LIQUID CRYSTAL DISPLAY DEVICE

• US 20140168582A1
• Filed: 09/04/2013
• Published: 06/19/2014
• Est. Priority Date: 12/17/2012
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Inventors: CHANG, Hak Sun, RYU, Jang Wi, JANG, Jae-Soo, SHIN, Ki Chul
• Granted Patent: US 9,366,916 B2
• Time in Patent Office: Days
• US Class Current: 349/106
• CPC Class Codes: G02F 1/133707 Structures for producing distorted electric fields, e.g. bumps, protrusions, recesses, slits in pixel electrodes
• CPC Class Codes: G02F 1/133742 for homeotropic alignment
• CPC Class Codes: G02F 1/134309 characterised by their geometrical arrangement
• CPC Class Codes: G02F 1/134318 having a patterned common electrode
• CPC Class Codes: G02F 1/134336 Matrix
• CPC Class Codes: G02F 1/134345 Subdivided pixels, e.g. for grey scale or redundancy
• CPC Class Codes: G02F 1/136222 Colour filters incorporated in the active matrix substrate

Abstract

A liquid crystal display device includes a lower panel having a lower substrate. A pixel electrode is formed on the lower substrate and includes a partial plate electrode and a plurality of minute branch electrodes extending from the partial plate electrode. A lower layer is formed on the lower substrate and below the pixel electrode and includes an inclined portion. An upper panel includes an upper substrate facing the lower substrate and a common electrode formed on the upper substrate. A liquid crystal layer is positioned between the lower panel and the upper panel, in which a part of the inclined portion is overlapped with a part of the minute branch electrode.

Claims

1. A liquid crystal display device, comprising:

a lower panel comprising;

a lower substrate,

a pixel electrode formed on the lower substrate and comprising a partial plate electrode and a plurality of minute branch electrodes extending from the partial plate electrode, and

a lower layer formed on the lower substrate and below the pixel electrode and comprising an inclined portion;

an upper panel comprising an upper substrate facing the lower substrate and a common electrode formed on the upper substrate; and

a liquid crystal layer positioned between the lower panel and the upper panel,

wherein a part of the inclined portion is overlapped with a part of the minute branch electrodes.

2. The liquid crystal display device of claim 1, wherein the lower layer comprising the inclined portion is a color filter or a passivation layer comprising an organic insulator.

3. The liquid crystal display device of claim 2, wherein:

the partial plate electrode has a rhombus shape,

the inclined portion has a rhombus shape, and

the rhombus shape of the inclined portion is larger than the rhombus shape of the partial plate electrode.

4. The liquid crystal display device of claim 3, further comprising:

an extension extending from the partial plate electrode in a vertical or horizontal direction,

wherein the plurality of minute branch electrodes protrudes in the extension.

5. The liquid crystal display device of claim 3, wherein the longest electrode of the minute branch electrodes has a length of between 50 μ

m and 68 μ

m.

6. The liquid crystal display device of claim 3, wherein the length of the longest electrode of the minute branch electrodes has a value of between 25% and 35% of an oblique length of a region occupied by the pixel electrode.

7. The liquid crystal display device of claim 6, wherein an overlapped length of the inclined portion and the minute branch electrode has a value of between 0% and 10% of the oblique length.

8. The liquid crystal display device of claim 3, wherein the common electrode comprises a cutout or a protrusion and has a liquid crystal control means having a cross structure.

9. The liquid crystal display device of claim 8, wherein a cross point of the cross structure of the liquid crystal control means coincides with the center of the partial plate electrode or the inclined portion.

10. The liquid crystal display device of claim 9, wherein the common electrode further comprises an additional liquid crystal control means comprising a cutout or a protrusion.

11. The liquid crystal display device of claim 10, wherein the additional liquid crystal control means is a rhombus cutout pattern or a rhombus protrusion pattern that is positioned at the cross point portion of the cross structure.

12. The liquid crystal display device of claim 11, wherein the liquid crystal control means comprises a disconnected portion in the middle of the cross structure.

13. The liquid crystal display device of claim 10, wherein the additional liquid crystal control means is an X-shaped pattern that is positioned at the cross point portion of the cross structure.

14. The liquid crystal display device of claim 9, wherein the liquid crystal control means comprises a disconnected portion in the middle of the cross structure.

15. The liquid crystal display device of claim 10, wherein ends of the plurality of minute branch electrodes are not connected to each other to protrude outwards.

16. The liquid crystal display device of claim 15, wherein the inclined portion has an inclination throughout the entire region.

17. The liquid crystal display device of claim 15, wherein the inclined portion has an inclination only in a partial region.

18. The liquid crystal display device of claim 15, wherein:

the pixel electrode comprises a first subpixel electrode and a second subpixel electrode, and

the first subpixel electrode and the second subpixel electrode comprise the partial plate electrode and the plurality of minute branch electrodes, respectively.

19. The liquid crystal display device of claim 18, wherein:

the first subpixel electrode is formed in a square region, and

the second subpixel electrode is formed in a rectangular region.

