DISPLAY DEVICE

• US 20100309107A1
• Filed: 10/08/2008
• Published: 12/09/2010
• Est. Priority Date: 02/14/2008
• Status: Abandoned Application

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Hashimoto, Katsuteru, Otoi, Katsuya, Fujiwara, Kohji, Muroi, Takao
• Application Number:
  US12/867,691
• Publication Number:
  US 20100309107A1
• Time in Patent Office: Days
• US Class Current: 345/88
• CPC Class Codes: G02F 1/133601 for spatial active dimming
• CPC Class Codes: G02F 1/133603 with LEDs
• CPC Class Codes: G02F 1/133609 including means for improving the color mixing, e.g. white
• CPC Class Codes: G02F 1/133624 characterised by their spectral emissions
• CPC Class Codes: G09G 2320/0233 Improving the luminance or brightness uniformity across the screen
• CPC Class Codes: G09G 2320/0242 Compensation of deficiencies in the appearance of colours
• CPC Class Codes: G09G 2320/064 by time modulation of the brightness of the illumination source
• 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 liquid crystal display device with high color reproduction ability even when an area active backlight is driven. A liquid crystal display device (1) of the present invention drives a liquid crystal panel (2) and a backlight device (3), respectively, using a video signal input from outside. In the backlight device (3), a plurality of illuminating areas (Ha) are set on LED substrates (7) with respect to a plurality of display areas provided on the liquid crystal panel (2), and area active backlight drive is performed, which lights up light-emitting diodes (8) in the unit of the illuminating areas. When a backlight data processing part (lighting control part) (15) determines that a brightness signal value indicated for a blue light-emitting diode (light source of a predetermined color) (8b) is larger than brightness signal values indicated for other light-emitting diodes (8r, 8g), and determines that a value obtained by multiplying the brightness signal value indicated for the blue light-emitting diode (8b) by a predetermined ratio is equal to or more than the bright signal values indicated for the other light-emitting diodes (8r, 8g), the backlight data processing part (15) lights up the other light-emitting diodes (8r, 8g), using the brightness signal value indicated for the blue light-emitting diode (8b).

Claims

1. A display device including a backlight part having a light-emitting part that emits illumination light and a display part configured so as to be capable of displaying information in color, using the illumination light from the backlight part,

the display part having a plurality of pixels, and each of the pixels being provided with color filters formed of a plurality of colors,

the display device comprising:

a plurality of illuminating areas provided in the light-emitting part;

a plurality of light sources that are provided for each of the illuminating areas and emit light of colors corresponding to the colors of the color filters; and

a lighting control part that controls each lighting drive of the plurality of light sources in each of the plurality of illuminating areas, using an indication signal input from outside,

wherein the color filter formed of a predetermined color among the color filters formed of a plurality of colors provided on each of the pixels has characteristics of transmitting light from the light source of the predetermined color corresponding to the color filter and light form the other light sources, and

when the lighting control part determines that a brightness signal value indicated for the light source of the predetermined color is larger than brightness signal values indicated for the other light sources in each of the plurality of illuminating areas and that a value obtained by multiplying the brightness signal value indicated for the light source of the predetermined color by a predetermined ratio is equal to or more than the brightness signal values indicated for the other light sources, the lighting control part lights up the other light sources, using the brightness signal value indicated for the light source of the predetermined color.

2. The display device according to claim 1, wherein a plurality of display areas, upon which light from the plurality of illuminating areas is incident respectively, are set in the display part,

the display device including a display control part that drives the display part in a unit of the pixels, using an input video signal,

wherein the lighting control part determines a brightness value of light emitted from the corresponding light source for each of the illuminating areas, using the input video signal, and

the display control part corrects the input video signal, using the brightness value for each of the illuminating areas from the lighting control part, and drives the display part based on the corrected video signal in the unit of the pixels.

3. The display device according to claim 2, wherein the display control part corrects the brightness value for each of the illuminating areas from the lighting control part, using data on a previously set point spread function (PSF).

4. The display device according to claim 1,

wherein light-emitting diodes are used as the light sources.

5. The display device according to claim 1,

wherein red, green, and blue light-emitting diodes that emit red light, green light, and blue light, respectively, are used as the light sources, and

when the lighting control part determines that a brightness signal value indicated for the blue light-emitting diode is larger than a brightness signal value indicated for the green light-emitting diode in each of the plurality of illuminating areas and that a value obtained by multiplying the brightness signal value indicated for the blue light source by the predetermined ratio is equal to or more than the brightness signal value indicated for the green light-emitting diode, the lighting control part lights up the green light-emitting diode, using the brightness signal value indicated for the blue light-emitting diode.

6. The display device according to claim 1, wherein the lighting control part uses the predetermined ratio previously determined based on predetermined CF characteristics of the color filters and predetermined emission characteristics of the light sources.

7. The display device according to claim 1, comprising a storage part that stores a plurality of kinds of the predetermined ratios, and a selecting and indicating part that selects one kind of predetermined ratio from the plurality of kinds of predetermined ratios stored in the storage part based on an indication signal from outside and outputs the selected predetermined ratio to the lighting control part.

8. The display device according to claim 7, wherein the indication signal is a display mode indication signal indicating a display mode in the display part.