Display device, method of driving display device, and electronic apparatus

Patent metadata

Field	Value
Publication number	US-9830886-B2
Application number	US-201514710110-A
Country	US
Kind code	B2
Filing date	May 12, 2015
Priority date	May 15, 2014
Publication date	Nov 28, 2017
Grant date	Nov 28, 2017

Abstract

According to an aspect, a display device includes an image display panel in which pixels each including first to fourth sub-pixels are arranged in a two-dimensional matrix; and a signal processing unit that converts an input signal into an output signal and outputs the generated output signal to the image display panel. The signal processing unit determines an expansion coefficient, obtains a generated signal of the fourth sub-pixel in each pixel based on input signals of the first to the third sub-pixels in the pixel itself and the expansion coefficient, obtains an output signal for the fourth sub-pixel in each pixel based on a generated signal of the fourth sub-pixel in the pixel itself and a generated signal of the fourth sub-pixel in an adjacent pixel to be output to the fourth sub-pixel.

First claim

The invention is claimed as follows:

1. A display device comprising:
an image display panel in which pixels each including a first sub-pixel that displays a first color, a second sub-pixel that displays a second color, a third sub-pixel that displays a third color, and a fourth sub-pixel that displays a fourth color with higher luminance than that of the first sub-pixel, the second sub-pixel, and the third sub-pixel are arranged in a two-dimensional matrix; and
a signal processing unit that converts an input value of an input signal into an extended value in a color space extended with the first color, the second color, the third color, and the fourth color to generate an output signal and outputs the generated output signal to the image display panel, wherein
the signal processing unit
determines an expansion coefficient related to the image display panel,
obtains a generated signal of the fourth sub-pixel in each pixel based on an input signal of the first sub-pixel in the pixel itself, an input signal of the second sub-pixel in the pixel itself, and an input signal of the third sub-pixel in the pixel itself, and the expansion coefficient,
obtains an output signal for the fourth sub-pixel in each pixel based on the generated signal of the fourth sub-pixel in the pixel itself and a generated signal of the fourth sub-pixel in a pixel adjacent thereto to be output to the fourth sub-pixel,
obtains an output signal for the first sub-pixel in each pixel based on at least an input signal of the first sub-pixel, the expansion coefficient, and the output signal for the fourth sub-pixel to be output to the first sub-pixel,
obtains an output signal for the second sub-pixel in each pixel based on at least the input signal of the second sub-pixel, the expansion coefficient, and the output signal for the fourth sub-pixel to be output to the second sub-pixel, and
obtains an output signal for the third sub-pixel in each pixel based on at least the input signal of the third sub-pixel, the expansion coefficient, and the output signal for the fourth sub-pixel to be output to the third sub-pixel, wherein,

each of the pixels is formed such that the first sub-pixel, the second sub-pixel, the third sub-pixel, and the fourth sub-pixel are arranged in a first direction, and the fourth sub-pixel is arranged at an end in the first direction of the pixel,
in the image display panel, the first sub-pixel, the second sub-pixel, the third sub-pixel, and the fourth sub-pixel are linearly arranged in a second direction to form a stripe array, and
the signal processing unit obtains an output signal for the fourth sub-pixel in each pixel based on the generated signal of the fourth sub-pixel in the pixel itself and the generated signal of the fourth sub-pixel in a pixel adjacent thereto in the first direction, and outputs the output signal to the fourth sub-pixel.

2. The display device according to claim 1 , wherein the signal processing unit obtains the output signal for the fourth sub-pixel in each pixel based on the generated signal of the fourth sub-pixel in the pixel itself and the generated signal of the fourth sub-pixel in a pixel adjacent to an end side at which the fourth sub-pixel is arranged, and outputs the output signal to the fourth sub-pixel.

3. The display device according to claim 1 , wherein each of the pixels is formed such that the first sub-pixel, the second sub-pixel, the third sub-pixel, and the fourth sub-pixel are diagonally arranged in a first direction and a second direction.

