Liquid crystal display device

• US 20070176872A1
• Filed: 12/28/2006
• Published: 08/02/2007
• Est. Priority Date: 12/28/2005
• Status: Active Grant

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Philips LCD Company Limited (LG Display Co., Ltd.)
• Inventors: Kazuyoshi, Nagayama, Yuichi, Momoi
• Granted Patent: US 8,233,124 B2
• Time in Patent Office: Days
• US Class Current: 345/90
• CPC Class Codes: G02F 1/134363 for applying an electric field parallel to the substrate, i.e. in-plane switching [IPS]
• CPC Class Codes: G02F 1/134372 for fringe field switching [FFS] where the common electrode is not patterned
• CPC Class Codes: G09G 2300/0426 Layout of electrodes and connections
• CPC Class Codes: G09G 2300/0443 with several sub-pixels for the same colour in a pixel, not specifically used to display gradations G09G3/364 takes precedence
• CPC Class Codes: G09G 2310/0235 Field-sequential colour display
• CPC Class Codes: G09G 3/3406 Control of illumination source illumination devices structurally associated with liquid crystal cells G02F1/1336

Abstract

A liquid crystal display device is disclosed, which can control a viewing angle in vertical and horizontal directions without forming a specific liquid crystal display panel, the liquid crystal display device comprising a display screen including a plurality of color pixels and liquid crystal molecules; and a viewing-angle control pixel controlling the liquid crystal molecules, an alignment direction of the liquid crystal molecules being inclined to a vertical or horizontal direction in the display screen, wherein the viewing-angle control pixel is formed independently of RGB pixels, to thereby control the viewing angle in the horizontal and vertical directions.

Claims

1. A liquid crystal display device, comprising:

a display screen including a plurality of color pixels and viewing angle control pixels, each of the color pixels and the viewing angle control pixels including liquid crystal molecules,

an alignment direction of the liquid crystal molecules being inclined to a vertical or horizontal direction with respect to the display screen.

2. The device of claim 1, further comprising a color filter layer on a substrate over the color pixels wherein the color filter layer is not formed over the viewing-angle control pixels.

4. The device of claim 1, wherein the liquid crystal molecules in the viewing angle control pixels are aligned to have a predetermined transmittance in the presence of a viewing angle control signal.

5. The device of claim 4, wherein the viewing-angle control signal is commonly applied to the plurality of viewing-angle control pixels in the display screen without a switching element.

6. The device of claim 4, further comprising a viewing-angle control voltage adjuster that adjusts a center value of the viewing-angle control signal to be substantially identical to a common voltage of the color pixels.

7. The device of claim 4, wherein the viewing-angle control signal is synchronized with a signal of the color pixel.

8. The device of claim 1, further comprising:

a color pixel driver for applying a signal to the color pixels, and is formed at one side of the display screen; and

a viewing-angle control pixel driver for applying a signal to the viewing-angle control pixel, and is at a side of the display screen opposite the color pixel driver.

9. The device of claim 8, further comprising a viewing-angle control voltage adjuster that adjusts a center value of the viewing-angle control signal to be identical to a common voltage of the color pixel.

10. The device of claim 8, wherein the viewing-angle control signal is synchronized with a signal of the color pixel.

11. The device of claim 1, wherein the liquid crystal display device includes a fringe field switching mode.

3. The device of claim l, wherein the liquid crystal molecules in the viewing angle control pixels are aligned to form a predetermined shape in the presence of a viewing angle control signal.

12. A liquid crystal display device, comprising:

a plurality of color pixels, each color pixel including;

liquid crystal molecules therein;

at least one common electrode; and

a pixel electrode;

a plurality of viewing angle control pixels, each viewing angle control pixel including;

liquid crystal molecules therein;

at least one common electrode; and

a pixel electrode;

wherein the common electrode in the viewing angle control pixels extends in a direction different from the at least one common electrode in the color pixels such that an alignment of the liquid crystal molecules in the viewing angle control pixels is controllable in a vertical or horizontal direction.

13. The device of claim 12, wherein the liquid crystal molecules in the viewing angle control pixel have an initial alignment inclined in a vertical or horizontal direction.

14. The device of claim 12, wherein the liquid crystal molecules in the viewing angle control pixels move in the presence of an applied electric field to display white to a side direction.

15. The device of claim 12, wherein the liquid crystal molecules in the viewing angle control pixels move in the presence of an applied electric field to display a predetermined shape to a side direction.

16. The device of claim 12, further comprising:

data lines and gate lines connected to the color pixels to control display of the color pixels, wherein each color pixel is connected to a respective data line and gate line through a thin film transistor as a switching device; and

control lines connected directly to viewing angle control pixels for applying a viewing angle control signal.

17. The device of claim 16, further comprising a viewing angle control voltage adjuster that adjusts a center value of the view angle control signal to be substantially the same as a common voltage of the color pixels.

18. The device of claim 12, wherein the common electrode in the viewing angle control pixel extends in a horizontal direction.

19. The device of claim 12, wherein the common electrode in the viewing angle control pixel extends in a vertical direction.

20. The device of claim 12, wherein the common electrode in the color pixel has a “

V”

shape.

21. The device of claim 12, wherein the common electrode in the color pixel has a “

<

”

shape.

22. The device of claim 12, wherein the viewing angle control pixels are aligned to form a predetermined shape in the liquid crystal display device.

23. The device of claim 22, wherein the viewing angle control pixels includes fist viewing angle control pixels and second viewing angle control pixels,

wherein the first viewing angle conteol pixels and second viewing angle control pixels aligned to form a predetermined shape in the liquid crystal display device.