Display device, module, and electronic device

Patent metadata

Field	Value
Publication number	US-10558092-B2
Application number	US-201715455244-A
Country	US
Kind code	B2
Filing date	Mar 10, 2017
Priority date	Mar 15, 2016
Publication date	Feb 11, 2020
Grant date	Feb 11, 2020

Abstract

A high-definition liquid crystal display device is provided. A liquid crystal display device with a high aperture ratio is provided. A liquid crystal display device with a high contrast ratio and display quality is provided. A liquid crystal display device capable of being driven at a low voltage is provided. The display device includes, between a pair of substrates, a pixel electrode, a first common electrode, a second common electrode, and a liquid crystal layer. The pixel electrode and the first common electrode are positioned between the liquid crystal layer and one of the substrates. The second common electrode is positioned between the liquid crystal layer and the other substrate. The same potential is supplied to the first common electrode and the second common electrode. The first common electrode includes a portion overlapping with the second common electrode between the display regions of two adjacent subpixels that exhibit different colors. At least one of the pixel electrode and the first common electrode includes a portion that does not overlap with the second common electrode in the display region of the subpixel.

First claim

The invention claimed is:

1. A display device comprising a pixel,
wherein the pixel comprises a plurality of subpixels,
wherein each of the subpixels comprises a display region,
wherein the display device comprises, between a pair of substrates, a pixel electrode, a first common electrode, a second common electrode, and a liquid crystal layer,
wherein the pixel electrode and the first common electrode are positioned between the liquid crystal layer and one of the substrates,
wherein the second common electrode is positioned between the liquid crystal layer and the other substrate,
wherein the same potential is supplied to the first common electrode and the second common electrode,
wherein the first common electrode includes a portion overlapping with the second common electrode between the display regions of two adjacent subpixels that exhibit different colors,
wherein at least one of the pixel electrode and the first common electrode includes a portion that does not overlap with the second common electrode in the display region of the subpixel,
wherein the second common electrode includes an opening in the display region of the subpixel,
wherein, when a thickness of the liquid crystal layer is denoted by d, a width of the opening is greater than or equal to d/6 and narrower than a width of the subpixel,
wherein, when a thickness of the liquid crystal layer is denoted by d, a distance between the openings of two adjacent subpixels is greater than or equal to d and less than or equal to 2.5d, and
wherein a thickness of the liquid crystal layer is greater than or equal to 1 μm and less than or equal to 3 μm.

2. The display device according to claim 1 ,
wherein the first common electrode is electrically connected to the second common electrode.

3. The display device according to claim 1 ,
wherein a liquid crystal included in the liquid crystal layer has a negative dielectric anisotropy.

4. The display device according to claim 1 , further comprising a transistor,
wherein the transistor includes a semiconductor layer,
wherein the semiconductor layer includes an oxide semiconductor in a channel formation region, and
wherein the pixel electrode is electrically connected to the transistor.

5. The display device according to claim 4 ,
wherein the semiconductor layer includes indium, zinc, and one of aluminum, gallium, yttrium, and tin.

6. The display device according to claim 1 , further comprising a scan line and a signal line,
wherein a direction in which the scan line extends intersects with a direction in which the signal line extends, and
wherein the plurality of subpixels exhibiting the same color are aligned in a direction intersecting with the direction in which the signal line extends.

7. A module comprising:
the display device according to claim 1 ; and
a flexible printed circuit board or an integrated circuit.

8. An electronic device comprising:
the module according to claim 7 ; and
an antenna, a battery, a housing, a camera, a speaker, a microphone, or a control button.

9. A display device comprising a pixel,
wherein the pixel comprises a plurality of subpixels,
wherein each of the subpixels comprises a display region,
wherein the display device comprises a pixel electrode, a first common electrode, a second common electrode, and a liquid crystal layer,
wherein each of the pixel electrode and the first common electrode faces the second common electrode with the liquid crystal layer therebetween in a thickness direction of the display device,
wherein the same potential is supplied to the first common electrode and the second common electrode,
wherein the first common electrode includes a portion overlapping with the second common electrode between the display regions of two adjacent subpixels that exhibit different colors,
wherein at least one of the pixel electrode and the first common electrode includes a portion that does not overlap with the second common electrode in the display region of the subpixel,
wherein the second common electrode includes an opening in the display region of the subpixel,
wherein, when a thickness of the liquid crystal layer is denoted by d, a width of the opening is greater than or equal to d/6 and narrower than a width of the subpixel,
wherein, when a thickness of the liquid crystal layer is denoted by d, a distance between the openings of two adjacent subpixels is greater than or equal to d and less than or equal to 2.5d, and
wherein a thickness of the liquid crystal layer is greater than or equal to 1 μm and less than or equal to 3 μm.

10. The display device according to claim 9 ,
wherein the first common electrode is electrically connected to the second common electrode.

11. The display device according to claim 9 ,
wherein a liquid crystal included in the liquid crystal layer has a negative dielectric anisotropy.

12. The display device according to claim 9 , further comprising a transistor,
wherein the transistor includes a semiconductor layer,
wherein the semiconductor layer includes an oxide semiconductor in a channel formation region, and
wherein the pixel electrode is electrically connected to the transistor.

13. The display device according to claim 12 ,
wherein the semiconductor layer includes indium, zinc, and one of aluminum, gallium, yttrium, and tin.

14. The display device according to claim 9 , further comprising a scan line and a signal line,
wherein a direction in which the scan line extends intersects with a direction in which the signal line extends, and
wherein the plurality of subpixels exhibiting the same color are aligned in a direction intersecting with the direction in which the signal line extends.

15. A module comprising:
the display device according to claim 9 ; and
a flexible printed circuit board or an integrated circuit.

16. An electronic device comprising:
the module according to claim 15 ; and
an antenna, a battery, a housing, a camera, a speaker, a microphone, or a control button.

Assignees

• Semiconductor Energy Lab

Inventors

• Yoshitomi Shuhei
• Kubota Daisuke
• Kusunoki Koji

Classifications

• G06F1/3265

  Power saving in display device · CPC title

• G02F2201/123

  pixel · CPC title

• G02F1/134309 Primary

  characterised by their geometrical arrangement · CPC title

• G02F1/136286

  Wiring, e.g. gate line, drain line · CPC title

• G06F3/044

  by capacitive means · CPC title