Systems and methods for adjusting liquid crystal display white point using column inversion

Patent metadata

Field	Value
Publication number	US-9368077-B2
Application number	US-201213420197-A
Country	US
Kind code	B2
Filing date	Mar 14, 2012
Priority date	Mar 14, 2012
Publication date	Jun 14, 2016
Grant date	Jun 14, 2016

Abstract

Systems, methods, and devices for adjusting a white point of a liquid crystal display (LCD) using column inversion are provided. In one example, a method includes measuring white points of an electronic display that occur when the display employs different column inversion schemes. The display may be programmed to perform the column inversion scheme that produces a white point closest to a desired white point.

First claim

What is claimed is:

1. A method comprising:
measuring white points of an electronic display that occur when the display employs different column inversion schemes, wherein the white points are the color emitted by the display when the display is programmed to display the color white; and
programming the display to perform one of the different column inversion schemes that produces a white point closest to a desired white point, wherein the desired white point comprises a desired color to be emitted by the display when the display is programmed to display the color white;
wherein the white points of the display are measured when the display employs different 3-column inversion schemes; and
wherein the different 3-column inversion schemes comprise a first 3-column inversion scheme that enhances blue pixel transmittance in relation to red and green pixels, a second 3-column inversion scheme that enhances red pixel transmittance in relation to green and blue pixels, and a third 3-column inversion scheme that enhances green pixel transmittance in relation to red and blue pixels.

2. The method of claim 1 , wherein the white points of the display are measured when the display employs different 2/1-column inversion schemes.

3. The method of claim 2 , wherein the different 2/1-column inversion schemes comprise a first 2/1-column inversion scheme that enhances red and blue pixel transmittance in relation to green pixels, a second 2/1-column inversion scheme that enhances blue and green pixel transmittance in relation to red pixels, and a third 2/1-column inversion scheme that enhances red and green pixel transmittance in relation to blue pixels.

4. The method of claim 1 , wherein the white points of the display are measured when the display employs a 1-column inversion scheme that does not enhance a transmittance of any pixel color in relation to another pixel color.

5. A method of manufacturing an electronic display comprising:
measuring a color of light emitted by a backlight assembly; and
combining the backlight assembly with a display panel configured to perform one of a plurality of column inversion schemes, wherein the one of the plurality of column inversion schemes represents the one of the plurality of column inversion schemes that is expected to cause a white point (the color emitted by the display when the display is programmed to display the color white) of the combination of the backlight assembly and the display panel to most closely approach a desired white point (a color desired to be emitted by the display when the display is programmed to display the color white);
wherein the plurality of column inversion schemes comprises a plurality of 3-column inversion schemes and wherein, when the color of the light emitted by the backlight assembly suggests that a resulting white point using a display panel without column inversion or with 1-column inversion would be deficient in blue, the backlight assembly is combined with the display panel, wherein the display panel is configured to perform a 3-column inversion scheme in which blue pixels are surrounded by pixels driven at the same polarity as the blue pixels.

6. A method of manufacturing an electronic display comprising:
measuring a color of light emitted by a backlight assembly; and
combining the backlight assembly with a display panel configured to perform one of a plurality of column inversion schemes, wherein the one of the plurality of column inversion schemes represents the one of the plurality of column inversion schemes that is expected to cause a white point (the color emitted by the display when the display is programmed to display the color white) of the combination of the backlight assembly and the display panel to most closely approach a desired white point (a color desired to be emitted by the display when the display is programmed to display the color white);
wherein the plurality of column inversion schemes comprises a plurality of 3-column inversion schemes and wherein, when the color of the light emitted by the backlight assembly suggests that a resulting white point using a display panel without column inversion or with 1-column inversion would be deficient in red, the backlight assembly is combined with the display panel, wherein the display panel is configured to perform a 3-column inversion scheme in which red pixels are surrounded by pixels driven at the same polarity as the red pixels.

7. A method of manufacturing an electronic display comprising:
measuring a color of light emitted by a backlight assembly; and
combining the backlight assembly with a display panel configured to perform one of a plurality of column inversion schemes, wherein the one of the plurality of column inversion schemes represents the one of the plurality of column inversion schemes that is expected to cause a white point (the color emitted by the display when the display is programmed to display the color white) of the combination of the backlight assembly and the display panel to most closely approach a desired white point (a color desired to be emitted by the display when the display is programmed to display the color white);
wherein the plurality of column inversion schemes comprises a plurality of 3-column inversion schemes and wherein, when the color of the light emitted by the backlight assembly suggests that a resulting white point using a display panel without column inversion or with 1-column inversion would be deficient in green, the backlight assembly is combined with the display panel, wherein the display panel is configured to perform a 3-column inversion scheme in which green pixels are surrounded by pixels driven at the same polarity as the green pixels.

8. An electronic display comprising:
a display panel comprising columns of pixels; and
driving circuitry configured to drive the pixels according to a duty ratio of a plurality of column inversion schemes;
wherein the driving circuitry is configured to drive the pixels according to a first duty ratio when the electronic display is less than a threshold temperature and according to a second duty ratio when the electronic display is greater than a threshold temperature;
wherein the first duty ratio is configured to shift a white point of the electronic display more toward blue than the second duty ratio.

9. The electronic display of claim 8 , wherein the driving circuitry is configured to drive the pixels in a repeating pattern according to a first column inversion scheme over a first plurality of frames and a second column inversion scheme over a subsequent second plurality of frames.

10. The electronic display of claim 8 , wherein the first duty ratio is configured to shift a white point of the electronic display more toward blue than the second duty ratio.

Assignees

• Ge Zhibing
• Chang Shih Chang
• Chen Cheng
• Bae Hopil
• Xu Ming
• Gettemy Shawn Robert
• Yao Wei H
• Apple Inc

Inventors

• Ge Zhibing
• Chang Shih Chang
• Chen Cheng
• Bae Hopil
• Xu Ming
• Gettemy Shawn Robert
• Yao Wei H

Classifications

• G09G3/3614 Primary

  Control of polarity reversal in general · CPC title

• G09G3/3688

  suitable for active matrices only · CPC title

• G09G2320/0666

  for control of colour parameters, e.g. colour temperature · CPC title

• G09G3/006

  Electronic inspection or testing of displays and display drivers, e.g. of LED or LCD displays (testing individual LED's G01R31/2635; testing lamps G01R31/44; testing of optical features of LCD displays G02F1/1309) · CPC title

• G09G2310/0297

  Special arrangements with multiplexing or demultiplexing of display data in the drivers for data electrodes, in a pre-processing circuitry delivering display data to said drivers or in the matrix panel, e.g. multiplexing plural data signals to one D/A converter or demultiplexing the D/A converter output to multiple columns · CPC title