Transflective liquid crystal display

• US 9,709,848 B2
• Filed: 01/11/2017
• Issued: 07/18/2017
• Est. Priority Date: 04/17/2015
• Status: Active Grant

• Current Assignee: Amel Technology, LLC
• Original Assignee: Amel Technology, LLC
• Inventors: Neveux, Nathanael
• Primary Examiner(s): CHIEN, LUCY P
• Application Number:
  US15/403,938
• Publication Number:
  US 20170123270A1
• Time in Patent Office: 188 Days
• Field of Search: 349 61, 349114, 349106
• CPC Class Codes: G02F 1/133514 Colour filters
• CPC Class Codes: G02F 1/133521 Interference filters
• CPC Class Codes: G02F 1/133555 Transflectors
• CPC Class Codes: G02F 1/133602 Direct backlight
• CPC Class Codes: G02F 1/133626 providing two modes of illumination, e.g. day-night
• CPC Class Codes: G02F 2201/52 RGB geometrical arrangements
• CPC Class Codes: G02F 2203/01 transmissive
• CPC Class Codes: G09G 2360/144 the light being ambient light
• CPC Class Codes: G09G 3/3607 for displaying colours or for displaying grey scales with a specific pixel layout, e.g. using sub-pixels display of colours in flat matrix panels other than liquid crystal displays G09G3/2003; grey scales specific for television H04N3/127

Abstract

A pixel of a transflective liquid crystal display panel having a controllable backlight comprises an array of sub-pixels and a color substrate with an array of colors corresponding to the array of sub-pixels, the array of colors comprising transmissive colors and reflective colors. The color substrate transmits at least one wavelength of light corresponding to the transmissive colors in the array of colors when the controllable backlight emits a first predetermined light level and, from substantially the same area in the color substrate, reflects at least one wavelength of light corresponding to the reflective colors in the array of colors when the controllable backlight emits a second predetermined light level. The transmissive colors may be primary or secondary colors, and the reflective colors may be primary or secondary colors. The primary colors may form the top row of the array of sub-pixels and the secondary colors may form the bottom row of the array of sub-pixels, or at least one of the primary colors and at least one of the secondary colors may form the top row of the array of sub-pixels, and at least one of the primary colors and at least one of the secondary colors may form the bottom row of the array of sub-pixels.

Claims

1. A pixel of a transflective liquid crystal display panel, the display panel having a controllable backlight, comprising:

an array of sub-pixels;

a color substrate with an array of colors corresponding to the array of sub-pixels, the array of colors comprising transmissive colors and reflective colors, the reflective colors being the complement of the transmissive colors, the color substrate transmitting at least one wavelength of light corresponding to the transmissive colors in the array of colors when the controllable backlight emits a first predetermined light level and, from substantially the same area in the color substrate, reflecting at least one wavelength of light corresponding to the reflective colors in the array of colors when the controllable backlight emits a second predetermined light level; and

wherein the transmissive colors are primary or secondary colors and the reflective colors are primary or secondary colors.

2. The pixel according to claim 1, wherein the primary colors form the top row of the array of sub-pixels, and the secondary colors form the bottom row of the array of sub-pixels.

3. The pixel according to claim 1, wherein at least one of the primary colors and at least one of the secondary colors form the top row of the array of sub-pixels, and at least one of the primary colors and at least one of the secondary colors form the bottom row of the array of sub-pixels.

4. The pixel according to claim 2, wherein the order of the primary colors in the top row of the array of sub-pixels is red, green and blue, and the order of the secondary colors in the bottom row of the array of sub-pixels is cyan, magenta and yellow.

5. The pixel according to claim 3, wherein the order of the primary and secondary colors in the top row of the array of sub-pixels is either red, magenta and blue or cyan, green and yellow;

and the order of the primary and secondary colors in the bottom row of the array of sub-pixels is either cyan, green and yellow or red, magenta and blue.

6. The pixel according to claim 1, wherein the display panel further comprises a light sensor, the light sensor measuring the level of ambient light entering the display panel.

7. The pixel according to claim 6, wherein the first predetermined light level is greater than the measured ambient light level and the second predetermined light level is less than the measured ambient light level.

8. The pixel according to claim 1, wherein the first predetermined light level is substantially equal to the second predetermined light level.

9. The pixel according to claim 6, wherein the first predetermined light level, the second predetermined light level, or both predetermined light levels are between 55 percent and 105 percent of the measured ambient light level.

10. A liquid crystal display panel comprising a plurality of pixels wherein at least one of the pixels is the pixel of claim 1.

11. A transflective liquid crystal display comprising:

a panel divided into an array of pixels, each pixel divided into an array of sub-pixels, the panel having a top substrate;

a liquid crystal layer located behind the top substrate;

a color substrate located behind the liquid crystal layer, the color substrate comprising an array of colors corresponding to the array of sub-pixels, the array of colors comprising transmissive colors and reflective colors, the reflective colors being the complement of the transmissive colors, wherein the transmissive colors are primary or secondary colors, and the reflective colors are primary or secondary colors;

a controllable backlight system located behind the color substrate; and

the color substrate transmitting at least one wavelength of light corresponding to the transmissive colors in the array of colors when the controllable backlight emits a first predetermined light level and, from substantially the same area in the color substrate, reflecting at least one wavelength of light corresponding to the reflective colors in the array of colors when the controllable backlight emits a second predetermined light level.

12. The panel according to claim 11, wherein the primary colors form the top row of the array of sub-pixels, and the secondary colors form the bottom row of the array of sub-pixels.

13. The panel according to claim 11, wherein at least one of the primary colors and at least one of the secondary colors form the top row of the array of sub-pixels, and at least one of the primary colors and at least one of the secondary colors form the bottom row of the array of sub-pixels.

14. The panel according to claim 12, wherein the order of the primary colors in the top row of the array of sub-pixels is red, green and blue, and the order of the secondary colors in the bottom row of the array of sub-pixels is cyan, magenta and yellow.

15. The panel according to claim 13, wherein the order of the primary and secondary colors in the top row of the array of sub-pixels is either red, magenta and blue or cyan, green and yellow;

and the order of the primary and secondary colors in the bottom row of the array of sub-pixels is either cyan, green and yellow or red, magenta and blue.

16. A pixel of a transflective liquid crystal display panel, the display panel having a controllable backlight, comprising:

an array of sub-pixels;

a color substrate with an array of colors corresponding to the array of sub-pixels, the array of colors comprising transmissive colors and reflective colors, the reflective colors being the complement of the transmissive colors, the color substrate transmitting at least one wavelength of light corresponding to the transmissive colors in the array of colors when the controllable backlight emits a first predetermined light level and, from substantially the same area in the color substrate, reflecting at least one wavelength of light corresponding to the reflective colors in the array of colors when the controllable backlight emits a second predetermined light level.

17. The pixel according to claim 16, wherein the display panel further comprises a light sensor, the light sensor measuring the level of ambient light entering the display panel.

18. The pixel according to claim 17, wherein the transmissive colors are primary colors and the reflective colors are secondary colors when the first predetermined light level is greater than the measured ambient light level.

19. The panel according to claim 17, wherein the transmissive colors are secondary colors and the reflective colors are primary colors when the second predetermined light level is less than the measured ambient light level.

20. A liquid crystal display panel comprising a plurality of pixels wherein at least one of the pixels is the pixel of claim 16.