Liquid crystal display device and method of driving the same

• US 20070146606A1
• Filed: 12/21/2006
• Published: 06/28/2007
• 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: Yamashita, Hidefumi
• Granted Patent: US 7,667,808 B2
• Time in Patent Office: Days
• US Class Current: 349/141
• 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 1/134381 Hybrid switching mode, i.e. for applying an electric field with components parallel and orthogonal to the substrates

Abstract

A liquid crystal display device includes a first electrode and a second electrode on a first substrate, wherein a horizontal electric field is generated between the first and second electrodes, and a third electrode on a second substrate, wherein a longitudinal electric field is generated between the third electrode and the first and second electrodes. In the liquid crystal display device, control of a wide viewing angle and a narrow viewing angle is enabled.

Claims

1. A liquid crystal display device comprising:

a first electrode and a second electrode on a first substrate, wherein a horizontal electric field is generated between the first and second electrodes; and

a third electrode on a second substrate facing the first substrate, wherein a longitudinal electric field is generated between the third electrode and the first and second electrodes.

2. The device according to claim 1, wherein the second substrate further includes a dielectric film on the third electrode.

3. The device according to claim 1, wherein a wide viewing angle mode is switched to a narrow viewing angle mode by adjusting a voltage applied to the third electrode.

4. The device according to claim 3, wherein the voltage applied to the third electrode is substantially a same voltage as that applied to the first electrode.

5. The device according to claim 3, wherein the voltage applied to the third electrode is higher than a voltage applied to the first electrode.

6. The device according to claim 1, wherein the first substrate further includes an insulator film interposed between the first and second electrodes.

7. The device according to claim 6, wherein the second substrate further includes a dielectric film on the third electrode.

8. The device according to claim 6, wherein a wide viewing angle mode is switched to a narrow viewing angle mode by adjusting a voltage applied to the third electrode.

9. The device according to claim 8, wherein the voltage applied to the third electrode is substantially a same voltage as that applied to the first electrode.

10. The device according to claim 8, wherein the voltage applied to the third electrode is higher than a voltage applied to the first electrode.

11. The device according to claim 1, wherein the liquid crystal display device is one of an in plane switching mode and a fringe field switching mode.

12. A method of driving a liquid crystal display device, comprising:

forming a first electrode and a second electrode on a first substrate to generate a first electric field;

forming a third electrode on a second substrate to generate a second electric field; and

controlling a viewing angle by adjusting a voltage applied to the third electrode.

13. The method according to claim 12, wherein the viewing angle is switched from a wide viewing angle mode to a narrow viewing angle mode by adjusting the voltage applied to the third electrode.

14. The method according to claim 12, wherein a same voltage as one of the voltages of the first and second electrodes is applied to the third electrode.

15. The method according to claim 12, wherein a voltage higher than one of the voltages of the first and second electrodes is applied to the third electrode.

16. The method according to claim 12, wherein the liquid crystal display device of the method of driving includes one of an in plane switching mode and a fringe field switching mode.