Transflective liquid crystal display device with asymmetry reflective electrode having a transparent portion facing a main viewing angle

• US 6,380,995 B1
• Filed: 08/05/1999
• Issued: 04/30/2002
• Est. Priority Date: 08/06/1998
• Status: Expired due to Term

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Philips LCD Company Limited (LG Display Co., Ltd.)
• Inventors: Kim, Yong Beom
• Primary Examiner(s): Parker, Kenneth
• Application Number:
  US09/368,414
• Time in Patent Office: 999 Days
• Field of Search: 349/113, 349/114, 349/61, 349/68, 362/26, 362/29, 362/31, 362/27, 362/300, 362/346
• US Class Current: 349/113
• CPC Class Codes: G02F 1/133555 Transflectors

Abstract

A semitransparent reflective type liquid crystal display device is disclosed which comprises: first and second substrates facing to each other and sandwiching a liquid crystal layer therebeween; a backlight on an outer surface of the first substrate; an uneven layer being on an inner surface of the first substrate and having an uneven surface; a reflecting electrode being along the uneven surface and having a transparent portion substantially facing in a main viewing angle direction which is defined as a direction where the user'"'"'s eye is mainly positioned. The transparent portion is in the inclined surface facing in the main viewing angle direction. Accordingly, when operating as a reflective type LCD, the quantity of the main external light which is incident on the transparent portion is decreased to improve the light reflectance.

Claims

1. A semitransparent reflective type liquid crystal display device comprising:

first and second substrates;

a backlight on an outer surface of the first substrate;

an uneven layer on an inner surface of the first substrate and having an uneven surface;

a reflecting electrode along the uneven surface and having a transparent portion substantially facing a main viewing angle; and

a liquid crystal layer between the first and second substrates.

2. The device according to claim 1, wherein the reflecting electrode in the transparent portion is opened.

3. The device according to claim 1, wherein the reflecting electrode has a first inclined surface portion facing the main viewing angle direction and is more steeply inclined than a second inclined surface portion opposite the first inclined surface portion.

4. The device according to claim 1, wherein the reflecting electrode has a plurality of transparent portions and at least two of the transparent portions have different sizes.

5. The device according to claim 1, wherein the reflecting electrode has a plurality of transparent portions, and a first interval between two adjacent transparent portions and a second interval between another two adjacent transparent portions have different sizes.

6. The device according to claim 5, wherein the different interval sizes helps to prevent light interference.

7. The device according to claim 1, wherein the uneven layer has a convex portion having an oval shape, the oval having a long axis that is parallel to the first substrate and perpendicular to the main viewing angle direction.

8. The device according to claim 1, further comprising a transparent electrode in the transparent portion and connected to the reflecting electrode.

9. The device according to claim 1, further comprising a transparent electrode in the transparent portion.

10. The device according to claim 1, further comprising:

a first polarizer between the backlight and the first substrate;

first and second alignment layers on the first and second substrates, respectively;

a second polarizer on the second substrate;

a light phase retardation film on the second substrate; and

a transparent electrode on the second substrate.

11. The device according to claim 10, wherein the transparent electrode acts as a counter electrode to the reflecting electrode.

12. A liquid crystal display device comprising:

first and second substrates;

a light source on a first surface of the first substrate;

an uneven layer on a second surface of the first substrate and having an uneven surface;

a reflecting electrode along the uneven surface and having a transparent portion substantially facing a main viewing angle; and

a liquid crystal layer between the first and second substrates.

14. The device according to claim 12, wherein the reflecting electrode in the transparent portion is opened.

15. The device according to claim 12, wherein the reflecting electrode has a first inclined surface portion facing the main viewing angle direction and is more steeply inclined than a second inclined surface portion opposite the first inclined surface portion.

16. The device according to claim 12, wherein the reflecting electrode has a plurality of transparent portions and at least two of the transparent portions have different sizes.

17. The device according to claim 12, wherein the reflecting electrode has a plurality of transparent portions, and a first interval between two adjacent transparent portions and a second interval between another two adjacent transparent portions have different sizes.

18. The device according to claim 17, wherein the different interval sizes helps to prevent light interference.

19. The device according to claim 12, wherein the uneven layer has a convex portion having an oval shape, the oval having a long axis that is parallel to the first substrate and perpendicular to the main viewing angle direction.