20. The liquid crystal display device of claim 19, wherein the second subpixel electrode comprises two partial plate electrodes.

21. The liquid crystal display device of claim 20, wherein:

the rectangular region is divided into two square regions, and

the two partial plate electrodes are formed in the two square regions, respectively.

22. The liquid crystal display device of claim 19, wherein the second subpixel electrode comprises one partial plate electrode.

23. The liquid crystal display device of claim 15, further comprising:

an alignment layer aligning liquid crystal molecules of the liquid crystal layer,

wherein the liquid crystal layer or the alignment layer comprises a pretilt providing polymer polymerized by light.

24. A liquid crystal display device, comprising:

a lower panel comprising;

a lower substrate,

a pixel electrode formed on the lower substrate and comprising a partial plate electrode and a plurality of minute branch electrodes extending from the partial plate electrode, and

a lower layer formed on the lower substrate and below the pixel electrode and comprising an inclined portion;

an upper panel comprising;

an upper substrate facing the lower substrate, and

a common electrode formed on the upper substrate, wherein the common electrode has a liquid crystal control means comprising a cutout or a protrusion and has a cross structure; and

a liquid crystal layer positioned between the lower panel and the upper panel,

wherein ends of the plurality of minute branch electrodes protrude outwards from the partial plate electrode and are not connected to each other.

25. The liquid crystal display device of claim 24, wherein a part of the inclined portion is overlapped with a part of the minute branch electrode.

26. The liquid crystal display device of claim 25, wherein a cross point of the cross structure of the liquid crystal control means coincides with the center of the partial plate electrode or the inclined portion.

27. The liquid crystal display device of claim 26, wherein the common electrode further comprises an additional liquid crystal control means constituted by a cutout or a protrusion.

28. The liquid crystal display device of claim 27, wherein the additional liquid crystal control means is a rhombus cutout pattern or a rhombus protrusion pattern that is positioned at the cross point portion of the cross structure.

29. The liquid crystal display device of claim 28, wherein the liquid crystal control means comprises a disconnected portion in the middle of the cross structure.

30. The liquid crystal display device of claim 27, wherein the additional liquid crystal control means is an X-shaped pattern that is positioned at the cross point portion of the cross structure.

31. The liquid crystal display device of claim 26, wherein the liquid crystal control means comprises a disconnected portion in the middle of the cross structure.

32. The liquid crystal display device of claim 25, wherein the inclined portion has an inclination throughout the entire region.

33. The liquid crystal display device of claim 25, wherein the inclined portion has an inclination only in a partial region.

34. The liquid crystal display device of claim 25, wherein the lower layer comprising the inclined portion is a color filter or a passivation layer comprising an organic insulator.

35. The liquid crystal display device of claim 34, wherein:

the partial plate electrode has a rhombus shape,

the inclined portion has a rhombus shape, and

the rhombus shape of the inclined portion is larger than the rhombus shape of the partial plate electrode.

36. The liquid crystal display device of claim 35, further comprising:

an extension extending from the partial plate electrode in a vertical or horizontal direction,

wherein the plurality of minute branch electrodes protrudes in the extension.

37. The liquid crystal display device of claim 25, wherein:

the pixel electrode comprises a first subpixel electrode and a second subpixel electrode, and

the first subpixel electrode and the second subpixel electrode comprise the partial plate electrode and the plurality of minute branch electrodes, respectively.

38. The liquid crystal display device of claim 37, wherein:

the first subpixel electrode is formed in a square region, and

the second subpixel electrode is formed in a rectangular region.

39. The liquid crystal display device of claim 38, wherein the second subpixel electrode comprises two partial plate electrodes.

40. The liquid crystal display device of claim 39, wherein:

the rectangular region is divided into two square regions, and

the two partial plate electrodes are formed in the two square regions, respectively.

41. The liquid crystal display device of claim 38, wherein the second subpixel electrode comprises one partial plate electrode.

42. The liquid crystal display device of claim 25, further comprising:

an alignment layer aligning liquid crystal molecules of the liquid crystal layer,

wherein the liquid crystal layer or the alignment layer comprises a pretilt providing polymer polymerized by light such as ultraviolet light.

43. A liquid crystal control apparatus for a liquid crystal display device having a lower panel and an upper panel substantially parallel to each other with a liquid crystal layer positioned between the upper panel and the lower panel, the liquid crystal control apparatus comprising:

a color filter between the liquid crystal layer and the lower panel and having an inclined color filter portion oblique to the upper and lower panels;

a plate electrode layered on the inclined color filter portion; and

a plurality of branch electrodes extending away from an edge of the plate electrode proximal to the upper panel in a direction substantially parallel to the upper and lower panels, ends of the branch electrodes distal from the plate electrode not being connected to each other, and ends of the branch electrodes proximal to the plate electrode overlapping an edge of the inclined color filter portion.

44. The liquid crystal control apparatus of claim 43 comprising a common electrode between a substrate of the upper panel and the liquid crystal layer, the common electrode having cutouts and/or protrusions located above the inclined color filter portion.