4. The display device according to claim 1 , wherein the signal processing unit obtains an output signal for the fourth sub-pixel in each pixel based on the generated signal of the fourth sub-pixel in the pixel itself and a generated signal of the fourth sub-pixel in an adjacent pixel having higher luminance than that of the generated signal of the fourth sub-pixel in the pixel itself, and outputs the output signal to the fourth sub-pixel.

5. The display device according to claim 1 , wherein the signal processing unit obtains an output signal for the fourth sub-pixel in each pixel by averaging the generated signal of the fourth sub-pixel in the pixel itself and the generated signal of the fourth sub-pixel in an adjacent pixel with a predetermined ratio, and outputs the output signal to the fourth sub-pixel.

6. The display device according to claim 1 , wherein the fourth color is white.

7. An electronic apparatus comprising:
the display device according to claim 1 ; and
a control device that supplies the input signal to the display device.

8. A method of driving a display device, the display device comprising an image display panel in which pixels each including a first sub-pixel that displays a first color, a second sub-pixel that displays a second color, a third sub-pixel that displays a third color, and a fourth sub-pixel that displays a fourth color with higher luminance than that of the first sub-pixel, the second sub-pixel, and the third sub-pixel are arranged in a two-dimensional matrix, the method comprising:
obtaining an output signal for each of the first sub-pixel, the second sub-pixel, the third sub-pixel, and the fourth sub-pixel; and
controlling an operation of each of the first sub-pixel, the second sub-pixel, the third sub-pixel, and the fourth sub-pixel based on the output signal, wherein
the obtaining of the output signal includes:
determining an expansion coefficient related to the image display panel,
obtaining a generated signal of the fourth sub-pixel in each pixel based on an input signal of the first sub-pixel in the pixel itself, an input signal of the second sub-pixel in the pixel itself, and an input signal of the third sub-pixel in the pixel itself, and the expansion coefficient,
obtaining an output signal for the fourth sub-pixel in each pixel based on the generated signal of the fourth sub-pixel in the pixel itself and a generated signal of the fourth sub-pixel in a pixel adjacent thereto to be output to the fourth sub-pixel,
obtaining an output signal for the first sub-pixel in each pixel based on at least an input signal of the first sub-pixel, the expansion coefficient, and the output signal for the fourth sub-pixel to be output to the first sub-pixel,
obtaining an output signal for the second sub-pixel in each pixel based on at least the input signal of the second sub-pixel, the expansion coefficient, and the output signal for the fourth sub-pixel to be output to the second sub-pixel, and
obtaining an output signal for the third sub-pixel in each pixel based on at least the input signal of the third sub-pixel, the expansion coefficient, and the output signal for the fourth sub-pixel to be output to the third sub-pixel, wherein,

each of the pixels is formed such that the first sub-pixel, the second sub-pixel, the third sub-pixel, and the fourth sub-pixel are arranged in a first direction, and the fourth sub-pixel is arranged at an end in the first direction of the pixel,
in the image display panel, the first sub-pixel, the second sub-pixel, the third sub-pixel, and the fourth sub-pixel are linearly arranged in a second direction to form a stripe array, and
the signal processing unit obtains an output signal for the fourth sub-pixel in each pixel based on the generated signal of the fourth sub-pixel in the pixel itself and the generated signal of the fourth sub-pixel in a pixel adjacent thereto in the first direction, and outputs the output signal to the fourth sub-pixel.

Assignees

• Japan Display Inc

Inventors

• Higashi Amane
• Nagatsuma Toshiyuki
• Sakaigawa Akira
• Kabe Masaaki

Classifications

• G09G2340/06

  Colour space transformation · CPC title

• G09G3/2066

  with error diffusion in both space and time · CPC title

• G09G3/3648

  using an active matrix (G09G3/367 - G09G3/3696 take precedence) · CPC title

• G09G3/2081

  with combination of amplitude modulation and time modulation (space and time error diffusion G09G3/2066) · CPC title

• G09G2330/021

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