Liquid crystal display having subpixels per color pixel

• US 8,305,540 B2
• Filed: 04/08/2011
• Issued: 11/06/2012
• Est. Priority Date: 09/24/2004
• Status: Expired due to Fees

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Inventors: Baek, Seung-Soo
• Primary Examiner(s): DUDEK, JAMES A
• Application Number:
  US13/082,974
• Publication Number:
  US 20110187979A1
• Time in Patent Office: 578 Days
• Field of Search: 349/144, 349/147
• US Class Current: 349/144
• CPC Class Codes: G02F 1/133531 characterised by the arrangement of polariser or analyser axes
• 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 1/134336 Matrix
• CPC Class Codes: G02F 1/134345 Subdivided pixels, e.g. for grey scale or redundancy
• CPC Class Codes: G02F 2201/121 common or background

Abstract

A liquid crystal display includes: a first substrate; a gate line disposed on the first substrate; a data line intersecting the gate line; a thin film transistor connected to the gate line and the data line; a coupling electrode connected to the thin film transistor; a first sub-pixel electrode connected to the thin film transistor; a second sub-pixel electrode capacitively coupled to the coupling electrode; a second substrate facing the first substrate; a common electrode disposed on the second substrate; and a polarizer disposed on the first substrate or the second substrate and having a polarization axis. The coupling electrode is elongated substantially parallel to the polarization axis and has a first edge substantially parallel to or substantially perpendicular to the polarization axis.

Claims

1. A liquid crystal display comprising:

a first substrate;

a gate line disposed on the first substrate;

a data line intersecting the gate line;

a thin film transistor comprising a gate electrode connected to the gate line, a source electrode connected to the data line, and a drain electrode;

an interconnection connected to the drain electrode;

a coupling electrode connected to the interconnection;

a passivation layer disposed on the gate line, the data line, the thin film transistor, the interconnection, and the coupling electrode;

a first sub-pixel electrode disposed on the passivation layer and connected to the drain electrode;

a second sub-pixel electrode disposed on the passivation layer, spaced apart from the first sub-pixel electrode, and overlapping the coupling electrode and the interconnection;

a second substrate facing the first substrate; and

a polarizer having polarization axis, disposed on at least one of the first substrate and the second substrate,

wherein the interconnection has a smaller width than that of the coupling electrode, and

wherein the at least one edge of the coupling electrode is substantially parallel to or substantially perpendicular to the polarization axis.

2. The liquid crystal display of claim 1, wherein the interconnection is bent at least once.

3. The liquid crystal display of claim 1, further comprising:

a storage electrode line disposed under the passivation layer.

4. The liquid crystal display of claim 3, wherein the storage electrode line is parallel to the gate line, and

wherein the storage electrode line comprises a first extension portion parallel to the data line.

5. The liquid crystal display of claim 4, wherein the storage electrode further comprises a second extension portion parallel to the gate line.

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

an overpass disposed on the passivation layer, crossing the gate line, and connecting adjacent storage electrode line.

7. The liquid crystal display of claim 6, wherein the first extension portion or the second extension portion is connected to other storage electrode line adjacent to the storage electrode line by the overpass.

8. The liquid crystal display of claim 6, wherein the overpass is made of a same material as the first sub-pixel electrode or the second sub-pixel electrode.

9. The liquid crystal display of claim 8, wherein the overpass is spaced apart from the first sub-pixel electrode and the second sub-pixel electrode.

10. The liquid crystal display of claim 1, wherein the at least one edge of the coupling electrode is parallel to the data line.

11. The liquid crystal display of claim 10, wherein the at least one edge of the coupling electrode comprises a concave portion.

12. The liquid crystal display of claim 1, wherein the coupling electrode approximately has a quadrangular shape.

13. The liquid crystal display of claim 12, wherein the second sub-pixel electrode is approximately trapezoidal and has an edge substantially parallel to the data line.

14. The liquid crystal display of claim 13, wherein the coupling electrode follows a shape of the second sub-pixel electrode such that the coupling electrode is approximately trapezoidal and has an edge substantially parallel to the data line.

15. The liquid crystal display of claim 13, wherein the first-subpixel electrode comprises an upper portion disposed above the second sub-pixel electrode in a longitudinal direction, and a lower portion disposed under the second sub-pixel electrode in the longitudinal direction.

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

a storage electrode disposed under the passivation layer and extending along the data line,

wherein the first-subpixel electrode further comprises a longitudinal connection connecting the upper portion and the lower portion of the first sub-pixel electrode,

the first sub-pixel electrode and the second sub-pixel electrode are spaced apart from each other by a gap, and

the gap comprises a longitudinal portion overlapping the storage electrode.

17. The liquid crystal display of claim 12, wherein a ratio of areas of the first sub-pixel electrode and the second sub-pixel electrode is from about 1:

0.85 to about 1;

1.15.

18. The liquid crystal display of claim 1, wherein the passivation layer comprises an inorganic insulating film and an organic insulating film disposed on the inorganic insulating film.

19. The liquid crystal display of claim 1, wherein the drain electrode, the interconnection, and the coupling electrode are disposed at a same layer.

20. The liquid crystal display of claim 1, further comprising a common electrode facing the first sub-pixel electrode and the second sub-pixel electrode,

wherein at least one of the first sub-pixel electrode, the second sub-pixel electrode, and the common electrode has a cutout for dividing a pixel region into a plurality of domains,

wherein the interconnection extends along an extending direction of the cutout.

21. The liquid crystal display of claim 1, wherein the coupling electrode has a concave portion in the at least one edge of the coupling electrode.