Liquid crystal display device and the method thereof

• US 7,821,608 B2
• Filed: 12/21/2006
• Issued: 10/26/2010
• Est. Priority Date: 12/28/2005
• Status: Active Grant

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Display Co., Ltd.
• Inventors: Yuichi, Momoi, Hidefumi, Yoshida, Hidefumi, Yamashita, Kaoru, Furuta, Shinichi, Kimura, Kazuyoshi, Nagayama
• Primary Examiner(s): Rahll; Jerry T
• Application Number:
  US11/642,955
• Publication Number:
  US 20070200989A1
• Time in Patent Office: 1,405 Days
• Field of Search: 349/144, 349/142
• US Class Current: 349/144
• 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 1/133753 with different alignment orientations or pretilt angles on a same surface, e.g. for grey scale or improved viewing angle
• CPC Class Codes: G02F 1/134309 characterised by their geometrical arrangement
• 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

Abstract

Disclosed herein is a liquid crystal display device which can control a viewing angle in up/down and left/right directions without need of forming white subpixels. In the liquid crystal display device which includes a first region having liquid crystal molecules aligned in a slanted direction, and a second region having the liquid crystal molecules aligned in up and down directions or in left and right directions. Voltage is independently applied to the second region from the first region.

Claims

1. A liquid crystal display having a plurality of pixels, each pixel comprising:

a first region having liquid crystal molecules aligned in a slanted direction; and

a second region including an up and down control region having liquid crystal molecules aligned in up and down directions or a left and right control region having liquid crystal molecules aligned in left and right directions,

wherein voltage is independently applied to the first region and the second region so that the liquid crystal molecules in the first region is independent controllable from the liquid crystal molecules of the second region, and

wherein each of the pixels is one of red, green and blue subpixels.

2. The device according to claim 1, wherein voltage which is turned ON and OFF periodically is applied to the second region.

3. The device according to claim 1, wherein alternating current voltage whose frequency is about 30 Hz and less is applied to the second region.

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

a common line across a middle portion of the first region in each of the pixels.

5. The device according to claim 1, wherein the first region has at least one of a first slit and a first protrusion in a pixel electrode in a slanted direction, and the second region has the up and down control region having one of a second slit and a second protrusion in a pixel electrode in the left and right directions.

6. The device according to claim 5, wherein the first region further includes a plurality of small slits perpendicular to the first slit, wherein a width of the small slits is narrower than that of the first slit.

7. The device according to claim 5, wherein the up and down control region of the second region further includes a plurality of small slits in the pixel electrode in the up and down directions, wherein a width of the small slits is narrower than that of the first or second slit.

8. The device according to claim 7, wherein the small slits have a width of about 5 microns and less and a gap of about 5 microns and less at a surface.

9. The device according to claim 1, wherein the first region has one of a first slit and a first protrusion in a pixel electrode in a slanted direction, and the second region has the left and right control region having one of a second slit and a second protrusion in a pixel electrode in the up and down directions.

10. The device according to claim 9, wherein the first region further includes a plurality of small slits perpendicular to the first slit, wherein a width of the small slits is narrower than that of the first slit.

11. The device according to claim 9, wherein the left and right control region of the second region further includes a plurality of small slits in the pixel electrode in the left and right directions, wherein a width of the small slits is narrower than that of the first or second slit.

12. The device according to claim 11, wherein the small slits have a width of about 5 microns and less and a gap of about 5 microns and less at a surface.

13. The device according to claim 1, wherein voltage which is controlled to have a desired value is applied to the second region.

14. The device according to claim 1, wherein alternating current voltage of a variable period is applied to the second region.

15. The device according to claim 1, wherein alternating current voltage whose frequency is 60 Hz and less is applied to the second region.

16. The device according to claim 1, wherein alternating current voltage which varies a center voltage is applied to the second region.

17. The device according to claim 1, wherein the up and down control region and the left and right control region are arranged in the display screen to form a predetermined pattern.

18. The device according to claim 1, wherein voltage which varies periodically is applied to the second region.

19. The device according to claim 1, wherein each of the pixels further includes a metal line which is formed substantially in parallel with a gate electrode by using a gate layer in the second region and connected to a pixel electrode formed at the second region through a contact hole.

20. The device according to claim 19, wherein the metal line extends across a middle portion of the second region in each of the pixels.

21. The device according to claim 19, wherein the contact hole is formed by a process of forming a hole to contact a pixel electrode of the first region and a source electrode.

22. The device according to claim 19, wherein the metal line is provided at a position opposite to a mounting position of a gate driver to apply voltage.

23. A method for fabricating of a liquid crystal display having a plurality of pixels, comprising:

forming a first region having liquid crystal molecules aligned in a slanted direction; and

forming a second region including an up and down control region having the liquid crystal molecules aligned in up and down directions or a left and right control region having liquid crystal molecules aligned in left and right directions,

wherein voltage is independently applied to the first region and the second region so that the liquid crystal molecules in the first region is independent controllable from the liquid crystal molecules of the second region, and

wherein each of the pixels is one of red, green and blue (RGB) sub-pixels.