Changing display artifacts across frames

• US 8,947,413 B2
• Filed: 05/24/2011
• Issued: 02/03/2015
• Est. Priority Date: 05/24/2011
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Hotelling, Steven Porter, Yousefpor, Marduke, Bae, Hopil
• Primary Examiner(s): Olson, Jason
• Assistant Examiner(s): HOFFNER, LINH NGUYEN
• Application Number:
  US13/143,183
• Publication Number:
  US 20120299892A1
• Time in Patent Office: 1,351 Days
• Field of Search: 345/77, 345/209
• US Class Current: 345/209
• CPC Class Codes: G09G 2310/02 Addressing, scanning or driving the display screen or processing steps related thereto
• CPC Class Codes: G09G 2310/0218 with collection of electrodes in groups for n-dimensional addressing
• CPC Class Codes: G09G 2310/0297 Special arrangements with multiplexing or demultiplexing of display data in the drivers for data electrodes, in a pre-processing circuitry delivering display data to said drivers or in the matrix panel, e.g. multiplexing plural data signals to one D/A converter or demultiplexing the D/A converter output to multiple columns
• CPC Class Codes: G09G 2320/0209 Crosstalk reduction, i.e. to reduce direct or indirect influences of signals directed to a certain pixel of the displayed image on other pixels of said image, inclusive of influences affecting pixels in different frames or fields or sub-images which constitute a same image, e.g. left and right images of a stereoscopic display
• CPC Class Codes: G09G 2320/0233 Improving the luminance or brightness uniformity across the screen
• CPC Class Codes: G09G 3/3614 Control of polarity reversal in general
• CPC Class Codes: G09G 3/3648 using an active matrix G09G3/367 - G09G3/3696 take precedence
• CPC Class Codes: G09G 3/3677 suitable for active matrices only

Abstract

Displaying an image on a display screen is provided by periodically changing the scanning order in which rows of sub-pixels of the display screen are scanned. One scanning order can be selected to scan the rows in the update of a first image frame of the display, and then a different scanning order can be selected to scan the rows in the update of a second image frame. Particular scanning orders can be selected in order to reduce or eliminate the appearance of visual artifacts by changing the location of the visual artifacts across multiple image frames. For example, different scanning orders that result in visual artifacts at different positions on the display screen can be used, and the selection of scanning order can periodically change among the different scanning orders such that the position of the visual artifacts changes periodically during the updating of multiple image frames.

Claims

1. A method for displaying an image on a display screen, the display screen including a plurality of lines of sub-pixels, the method comprising:

updating a plurality of consecutive image frames of the display screen, each image frame being updated by scanning the plurality of lines of sub-pixels in a selected one of a plurality of different scanning orders, wherein updating the plurality of consecutive image frames includes periodically changing the selection of scanning order, wherein the plurality of different scanning orders comprises a first scanning order, a second scanning order, and a third scanning order;

wherein scanning the plurality of lines of sub-pixels in the first scanning order comprises scanning a first set of adjacent blocks, wherein the lines in each block in the first set are scanned in a first particular line order;

wherein scanning the plurality of lines of sub-pixels in the second scanning order comprises scanning a second set of adjacent blocks, wherein the lines in each block in the second set are scanned in a second particular line order, and wherein each block in the second set is shifted in a first direction by one or more lines from a corresponding block in the first set; and

wherein scanning the plurality of lines of sub-pixels in the third scanning order comprises scanning a third set of adjacent blocks, wherein the lines in each block in the third set are scanned in a third particular line order, and wherein each block in the third set is shifted in the first direction by one or more lines from a corresponding block in the second set.

2. The method of claim 1, wherein periodically changing the selection of scanning order includes changing the selection of scanning order every consecutive image frame.

3. The method of claim 1, wherein periodically changing the selection of scanning order includes selecting the second scanning order next after selecting the first scanning order.

4. The method of claim 3, wherein periodically changing the selection of scanning order includes selecting the third scanning order next after selecting the second scanning order.

5. The method of claim 1, wherein each of the first and second scanning orders includes a reordered M-line inversion scheme, and a first block of the first scanning order includes 2 M lines of sub-pixels.

6. The method of claim 5, wherein the reordered M-line inversion scheme is a reordered 4-line inversion scheme, the first scanning order is lines 1, 3, 5, and 7 of the first block, and the second scanning order is lines 2, 4, 6, and 8 of the first block.

