired grey scale resolution;

horizontally and vertically mapping said control matrices into said display a number of times, such that each pixel in the matrix of pixels in the display corresponds to a location in one of the control matrices mapped into said display;

comparing the 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, the extent of 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; and

changing the ON range in said circular queue for each successive frame by an amount equal to the grey scale value of that pixel.

2. The method of claim 1 wherein the step of changing the ON range in said circular queue for each successive frame comprises the step of changing said ON range by an amount equal to the grey scale value of the pixel to be displayed.

3. The method of claim 1 wherein each grey scale value for each incoming pixel includes a plurality of color components, and wherein the step of 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 and the step of changing the ON range in said circular queue for each successive frame by an amount sufficient to ensure that ON ranges successive frames are non overlapping comprises separately performing these steps for each color component.

4. The method of claim 3 wherein the ON ranges for said plurality of color components are offset from one another in each frame.

5. The method of claim 3 wherein said plurality of color components comprises a red, a green, and a blue component.

6. The method of claim 4 wherein said plurality of color components comprises a red, a green, and a blue component.

15. The method of claim 1, wherein said defining step includes placing values in said one or more matrices without placing two consecutive values next to each other in the horizontal, vertical, or diagonal directions.

16. The method of claim 1, wherein said defining step includes placing values in said one or more matrices without placing consecutive values on the same row, column, or diagonal.

17. The method of claim 1, wherein said defining step includes placing values in said one or more matrices such as the distribution of values within each matrix is approximately even from top to bottom and left to right.

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

defining one or more control matrices, said control matrices having a size at least equal to the desired grey scale resolution of the display, each position in said control matrices having an assigned value in a range with a size equal to the desired grey scale resolution;

horizontally and vertically mapping said control matrices into said display a number of times such that each pixel in the matrix of pixels in the display corresponds to a location in one of the control matrices mapped into said display; and

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, the extent of said ON range being equal to the grey scale value of that pixel and being contained in a circular queue having a size equal to said desired grey scale resolution, said ON range for each frame F beginning at a value Rmin equal to (FG+Offset) modulo N and ending at a value Rmax equal to (Rmin+(G-1)) modulo N, where G is the grey scale value of the current pixel, F is the frame number, and N is the desired grey scale resolution.

8. The method of claim 7 wherein each grey scale value for each incoming pixel includes a plurality of color components, and wherein the step of comparing the 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 the step of 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 comprises separately performing these steps for each color component.

9. The method of claim 8 wherein the ON range for said plurality of color components are offset from one another in each frame.

10. The method of claim 8 wherein said plurality of color components comprises a red, a green, and a blue component.

11. The method of claim 9 wherein said plurality of color components comprises a red, a green, and a blue component.

18. The method of claim 7, wherein said defining step includes placing values in said one or more matrices without placing two consecutive values next to each other in the horizontal, vertical, or diagonal directions.

19. The method of claim 7, wherein said defining step includes placing values in said one or more matrices without placing consecutive values on the same row, column, or diagonal.

20. The method of claim 7, wherein said defining step includes placing values in said one or more matrices such as the distribution of values within each matrix is approximately even from top to bottom and left to right.

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

defining one or more control matrices, said control matrices having a size equal to at least the desired grey scale resolution of the display, each position in said control matrices having an assigned value in a range equal to the desired grey scale resolution;

horizontally and vertically mapping said control matrices into said display such that each pixel in the matrix of pixels in the display corresponds to a location in one of the control matrices mapped into said display;

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, the extent of 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; and

changing the ON range in said circular queue for each successive frame by an amount equal to the grey scale value of that pixel.

13. The method of claim 12 wherein the step of horizontally and vertically mapping said control matrix into said display includes the step of offsetting the column order of matrices in vertically adjacent mappings of said control matrix.

21. The method of claim 12, wherein said defining step includes placing values in said one or more matrices without placing two consecutive values next to each other in the horizontal, vertical, or diagonal directions.

22. The method of claim 12, wherein said defining step includes placing values in said one or more matrices without placing consecutive values on the same row, column, or diagonal.

23. The method of claim 12, wherein said defining step includes placing values in said one or more matrices such as the distribution of values within each matrix is approximately even from top to bottom and left to right.

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

defining one or more control matrices, said control matrices having a size equal to at least the desired grey scale resolution of the display, each position in said control matrices having an assigned value in a range equal to the desired grey scale resolution;

horizontally and vertically mapping said control matrices into said display such that each pixel in the matrix of pixels in the display corresponds to a location in one of the control matrices mapped into said display, offsetting the column order of matrices in vertically adjacent mappings of said control matrix;

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, the extent of 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; and

changing the ON range in said circular queue for each successive frame by an amount equal to the grey scale value of that pixel.