20. The device according to claim 12, further comprising a transparent electrode in the transparent portion and connected to the reflecting electrode.

21. The device according to claim 12, further comprising a transparent electrode in the transparent portion.

13. A semitransparent reflective type liquid crystal display device comprising:

first and second substrates;

a light source on a first surface of the first substrate;

a first polarizer between the light source and the first substrate;

an uneven layer on a second surface of the first substrate and having an uneven surface;

a reflecting electrode along the uneven surface and having a transparent portion substantially facing a main viewing angle;

a first alignment layer over the reflecting electrode;

a second polarizer on a first surface of the second substrate;

a light phase retardation film adjacent the second polarizer;

a transparent electrode on a second surface of the second substrate;

a second alignment layer on the transparent electrode; and

a liquid crystal layer between the first and second substrates.

22. A semitransparent reflective type liquid crystal display device comprising:

first and second substrates;

a backlight on an outer surface of the first substrate;

an uneven layer on an inner surface of the first substrate and having an uneven surface;

a reflecting electrode along the uneven surface and having a transparent portion; and

a liquid crystal layer between the first and second substrates;

wherein the reflecting electrode has a first inclined surface portion facing the main viewing angle direction and is more steeply inclined than a second inclined surface portion opposite the first inclined surface portion.

23. A semitransparent reflective type liquid crystal display device comprising:

first and second substrates;

a backlight on an outer surface of the first substrate;

an uneven layer on an inner surface of the first substrate and having an uneven surface;

a reflecting electrode along the uneven surface and having a transparent portion; and

a liquid crystal layer between the first and second substrates;

wherein the reflecting electrode has a plurality of transparent portions, and a first interval between two adjacent transparent portions and a second interval between another two adjacent transparent portions have different sizes; and

wherein the different interval sizes helps to prevent light interference.

24. A semitransparent reflective type liquid crystal display device comprising:

first and second substrates;

a backlight on an outer surface of the first substrate;

an uneven layer on an inner surface of the first substrate and having an uneven surface;

a reflecting electrode along the uneven surface and having a transparent portion; and

a liquid crystal layer between the first and second substrates;

further comprising a transparent electrode in the transparent portion and connected to the reflecting electrode.

25. A semitransparent reflective type liquid crystal display device comprising:

first and second substrates;

a backlight on an outer surface of the first substrate;

an uneven layer on an inner surface of the first substrate and having an uneven surface;

a reflecting electrode along the uneven surface and having a transparent portion; and

a liquid crystal layer between the first and second substrates;

further comprising a transparent electrode in the transparent portion.

26. A liquid crystal display device comprising:

first and second substrates;

a light source on a first substrate of the first substrate;

an uneven layer on a second surface of the first substrate and having an uneven surface;

a reflecting electrode along the uneven surface and having a transparent portion; and

a liquid crystal layer between the first and second substrates;

wherein the reflecting electrode has a first inclined surface portion facing the main viewing angle direction and is more steeply inclined than a second inclined surface portion opposite the first inclined surface portion.

27. A liquid crystal display device comprising:

first and second substrates;

a light source on a first substrate of the first substrate;

an uneven layer on a second surface of the first substrate and having an uneven surface;

a reflecting electrode along the uneven surface and having a transparent portion; and

a liquid crystal layer between the first and second substrates;

wherein the reflecting electrode has a plurality of transparent portions, and a first interval between two adjacent transparent portions and a second interval between another two adjacent transparent portions have different sizes; and

wherein the different interval sizes helps to prevent light interference.

28. A liquid crystal display device comprising:

first and second substrates;

a light source on a first substrate of the first substrate;

an uneven layer on a second surface of the first substrate and having an uneven surface;

a reflecting electrode along the uneven surface and having a transparent portion; and

a liquid crystal layer between the first and second substrates;

further comprising a transparent electrode in the transparent portion and connected to the reflecting electrode.

29. A liquid crystal display device comprising:

first and second substrates;

a light source on a first substrate of the first substrate;

an uneven layer on a second surface of the first substrate and having an uneven surface;

a reflecting electrode along the uneven surface and having a transparent portion; and

a liquid crystal layer between the first and second substrates;

further comprising a transparent electrode in the transparent portion.