7. The method of claim 1, wherein each of the first and second scanning orders includes a reordered 4-line inversion scheme, and the one or more lines each block is shifted is five lines.

8. The method of claim 1, wherein the one or more lines each block is shifted is one line.

9. The method of claim 8, wherein the plurality of different scanning orders includes 2 M different scanning orders, the different scanning orders including scanning different sets of pluralities of adjacent blocks of 2 M lines of sub-pixels, the lines in each block of 2 M lines are scanned in the predetermined line order, and the blocks in each different set are shifted by one line from the blocks in at least one other set.

10. The method of claim 1, wherein one or more blocks in the first set have the same size as one or more corresponding blocks in the second set.

11. The method of claim 1, wherein one or more blocks in the first set have a size different from one or more corresponding blocks in the second set.

12. An apparatus comprising:

a display screen including a plurality of lines of sub-pixels; and

a scanning system that updates a plurality of consecutive image frames of the display screen, each image frame being updated by scanning the plurality of lines of sub-pixels in a selected one of a plurality of different scanning orders, wherein updating the plurality of consecutive image frames includes periodically changing the selection of scanning order, wherein each scanning order of the plurality of scanning orders comprises a plurality of adjacent blocks of lines, and wherein each block in a first image frame of the plurality of consecutive image frames is shifted in a first direction by a predetermined number of lines to a corresponding block in a second image frame of the plurality of consecutive image frames, and each block in the second image frame of the plurality of consecutive image frames is shifted in the first direction by the predetermined number of lines to a corresponding block in a third image frame of the plurality of consecutive image frames.

13. The apparatus of claim 12, wherein periodically changing the selection of scanning order includes changing the selection of scanning order every consecutive image frame.

14. The apparatus of claim 12, wherein periodically changing the selection of scanning order comprises selecting a second scanning order associated with the second image frame next after selecting a first scanning order associated with the first image frame.

15. The apparatus of claim 14, wherein each of the first and second scanning orders includes a reordered M-line inversion scheme, and a first block of the first scanning order includes 2 M lines of sub-pixels.

16. The apparatus of claim 15, wherein the reordered M-line inversion scheme is a reordered 4-line inversion scheme, the first scanning order scans lines 1, 3, 5, and 7 in the first block, and the second scanning order is lines 2, 4, 6, and 8 in a shifted version of the first block.

17. The apparatus of claim 14, wherein each of the first and second scanning orders includes a reordered 4-line inversion scheme, and the predetermined number of lines is five lines.

18. The apparatus of claim 12, wherein periodically changing the selection of scanning order comprises selecting a third scanning order associated with the third image frame next after selecting the second scanning order associated with the second image frame.

19. The apparatus of claim 12, wherein the predetermined number of lines is one line.

20. The apparatus of claim 19, wherein the plurality of different scanning orders includes 2 M different scanning orders, the different scanning orders including scanning different sets of pluralities of adjacent blocks of 2 M lines of sub-pixels, the lines in each block of 2 M lines being scanned in the predetermined line order, and the blocks in each different set being shifted by one line from the blocks in at least one other set.

21. A non-transitory computer-readable storage medium storing computer-readable instructions that, when executed by a computing device, cause the device to perform a method of displaying an image on a display screen, the display screen including a plurality of lines of sub-pixels, the method comprising:

updating a plurality of consecutive image frames of the display screen, each image frame being updated by scanning the plurality of lines of sub-pixels in a selected one of a plurality of different scanning orders, wherein updating the plurality of consecutive image frames includes periodically changing the selection of scanning order, wherein each scanning order of the plurality of scanning orders comprises a plurality of adjacent blocks of lines, and wherein each block of a first scanning order associated with a first image frame is shifted in a first direction by a predetermined number of lines to a corresponding block of a second scanning order associated with a second image frame, and wherein each block of the second scanning order associated with the second image frame is shifted in the first direction by the predetermined number of lines to a corresponding block of a third scanning order associated with a third image frame.

22. The non-transitory computer-readable storage medium of claim 21, wherein periodically changing the selection of scanning order includes changing the selection of scanning order every consecutive image frame.

23. The non-transitory computer-readable storage medium of claim 21, wherein periodically changing the selection of scanning order comprises selecting the second scanning order next after selecting the first scanning order.