Patterned vertically aligned liquid crystal display

• US 6,577,366 B1
• Filed: 10/13/1999
• Issued: 06/10/2003
• Est. Priority Date: 10/13/1998
• Status: Expired due to Term

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Park, Seung-Beom, Song, Jang-Kun, Kim, Kyeong-Hyeon, Lee, Kye-Hun
• Primary Examiner(s): DUDEK, JAMES A
• Application Number:
  US09/417,076
• Time in Patent Office: 1,336 Days
• Field of Search: 349/39, 349/143, 349/139, 349/146
• US Class Current: 349/139
• CPC Class Codes: G02F 1/133512 Light shielding layers, e.g. black matrix G02F1/136209 takes precedence
• 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 1/134309 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 1/136213 Storage capacitors associated with the pixel electrode
• CPC Class Codes: G02F 1/136259 Repairing; Defects
• CPC Class Codes: G02F 1/136263 Line defects
• CPC Class Codes: G02F 1/136272 Auxiliary lines
• CPC Class Codes: G02F 1/1393 the birefringence of the liquid crystal being electrically controlled, e.g. ECB-, DAP-, HAN-, PI-LC cells G02F1/1396, G02F1/141 take precedence
• CPC Class Codes: G02F 2201/122 having a particular pattern
• CPC Class Codes: G02F 2201/128 field shaping
• CPC Class Codes: G02F 2201/40 Arrangements for improving the aperture ratio

Abstract

In a vertically aligned mode LCD, a gate line and a storage line are formed on a substrate in parallel, and a storage electrode and a cover pattern are formed as branches of the storage line. The storage electrode is overlapped with an aperture of a common electrode formed on an upper substrate. The cover pattern is located between a pixel electrode and a data line to prevent a light leakage. Accordingly, an alignment error margin of the upper substrate and the lower substrate is increased, an aperture ratio is enhanced, and repairing the high pixel defect is possible. Further, the light leakage caused by a voltage of the data line is prevented.

Claims

1. A liquid crystal display, wherein a long axis of a liquid crystal molecule is arranged in perpendicular to a substrate when electric field is not applied, comprising:

a gate line formed on a lower substrate;

a first storage line formed on the lower substrate;

a data line formed on the lower substrate crossing and insulated from the gate line and the first storage line;

a pixel electrode formed on the lower substrate crossing and insulated from the first storage line, wherein an outer boundary of the pixel electrode is rugged; and

a common electrode formed on an upper substrate and having an aperture pattern dividing the pixel electrode into a plurality of sections.

2. The liquid crystal display of claim 1, wherein an outer boundary of the aperture pattern as well as the outer boundary of the pixel electrode are curved or bent in an obtuse angle.

3. The liquid crystal display of claim 2, wherein the sections of the pixel electrode divided by the aperture pattern make a closed loop.

4. The liquid crystal display of claim 1, wherein the rugged outer boundary of the pixel electrode is horizontally symmetric, and the aperture pattern of the common electrode divides the pixel electrode symmetrically.

5. The liquid crystal display of claim 4, further comprising a storage electrode that is connected to the first storage line and overlaps the aperture pattern.

6. The liquid crystal display of claim 5, wherein the aperture pattern includes a plurality of shapes extending in a direction opposite to a longitudinal axis of the aperture pattern, the shapes progressively narrowing to a point at an end thereof and being spaced at uniform intervals along a length of the aperture pattern.

7. The liquid crystal display of claim 6, wherein the storage electrode has projections which extend in a direction opposite to a longitudinal axis of the storage electrode, a center of the projections corresponding to a center of the shapes of the aperture pattern.

8. The liquid crystal display of claim 5, further comprising a second storage line that is connected to and crosses the storage electrode, and is formed on a same layer as, and in parallel with, the first storage line.

9. The liquid crystal display of claim 8, further comprising a redundant gate line located on the first gate line and between two adjacent data lines.

10. A liquid crystal display, wherein a long axis of a liquid crystal molecule is arranged in perpendicular to a substrate when electric field is not applied, comprising:

a gate line formed on a lower substrate;

a storage line formed on the lower substrate;

a data line formed on the lowe substrate crossing and insulated from the gate line and the storage line;

a common electrode formed on an upper substrate and having an aperture pattern dividing the pixel electrode into a plurality of sections; and

a first cover pattern and a second cover pattern which are branched from the storage line.

