FRINGE FIELD SWITCH LIQUID CRYSTAL DISPLAY AND COLOR FILTER SUBSTRATE

• US 20150022767A1
• Filed: 03/26/2014
• Published: 01/22/2015
• Est. Priority Date: 07/19/2013
• Status: Active Grant

• Current Assignee: Shanghai Tianma Micro-Electronics Company Limited (Tianma Microelectronics Company Limited), Tianma Microelectronics Company Limited
• Original Assignee: Shanghai Tianma Micro-Electronics Company Limited (Tianma Microelectronics Company Limited), Tianma Microelectronics Company Limited
• Inventors: Wang, Yongzhi, HAN, Lijing, Luo, Liyuan
• Granted Patent: US 9,366,921 B2
• Time in Patent Office: Days
• US Class Current: 349/106
• CPC Class Codes: G02F 1/133512 Light shielding layers, e.g. black matrix G02F1/136209 takes precedence
• CPC Class Codes: G02F 1/133514 Colour filters
• CPC Class Codes: G02F 1/134363 for applying an electric field parallel to the substrate, i.e. in-plane switching [IPS]
• CPC Class Codes: G02F 1/134372 for fringe field switching [FFS] where the common electrode is not patterned
• CPC Class Codes: G02F 1/134381 Hybrid switching mode, i.e. for applying an electric field with components parallel and orthogonal to the substrates
• CPC Class Codes: G02F 2201/128 field shaping

Abstract

The present invention discloses a fringe field switching (FFS) liquid crystal display and a color filter substrate. The liquid crystal display includes an upper substrate, a lower substrate, and a liquid crystal layer sandwiched between the upper substrate and the lower substrate. The lower substrate includes a common electrode and a pixel electrode, and the pixel electrode includes at least one branch electrode and an end electrode for connecting the branch electrode; and an auxiliary electrode corresponding to the end electrode is arranged on the upper substrate. In the presence of the auxiliary electrode, unwanted electric fields between the end electrode and the common electrode are effectively attenuated, and arrangement of liquid crystal molecules at the boundary of a pixel element where the end electrode is located is stabilized, so that disclination lines are improved, pictures are displayed uniformly with high quality.

Claims

1. A fringe field switching liquid crystal display, comprising:

an upper substrate;

a lower substrate; and

a liquid crystal layer sandwiched between the upper substrate and the lower substrate,

wherein the lower substrate comprises a common electrode and a pixel electrode,

wherein the pixel electrode comprises at least one branch electrode and an end electrode for connecting the at least one branch electrode, and

wherein an auxiliary electrode corresponding to the end electrode is arranged on the upper substrate.

2. The fringe field switching liquid crystal display of claim 1, wherein the end electrode has a straight-bar shape, a folded-line shape, or a curved shape.

3. The fringe field switching liquid crystal display of claim 1, wherein the auxiliary electrode is arranged in parallel to the end electrode at a preset distance from the end electrode, the preset distance being a distance between a lower fringe of the auxiliary electrode close to the end electrode and an upper fringe of the end electrode close to the auxiliary electrode.

4. The fringe field switching liquid crystal display of claim 3, wherein the preset distance is between 0 and 1 micron.

5. The fringe field switching liquid crystal display of claim 1, wherein the auxiliary electrode and the common electrode have a same potential.

6. The fringe field switching liquid crystal display of claim 1, wherein the pixel electrode is arranged on an upper layer of the common electrode and is insulated from the common electrode.

7. The fringe field switching liquid crystal display of claim 1, wherein the upper substrate comprises a black matrix, and the auxiliary electrode is arranged on an upper layer of the black matrix.

8. The fringe field switching liquid crystal display of claim 7, wherein the upper substrate further comprises a color filter layer, and the auxiliary electrode is arranged between the black matrix and the color filter layer.

9. The fringe field switching liquid crystal display of claim 1, wherein the auxiliary electrode is made of a transparent material or a nontransparent material.

10. The fringe field switching liquid crystal display of claim 1, wherein the auxiliary electrode and the end electrode have the same shape.

11. The fringe field switching liquid crystal display of claim 1, wherein the pixel electrode comprises at least two branch electrodes extending parallel to each other.

12. The fringe field switching liquid crystal display of claim 1, wherein the branch electrode has a straight-bar shape or a non-straight-bar shape.

13. The fringe field switching liquid crystal display of claim 12, wherein the non-straight bar shape is of a zigzag shape, a Z shape, or a folded-line shape.

14. A color filter substrate of a fringe field switching liquid crystal display comprising:

a substrate comprising;

a plurality of pixel elements, each pixel element comprising a display area and a non-display area;

a black matrix formed in the non-display area of the pixel elements; and

a plurality of auxiliary electrodes formed on the black matrix and arranged on one side of the pixel elements.

15. The color filter substrate of claim 14, wherein the substrate further comprises a color filter layer, and the auxiliary electrodes are arranged between the color filter layer and the black matrixes.

16. The color filter substrate of claim 14, wherein the auxiliary electrodes are made of a transparent material or a nontransparent material.

17. The color filter substrate of claim 14, wherein the auxiliary electrodes each have a straight-bar shape, a folded-line shape, or a curved shape.

18. The color filter substrate of claim 14, wherein the auxiliary electrodes are electrically connected with each other.