DISPLAY DEVICE

• US 20100321414A1
• Filed: 09/26/2008
• Published: 12/23/2010
• Est. Priority Date: 09/27/2007
• Status: Abandoned Application

• Current Assignee: Kohji Fujiwara, Takao Muroi, Takayuki Murai
• Original Assignee: Kohji Fujiwara, Takao Muroi, Takayuki Murai
• Inventors: Fujiwara, Kohji, Muroi, Takao, Murai, Takayuki
• Application Number:
  US12/677,076
• Publication Number:
  US 20100321414A1
• Time in Patent Office: Days
• US Class Current: 345/690
• 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 2320/0242 Compensation of deficiencies in the appearance of colours
• CPC Class Codes: G09G 2320/0285 using tables for spatial correction of display data
• CPC Class Codes: G09G 2320/0646 Modulation of illumination source brightness and image signal correlated to each other
• CPC Class Codes: G09G 2320/0666 for control of colour parameters, e.g. colour temperature
• CPC Class Codes: G09G 2360/16 Calculation or use of calculated indices related to luminance levels in display data
• CPC Class Codes: G09G 3/3413 Details of control of colour illumination sources
• CPC Class Codes: G09G 3/3426 the different display panel areas being distributed in two dimensions, e.g. matrix

Abstract

It is an object of the present invention to provide a display device that can improve the color reproductivity on a displayed image and improve the display quality. A liquid crystal display device (1) is provided with a backlight device (3) and a liquid crystal panel (2) configured to have capability of color display of information by using illumination light from the backlight device (3). The backlight device (3) has a plurality of illumination areas (Ha) with respect to a plurality of display areas provided on the liquid crystal panel (2), and light-emitting diodes (light sources) of RGB (8r, 8g, 8b) mixable with white light are provided for each illumination area (Ha). Its control part is provided with a backlight control part that determines for each of the light sources a luminance value of light emitted from each of the plural illumination areas (Ha) to a corresponding display area by using an inputted picture signal and that controls the drive of a backlight part, so that an area active backlight drive is carried out. The light-emitting diodes (light sources) of RGB (8r, 8g, 8b) have offset luminances that are set independently from each other.

Claims

1. A display device comprising:

a backlight part that has light sources; and

a display part that has a plurality of pixels and that is configured to be capable of color display of information by using illumination light from the backlight part,

the display device further comprising;

a plurality of illumination areas that are provided on the backlight part and that allows light from the light sources to enter respectively a plurality of display areas provided on the display part; and

a control part that controls drive of the backlight part and drive of the display part by using an inputted picture signal,

the backlight part is provided with light sources of at least two colors mixable with white light for each of the illumination areas; and

offset luminances of the light sources of at least two colors are set independently from each other.

2. The display device according to claim 1, wherein

the display part is provided with a color filter for each of the pixels,

the control part is provided with a backlight control part that determines for each of the light sources a luminance value of light emitted from each of the plural illumination areas to a corresponding display area by using the inputted picture signal and controls the drive of the backlight part, and

the backlight control part is provided with a luminance determining part that corrects and determines a luminance value determined for each of the light sources by using a correction coefficient preset on the basis of a predetermined CF property of the color filter and a predetermined emission property of the light sources.

3. The display device according to claim 1, wherein

light-emitting components that respectively emit light of red, green and blue are used as the light sources;

the display part is provided with a color filter for each of the pixels;

the control part is provided with a backlight control part that determines for each of the light sources the luminance value of light emitted from each of the illumination areas to a corresponding display area by using an inputted picture signal and controls the drive of the backlight part,

the backlight control part is provided with a luminance determining part that compares the determined luminance value of green and the determined luminance value of blue by using the inputted picture signal, and determines the larger luminance value as the luminance value of green and as the luminance value of blue.

4. The display device according to claim 2, wherein the control part is provided with a display control part that corrects the inputted picture signal by using the luminance value for each of the light sources from the backlight control part, and controls the drive of the display part on the basis of corrected picture signal for each of the pixels, and

the display control part is provided with a color correction computing part that corrects the inputted picture signal by using the CF property.

5. The display device according to claim 4, wherein the display control part corrects the luminance value for each of the light sources from the backlight control part, by using data of a preset PSF (point spread function).

6. The display device according to claim 2, wherein the backlight control part corrects the luminance value of the light source determined at the luminance determining part, by using a preset minimal offset luminance value.

7. The display device according to claim 2, wherein the backlight control part corrects the luminance value for each of the light sources determined at the luminance determining part so that a luminance balance of each illumination area has a value within a predetermined range with respect to an adjacent illumination area.

8. The display device according to claim 2, wherein the backlight control part corrects the luminance value for each of the light sources determined at the luminance determining part so that consistency with a previous display operation at the display part is ensured.

9. The display device according to claim 1, wherein the light sources of at least two colors are light-emitting diodes whose luminescent colors are different from each other.