IP Library Granted Patent US 7,646,456
Granted Patent B2
US 7,646,456 · App. 11/798,914 · Granted Jan 12, 2010

Liquid crystal display device

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Quick Facts
Patent No.
US 7,646,456
App. No.
11/798,914
Granted
Jan 12, 2010
Kind
B2
Abstract

Disclosed is a liquid crystal display device having an improved display quality. The device includes a substrate; black matrix formed in a matrix pattern on one side of the substrate, wherein the black matrix divides the substrate into a plurality of cell areas; a color filter layer having a red color filter of a first thickness formed in one of the plurality of cell areas, a green color filter of a second thickness which is higher than the first thickness, and a blue color filter of a third thickness which is higher than the second thickness; and a first compensation layer formed by coating the color filter layer and the black matrix with a polymerizable liquid crystal, wherein the first compensation layer is hardened, thereby leveling the substrate, and includes a positive C-plate; and a second compensation layer on another side of the substrate, wherein the second compensation layer is made of one of an A-plate and a biaxial film.

Claims (26)

1. A liquid crystal display device, comprising:

a substrate;

a black matrix formed in a matrix pattern on one side of the substrate, wherein the black matrix divides the substrate into a plurality of cell areas;

a color filter layer having a red color filter of a first thickness formed in one of the plurality of cell areas, a green color filter of a second thickness which is higher than the first thickness, and a blue color filter of a third thickness which is higher than the second thickness; and

a first compensation layer formed by coating the color filter layer and the black matrix with a polymerizable liquid crystal, wherein the first compensation layer is hardened, thereby leveling the substrate, and includes a positive C-plate; and

a second compensation layer on another side of the substrate, wherein the second compensation layer is made of one of an A-plate and a biaxial film.

2. The liquid crystal display device according to claim 1 , wherein a stepped difference between the red color filter and the green color filter is above 0.1 μm and below 0.3 μm, and a stepped difference between the green color filter and the blue color filter is above 0.2 μm and below 0.4 μm.

3. The liquid crystal display device according to claim 1 , wherein the thickness of the first compensation layer corresponding to the red color filter is above about 1.1 times and below about 1.3 times the thickness of the first compensation layer corresponding to the green color filter.

4. The liquid crystal display device according to claim 1 , wherein the thickness of the first compensation layer corresponding to the blue color filter is above 0.7 times and below 0.9 times the thickness of the first compensation layer corresponding to the green color filter.

5. The liquid crystal display device according to claim 1 , wherein the thickness of the first compensation layer corresponding to the red color filter is above 1.60 μm and below 1.70 μm.

6. The liquid crystal display device according to claim 1 , wherein the thickness of the first compensation layer corresponding to the green color filter is above about 1.35 μm and below 1.45 μm.

7. The liquid crystal display device according to claim 1 , wherein the thickness of the first compensation layer corresponding to the blue color filter is above 1.10 μm and below 1.20 μm.

8. The liquid crystal display device according to claim 1 , wherein an upper polarizer is provided on the second compensation layer.

9. A method of fabricating a liquid crystal display device, comprising:

forming a substrate;

forming a black matrix pattern on one side of the substrate, wherein the black matrix is formed to divide the substrate into a plurality of areas, a green color filter of a second thickness which is higher;

forming a color filter layer having a red color filter of a first thickness formed in one of the plurality of cell area, a green color filter of a second thickness which is higher than the first thickness, and a blue color filter of a third thickness which is higher than the second thickness;

forming a first compensation layer formed by coating the color filter layer and the black matrix with a polymerizable liquid crystal, wherein the first compensation layer is hardened, thereby hardening the substrate, and includes a positive C-plate; and

forming a second compensation layer on another side of the substrate, wherein the second compensation layer is made of one of an A-plate and a biaxial film.

10. The method according to claim 9 , wherein a stepped difference formed between the red color filter and the green color filter is above 0.1 μm and below 0.3 μm, and a stepped difference between the green color filter and the blue color filter is above 0.2 μm and below 0.4 μm.

11. The method according to claim 9 , wherein the thickness of the first compensation layer corresponding to the red color filter is above 1.1 times and below 1.3 times the thickness of the first compensation layer corresponding to the green color filter.

12. The method according to claim 9 , wherein the thickness of the first compensation layer corresponding to the blue color filter is above 0.7 times and below 0.9 times the thickness of the first compensation layer corresponding to the green color filter layer.

13. The method according to claim 9 , wherein the thickness of the first compensation layer corresponding to the red color filter is above 1.60 μm and below 1.70 μm.

14. The method according to claim 9 , wherein the thickness of the first compensation layer corresponding to the green color filter is above 1.35 μm and below 1.45 μm.

15. The method according to claim 9 , wherein the thickness of the first compensation layer corresponding to the blue color filter is above 1.10 μm and below 1.20 μm.

16. The method according to claim , 1 wherein an upper polarizer is formed on the second compensation layer.

Assignments (2)
CHANGE OF NAME Recorded Oct 17, 2008
From: LG.PHILIPS LCD CO., LTD.
To: LG DISPLAY CO., LTD.
Reel/Frame 021763/0117 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded May 17, 2007
From: ROH, SU DONG
To: LG.PHILIPS LCD CO., LTD.
Reel/Frame 019367/0087 →