Liquid crystal display device achieving predetermined color temperature while preventing a shift in color tone by correcting blue luminance

1. A liquid crystal display device, comprising:

a liquid crystal display panel which includes a pixel defined by at least three sub-pixels including a blue sub-pixel;

a backlight arranged to emit, toward the liquid crystal display panel, light that brings a color temperature to a predetermined level when the pixel displays white; and

a color tone correction section arranged to correct a color tone of a color displayed by the pixel; wherein

when the pixel displays a color containing at least one predetermined color component that is other than a white component and a blue component, the color tone correction section makes a correction to set a luminance of the blue sub-pixel lower than an original luminance; and

the luminance of the blue sub-pixel remains uncorrected whenever the color displayed by the pixel includes only the white component.

2. The liquid crystal display device according to claim 1 , wherein the at least one predetermined color component is a magenta component or a cyan component.

3. The liquid crystal display device according to claim 1 , wherein, when the pixel displays a color that contains only the blue component, or a color that contains only the white component and the blue component, the color tone correction section makes a correction to set the luminance of the blue sub-pixel lower than the original luminance.

4. The liquid crystal display device according to claim 1 , wherein, when the pixel displays a color that contains only the blue component, or a color that contains only the white component and the blue component, the color tone correction section does not make a correction on the luminance of the blue sub-pixel and the luminance of the blue sub-pixel is equal to the original luminance.

5. The liquid crystal display device according to claim 1 , wherein a maximum luminance of the blue sub-pixel that is set when the pixel displays an arbitrary color containing the at least one predetermined color component is lower than the luminance of the blue sub-pixel that is set when the pixel displays at least one of white and blue.

6. The liquid crystal display device according to claim 1 , wherein the color tone correction section creates a corrected image signal that indicates luminances to be actually presented by the at least three sub-pixels, from an image signal that indicates original luminances of a red sub-pixel, a green sub-pixel, and the blue sub-pixel in a pixel that is formed only of the red sub-pixel, the green sub-pixel, and the blue sub-pixel.

7. The liquid crystal display device according to claim 6 , wherein the color tone correction section includes:

a color component extracting unit arranged to extract a color component from a color of the pixel that is indicated by the image signal; and

a signal synthesizing unit which is arranged to create, based on the original luminance of the blue sub-pixel and the color component, the corrected image signal in a manner that makes the luminance to be actually presented by the blue sub-pixel lower than the original luminance.

8. The liquid crystal display device according to claim 1 , wherein the at least three sub-pixels include a red sub-pixel and a green sub-pixel.

9. The liquid crystal display device according to claim 8 , wherein the at least three sub-pixels further include a yellow sub-pixel.

10. The liquid crystal display device according to claim 9 , wherein the color tone correction section sets a luminance of the yellow sub-pixel to a predetermined value.

11. The liquid crystal display device according to claim 8 , wherein, when the pixel displays a color which is free of a yellow component and which contains at least one color component other than the yellow component, the color tone correction section makes a correction to set the luminance of the blue sub-pixel lower than the original luminance.

12. The liquid crystal display device according to claim 9 , wherein the at least three sub-pixels further include a cyan sub-pixel.

13. The liquid crystal display device according to claim 12 , wherein, when the pixel displays a color which is free of the yellow component and a cyan component and which contains at least one color component other than the yellow component and the cyan component, the color tone correction section makes a correction to set the luminance of the blue sub-pixel lower than the original luminance.

14. A liquid crystal display device comprising a pixel that is defined by at least three sub-pixels including a blue sub-pixel, wherein

a maximum luminance of the blue sub-pixel that is set when the pixel displays an arbitrary color containing at least one predetermined color component that is other than a white component and a blue component is lower than a luminance of the blue sub-pixel that is set when the pixel displays at least one of white and blue;

the luminance of the blue sub-pixel is corrected when the pixel displays a color containing the at least one predetermined color component that is other than the white component and the blue component; and

the luminance of the blue sub-pixel remains uncorrected whenever the color displayed by the pixel includes only the white component.

15. The liquid crystal display device according to claim 14 , wherein the at least one predetermined color component is a magenta component or a cyan component.

16. The liquid crystal display device according to claim 14 , wherein the at least three sub-pixels include a red sub-pixel and a green sub-pixel.

17. The liquid crystal display device according to claim 16 , wherein the at least three sub-pixels further include a yellow sub-pixel.

18. The liquid crystal display device according to claim 17 , wherein the at least three sub-pixels further include a cyan sub-pixel.

19. A liquid crystal display device comprising a pixel containing a red sub-pixel, a green sub-pixel, and a blue sub-pixel, wherein

a luminance of the blue sub-pixel that is set when the pixel displays magenta and a luminance of the blue sub-pixel that is set when the pixel displays cyan are lower than a luminance of the blue sub-pixel that is set when the pixel displays white;

the luminance of the blue sub-pixel is corrected when the pixel displays a color containing at least one predetermined color component that is other than a white component and a blue component; and

the luminance of the blue sub-pixel remains uncorrected whenever the color displayed by the pixel includes only the white component.

20. The liquid crystal display device according to claim 19 , wherein the pixel further includes a yellow sub-pixel.

21. The liquid crystal display device according to claim 20 , wherein the pixel further includes a cyan sub-pixel.