11. The liquid crystal display of claim 10, wherein the first cover pattern and the second cover pattern partially overlap the pixel electrode-and the data lines.

12. The liquid crystal display of claim 10, wherein the first cover pattern and the second cover pattern partially overlap the data line only.

13. The liquid crystal display of claim 10, wherein an outer boundary of the cover patterns follow along an outer boundary of the pixel electrode and the data line to maintain a uniform gap between the cover patterns and the pixel electrode and the data line.

14. The liquid crystal display of claim 10, further comprising a redundant gate line located on the first gate line and between two adjacent data lines.

15. A liquid crystal display, wherein a long axis of a liqujid crystal molecule is arranged in perpendicular to a substrate when electric field is not applied, comprising:

a first gate line formed on a lower substrate;

a second gate line that is parallel to the first gate line;

a connector connecting the first gate line and the second gate line;

a storage line formed on the lower substrate;

a data line formed on the lower substrate crossing and insulated from the first gate line and the first storage line;

a pixel electrode formed on the lower substrate crossing and insulated from the first storage line; and

a common electrode formed on an upper substrate and having an aperture pattern dividing the pixel electrode into a plurality of sections.

16. The liquid crystal display of claim 15, wherein the pixel electrode is made of indium tin oxide.

17. The liquid crystal display of claim 15, wherein a voltage of the common electrode is applied to the storage line.

18. The liquid crystal display of claim 15, wherein the storage line overlaps the aperture pattern.

19. The liquid crystal display of claim 18, wherein said storage electrode overlaps the aperture pattern.

20. A liquid crystal display, wherein a long axis of a liquid crystal molecule is arranged in perpendicular to a substrate when electric field is not applied, comprising:

a gate line formed on a lower substrate;

a storage line formed on the lower substrate;

a data line formed on the lower substrate crossing and insulated from the gate line and the storage line;

a pixel electrode formed on the lower substrate crossing and insulated from the storage line, the pixel electrode having a first aperture pattern;

a common electrode formed on an upper substrate; and

a storage electrode branched from said storage line and formed corresponding to the first aperture pattern,

wherein the common electrode has a second aperture pattern arranged alternately with the first aperture pattern, an edge. of the second aperture pattern being adjacent to an edge of the first aperture pattern, and

wherein the second aperture pattern has a square ring type shape, and the first aperture pattern is located between two opposing sides of the second aperture pattern and has a shape forming several crosses having widths that are progressively narrowed in a direction away from a center of each cross, the crosses being aligned in a line.

21. The liquid crystal display of claim 20, wherein said storage electrode overlaps the first aperture pattern.

22. The liquid crystal display of claim 21, wherein the storage electrode has a projection that is concentric with the aperture pattern.

23. The liquid crystal display of claim 20, further comprising a second storage line located on a same layer as the first storage line, the second storage line being parallel with the first storage line, and connected to and crossed by a storage electrode.

24. The liquid crystal display of claim 20, further comprising a redundant gate line located on the gate line and between two adjacent data lines.

25. The liquid crystal display of claim 20, wherein a part of the storage line overlaps the first aperture pattern and the second aperture pattern.

26. The liquid crystal display of claim 20, wherein said storage electrode overlaps the first aperture pattern and the second aperture pattern.

27. The liquid crystal display of claim 20, wherein the first aperture pattern includes a first bottom aperture and a second bottom aperture obliquely extending from a first boundary of the pixel electrode to a second boundary and which are symmetrical to each other, and a third bottom aperture extending from the second boundary to the first boundary,

the common electrode has a second aperture pattern including a first top aperture and a second top aperture extending obliquely and symmetrical to each other, and a third top aperture angled at a mid point and being equidistant from the first top aperture and the second top aperture,

the first aperture pattern and the second aperture pattern are arranged alternately, and

the first storage line overlaps at least a portion of the second aperture pattern.

28. The liquid crystal display of claim 27, further including a branch electrode connected to the storage line and overlapping the second aperture pattern.

29. The liquid crystal display of claim 27, wherein the second aperture pattern includes branch apertures overlapping boundaries of the pixel electrode.