Image display device

• US 9,418,619 B2
• Filed: 06/20/2012
• Issued: 08/16/2016
• Est. Priority Date: 06/22/2011
• Status: Active Grant

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Nakagawa, Shinji, Miyata, Hidekazu, Furukawa, Hiroyuki, Yoshiyama, Kazuyoshi, Yoshida, Yasuhiro, Yanagi, Toshihiro, Nakano, Taketoshi, Yamato, Asahi, Inada, Ken
• Primary Examiner(s): Hoang, Phi
• Application Number:
  US14/127,521
• Publication Number:
  US 20140104301A1
• Time in Patent Office: 1,518 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: G02F 1/133514 Colour filters
• CPC Class Codes: G02F 2201/52 RGB geometrical arrangements
• 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 2320/0242 Compensation of deficiencies in the appearance of colours
• CPC Class Codes: G09G 2340/0457 Improvement of perceived resolution by subpixel rendering
• CPC Class Codes: G09G 2360/16 Calculation or use of calculated indices related to luminance levels in display data
• 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 5/02 characterised by the way in which colour is displayed details of colour display specific for CRTs G09G1/28; specific for flat matrix panels other than liquid crystal displays G09G3/2003; specific for liquid crystal displays G09G3/3607

Abstract

There is provided an image display device, in which a pixel includes sub-pixels of four or more colors that include a color in addition to the three primary colors, and which can display a high-quality image in which false colors or artifacts are suppressed. The image display device includes a pixel area in which a plurality of pixels P are arranged in a matrix shape, and each of the pixels P includes m (m is an integer which is equal to or greater than 4) sub-pixels SP. When it is assumed that the colors of the m sub-pixels SP included in one pixel are C1, C2, . . . , and Cm, the m sub-pixels SP which are sequentially arrayed from an arbitrary position include all of the colors of C1, C2, . . . , and Cm in both the vertical direction and the horizontal direction in the pixel area.

Claims

1. An image display device comprising:

a pixel area in which a plurality of pixels are arranged in a matrix shape, each of the pixels including m (m is an integer which is equal to or greater than

     4) sub-pixels; and

an image processing unit to which an image having a resolution higher than the number of pixels in the pixel area is input, and which assigns grayscale data of the input image to corresponding sub-pixels, wherein

when it is assumed that colors of m sub-pixels which are included in one pixel are represented as C1, C2, . . . , and Cm, the m sub-pixels which are sequentially arranged from an arbitrary position include all of the colors of C1, C2, . . . , and Cm in both a vertical direction and a horizontal direction in the pixel area; and

the C1, C2, . . . , and Cm include a color included in a first group and a color included in a second group having a higher brightness than the color included in the first group, and the sub-pixels with the color included in the second group are arranged at equal intervals in the pixel area.

2. The image display device according to claim 1,

wherein the C1, C2, . . . , and Cm include a color included in a first group and a color included in a second group having a higher brightness than the color included in the first group, and the sub-pixels with the color included in the second group are arranged such that three or more sub-pixels are not sequentially arranged in a diagonal direction in the pixel area.

3. The image display device according to claim 1, wherein the image processing unit:

determines whether or not the input image includes a high frequency signal in a specific direction; and

assigns the grayscale data of the input image to sub-pixels in order to maintain a resolution in the direction in which the input image is determined to include the high frequency signal.

4. The image display device according to claim 3, wherein the image processing unit includes a plurality of high-pass filters, and wherein, when assigning the greyscale data, the image processing unit:

calculates weight coefficients for the respective plurality of high-pass filters, based on outputs of the plurality of high-pass filters;

integrates the weight coefficients with the outputs from the respective plurality of high-pass filters; and

synthesizes results of integration.

5. The image display device according to claim 4,

wherein the image processing unit further includes a plurality of low-pass filters which are paired with the respective plurality of high-pass filters, and

wherein, when integrating the weight coefficients, the image processing unit integrates the weight coefficients with outputs from the respective plurality of high-pass filters and outputs from the respective plurality of low-pass filters.

6. The image display device according to claim 1,

wherein m is 4.

7. The image display device according to claim 1,

wherein m is 6.

8. The image display device according to claim 1,

wherein the colors of C1, C2, . . . , and Cm include three primary colors, that is, red, green, and blue.

9. The image display device according to claim 8,

wherein the colors of C1, C2, . . . , and Cm further include at least one color of cyan, magenta, yellow, and white.

10. The image display device according to claim 1, comprising:

a liquid crystal panel in which the pixel area is formed.

11. An image display device comprising:

a pixel area in which a plurality of pixels are arranged in a matrix shape, each of the pixels including m (m is an integer which is equal to or greater than

     4) sub-pixels; and

an image processing unit to which an image having a resolution higher than the number of pixels in the pixel area is input, and which assigns grayscale data of the input image to corresponding sub-pixels,

wherein, when it is assumed that colors of m sub-pixels which are included in one pixel are represented as C1, C2, . . . , and Cm, the m sub-pixels which are sequentially arranged from an arbitrary position include all of the colors of C1, C2, . . . , and Cm in both a vertical direction and a horizontal direction in the pixel area,

wherein the image processing unit;

determines whether or not the input image includes a high frequency signal in a specific direction; and

assigns the grayscale data of the input image to subpixels in order to maintain a resolution in the direction in which the input image is determined to include the high frequency signal,

wherein the image processing unit includes a plurality of high-pass filters, and

wherein, when assigning the greyscale data, the image processing unit;

calculates weight coefficients for the respective plurality of high-pass filters, based on outputs of the plurality of high-pass filters;

integrates the weight coefficients with the outputs from the respective plurality of high-pass filters; and

synthesizes results of integration.

12. The image display device according to claim 11,

wherein the C1, C2, . . . , and Cm include a color included in a first group and a color included in a second group having a higher brightness than the color included in the first group, and the sub-pixels with the color included in the second group are arranged at equal intervals in the pixel area.

13. The image display device according to claim 11,

wherein the C1, C2, . . . , and Cm include a color included in a first group and a color included in a second group having a higher brightness than the color included in the first group, and the sub-pixels with the color included in the second group are arranged such that three or more sub-pixels are not sequentially arranged in a diagonal direction in the pixel area.

14. The image display device according to claim 11,

wherein the image processing unit further includes a plurality of low-pass filters which are paired with the respective plurality of high-pass filters, and

wherein, when integrating the weight coefficients, the image processing unit integrates the weight coefficients with outputs from the respective plurality of high-pass filters and outputs from the respective plurality of low-pass filters.

15. The image display device according to claim 11,

wherein m is 4.

16. The image display device according to claim 11,

wherein m is 6.

17. The image display device according to claim 11,

wherein the colors of C1, C2, . . . , and Cm include three primary colors, that is, red, green, and blue.

18. The image display device according to claim 17,

wherein the colors of C1, C2, . . . , and Cm further include at least one color of cyan, magenta, yellow, and white.

19. The image display device according to claim 11,

further comprising:

a liquid crystal panel in which the pixel area is formed.