LIGHT GUIDE PLATE AND LIQUID CRYSTAL DISPLAY HAVING THE SAME

• US 20080246904A1
• Filed: 06/24/2008
• Published: 10/09/2008
• Est. Priority Date: 08/20/2002
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Bang-Sil Choi, Jae Ik Lim, Jong-Whan Cho, Kee-Han Uh, Sang-Jin Pak, Sang-Woo Park
• Inventors: Pak, Sang-Jin, Uh, Kee-Han, Cho, Jong-Whan, Park, Sang-Woo, Lim, Jae-Ik, Choi, Bang-Sil
• Granted Patent: US 8,040,442 B2
• Time in Patent Office: Days
• US Class Current: 349/96
• CPC Class Codes: G02F 1/13338 Input devices, e.g. touch panels
• CPC Class Codes: G02F 1/133502 Antiglare, refractive index matching layers
• CPC Class Codes: G02F 1/13363 Birefringent elements, e.g. for optical compensation
• CPC Class Codes: G02F 1/133638 Waveplates, i.e. plates with a retardation value of lambda/n
• CPC Class Codes: G02F 2201/50 Protective arrangements
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/045 using resistive elements, e.g. a single continuous surface or two parallel surfaces put in contact

Abstract

A liquid crystal display apparatus comprising a liquid crystal display panel and a touch panel is disclosed. A first transparent electrode is disposed on an upper surface of the liquid crystal display panel for displaying an image. A second transparent electrode is disposed on a lower surface of a retardation member and the second transparent electrode is opposite to the first transparent electrode. Accordingly, the entire thickness of the liquid crystal display apparatus may be decreased, and the manufacturing cost of the liquid crystal display apparatus may be reduced.

Claims

1. A liquid crystal display apparatus comprising:

a liquid crystal display panel for displaying an image, the liquid crystal display panel including a lower substrate and an upper substrate; and

a touch panel using the upper substrate of the liquid crystal display panel as a lower substrate of the touch panel, the touch panel including;

a first retardation member disposed on the upper surface of the liquid crystal display panel;

a first transparent electrode disposed on the first retardation member; and

a second transparent electrode separated from the first transparent electrode by a predetermined distance.

2. The liquid crystal display apparatus of claim 1, further comprising a second retardation member disposed on the first retardation member.

3. The liquid crystal display apparatus of claim 2, wherein the first retardation member is a λ

/4 retardation film, and the second retardation member is a λ

/2 retardation film.

4. The liquid crystal display apparatus of claim 2, wherein a first retardation axis of the first retardation member forms a first angle between about 90°

and about 180°

with respect to a polarizing axis of the first polarizing member, and a second retardation axis of the second retardation member forms a second angle between about 45° and

about 135°

with respect to the polarizing axis of the first polarizing member.

5. The liquid crystal display apparatus of claim 1, further comprising a first polarizing member disposed on the second transparent electrode.

6. The liquid crystal display apparatus of claim 5, further comprising a hard coated film disposed on the first polarizing member to protect the first polarizing member.

7. The liquid crystal display apparatus of claim 5, further comprising a reflection protection film disposed on the first polarizing member to prevent a light from being reflected from a surface of the first polarizing member.

8. The liquid crystal display apparatus of claim 7, wherein the reflection protection film has a Mohs hardness of no less than about 3.

9. The liquid crystal display apparatus of claim 1, wherein the touch panel further includes a spacer disposed between the first and second transparent electrodes, the spacer having a diameter from about 10 μ

m to about 80 μ

m and a height from about 2 μ

m to about 10 μ

m.

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

a third retardation member disposed on a lower surface of the lower substrate of the liquid crystal display panel; and

a fourth retardation member disposed on the third retardation member.

11. The liquid crystal display apparatus of claim 10, wherein the third retardation members are λ

/4 retardation films, and the fourth retardation members are λ

/2 retardation films.

12. The liquid crystal display apparatus of claim 10, further comprising a second polarizing member disposed on a lower surface of the fourth retardation member.

13. The liquid crystal display apparatus of claim 1, wherein the touch panel detects a point where the first transparent electrode is electrically connected to the second transparent electrode to detect a position of an object that touches an outer surface of the touch panel.

14. A liquid crystal display apparatus comprising:

a liquid crystal display panel for displaying an image, the liquid crystal display panel including a lower substrate and an upper substrate; and

a touch panel using the upper substrate of the liquid crystal display panel as a lower substrate of the touch panel, the touch panel including;

a first retardation member disposed on the upper surface of the liquid crystal display panel;

a second retardation member disposed on the first retardation member;

a first transparent electrode disposed on the second retardation member; and

a second transparent electrode separated from the first transparent electrode by a predetermined distance.

15. The liquid crystal display apparatus of claim 14, wherein the first retardation member is a λ

/4 retardation film, and the second retardation member is a λ

/2 retardation film.

16. The liquid crystal display apparatus of claim 15, wherein a first retardation axis of the first retardation member forms a first angle between about 90°

and about 180°

with respect to a polarizing axis of the first polarizing member, and a second retardation axis of the second retardation member forms a second angle between about 45° and

about 135°

with respect to the polarizing axis of the first polarizing member.

17. The liquid crystal display apparatus of claim 14, further comprising a first polarizing member disposed on the second transparent electrode.

18. The liquid crystal display apparatus of claim 17, further comprising a hard coated film disposed on the first polarizing member to protect the first polarizing member.

19. The liquid crystal display apparatus of claim 18, further comprising a reflection protection film disposed on the hard coated film to prevent a light from being reflected from a surface of the first polarizing member.

20. The liquid crystal display apparatus of claim 14, further comprising:

a third retardation member disposed on a lower surface of the lower substrate of the liquid crystal display panel; and

a fourth retardation member disposed on the third retardation member.

21. The liquid crystal display apparatus of claim 20, wherein the third retardation members are λ

/4 retardation films, and the fourth retardation members are λ

/2 retardation films.

22. The liquid crystal display apparatus of claim 20, further comprising a second polarizing member disposed on a lower surface of the fourth retardation member.

23. The liquid crystal display apparatus of claim 20, wherein the first, second, third and fourth retardation members comprise polyarylate.

24. The liquid crystal display apparatus of claim 20, wherein the first, second, third and fourth retardation members comprise polyether sulfone.