Display device

Patent metadata

Field	Value
Publication number	US-2016203771-A1
Application number	US-201514858962-A
Country	US
Kind code	A1
Filing date	Sep 18, 2015
Priority date	Jan 14, 2015
Publication date	Jul 14, 2016
Grant date	—

Abstract

A display device including a display panel, a timing controller, a backlight unit, and a backlight controller. The display panel includes a plurality of display blocks, and receives an image signal and display an image. The backlight unit includes a-numbered red light sources, b-numbered green light sources (a and b are natural numbers, b<a), and a-numbered blue light sources, and provides light to the display panel. The backlight controller calculates a red luminance average, a green luminance average, and a blue luminance average of the block image signals, respectively, controls a duty ratio of the red light sources based on the red and green luminance averages, controls a duty ratio of the green light sources based on the green luminance average, and controls a duty ratio of the blue light sources based on the blue and green luminance averages.

First claim

What is claimed is:

1 . A display device comprising:
a display panel including a plurality of display blocks, and configured to receive an image signal and display an image; a timing controller configured to receive the image signal that includes block image signals corresponding to the display blocks, respectively; a backlight unit including a-numbered red light sources, b-numbered green light sources (a and b are natural numbers, b<a), and a-numbered blue light sources, and configured to provide light to the display panel; and a backlight controller configured to calculate a red luminance average, a green luminance average, and a blue luminance average of the block image signals, respectively, control a duty ratio of the red light sources based on the red and green luminance averages, control a duty ratio of the green light sources based on the green luminance average, and control a duty ratio of the blue light sources base on the blue and green luminance averages.

2 . The display device according to claim 1 , wherein the backlight controller includes:
a first duty decider configured to decide a first red duty, a first green duty, a first blue duty respectively from the red, green, and blue luminance averages; and a dimming signal generator configured to generate a red dimming signal, which is configured to be provided to the red light sources, based on the first green duty, generate a green dimming signal, which is configured to be provided to the green light sources, based on the first green duty, and generate a blue dimming signal, which is configured to be provided to the blue light sources, based on the first blue and green duties.

3 . The display device according to claim 2 , wherein the backlight unit includes a plurality of first light source blocks that correspond to the display blocks.

4 . The display device according to claim 3 , wherein a number of the display blocks are m,
wherein a number of the first light source blocks are l, wherein each of the first light source blocks includes n-numbered second light source blocks (m, l, and n are natural numbers, m=l×n).

5 . The display device according to claim 4 , wherein each of the second light source blocks includes a red light source and a blue light source,
wherein one of the n-numbered second light source blocks adjacent each other includes a green light source.

6 . The display device according to claim 4 , wherein the backlight controller further includes:
a maximum green duty decider configured to decide the maximum green duty based on the green luminance average; and a second duty decider configured to decide a second red duty and a second blue duty respectively based on the first red duty and the first blue duty, wherein the dimming signal generator is configured to generate a red dimming signal, which is provided to the red light sources, based the second red duty, generate a green dimming signal, which is provided to the green light sources, based on the maximum green duty, and generate a blue dimming signal, which is provided to the blue light sources, based on the second blue duty.

7 . The display device according to claim 6 , wherein the maximum green duty decider is configured to select the maximum value from green luminance averages of the n-numbered second light source blocks adjacent to each other.

8 . The display device according to claim 7 , wherein the backlight controller further includes:
a first operator generator configured to generate a first operator based on the first green duty and the maximum green duty, wherein the first operator generator is configured to decide the first operator by an equation given in:
the first operator=the first green duty/the maximum green duty.

9 . The display device according to claim 8 , wherein the second duty decider is configured to decide the second red duty by an equation given in:
the second red duty=the first red duty×the first operator,
wherein the second duty decider is configured to decide the second blue duty by an equation given in:
the second blue duty=the first blue duty×the first operator.

10 . The display device according to claim 6 , wherein the dimming signal generator is configured to:
generate the red dimming signal based on the second red duty; generate the green dimming signal based on the maximum green duty; generate the blue dimming signal based on the second blue duty; provide the red and blue dimming signals to the respective second light source blocks; and provide the green dimming signal to the respective first light source blocks.

11 . The display device according to claim 4 , wherein the backlight unit further includes b-numbered cyan light sources,
wherein the backlight controller is configured to further control a duty ratio of the cyan light sources based on the red, green, and blue luminance averages.

12 . The display device according to claim 11 , wherein each of the second light source blocks includes a red light source and a blue light source,
wherein one of the n-numbered second light source blocks adjacent to each other includes a green light source, wherein one of the rest of the second light source blocks includes a cyan light source.

13 . The display device according to claim 11 , wherein the backlight controller further includes:
a maximum green duty decider configured to decide the maximum green duty based on the green luminance average; a second duty decider configured to decide a second red duty and a second blue duty respectively based on the first red and blue duties; and a first cyan duty decider configured to decide a first cyan duty based on the first red and blue duties, wherein the maximum green duty decider is configured to select the maximum value of green luminance averages of the n-numbered second light source blocks adjacent to each other, and decide the maximum green duty based on the maximum green luminance average, wherein the first cyan duty decider is configured to compare the second red duty to the second blue duty, and decide a larger one of the second red and blue duties as the first cyan duty.

14 . The display device according to claim 13 , wherein the backlight controller further includes a first operator generator configured to generate a first operator based on the first green duty and the maximum green duty,
wherein the first operator generator is configured to decide the first operator by an equation given in:
the first operator=the first green duty/the maximum green duty.

15 . The display device according to claim 14 , wherein the second duty decider is configured to decide the second red duty by an equation given in:
the second red duty=the first red duty×the first operator,
wherein the second duty decider is configured to decide the second blue duty by an equation given in:
the second blue duty=the first blue duty×the first operator.

16 . The display device according to claim 15 , wherein the backlight controller further includes a second operator generator configured to count the number of pixels expressing cyan and generate the second operator,
wherein the second operator generator is configured to decide the second operator by an equation given in:
the second operator= X/Y,
where X is the number of pixels, which express cyan, among pixels belonging respectively to the second light source blocks and Y is the number of pixels belonging respectively to the second light source blocks.

17 . The display device according to claim 16 , wherein the backlight controller furt

Assignees

• Samsung Display Co Ltd

Inventors

• Kwon Yong-Hoon
• Kim Junghyun
• Nam Seokhyun
• Song Hee-Kwang
• Shin Ho-Sik

Classifications

• G09G3/3413 Primary

  Details of control of colour illumination sources · CPC title

• G09G2360/16

  Calculation or use of calculated indices related to luminance levels in display data · CPC title

• G09G2330/021

  Power management, e.g. power saving · CPC title

• G09G2320/0646

  Modulation of illumination source brightness and image signal correlated to each other · CPC title

• G09G3/3426

  the different display panel areas being distributed in two dimensions, e.g. matrix · CPC title