Liquid crystal display device and method for driving the same

• US 7,319,448 B2
• Filed: 06/15/2004
• Issued: 01/15/2008
• Est. Priority Date: 06/27/2003
• Status: Active Grant

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Philips LCD Company Limited (LG Display Co., Ltd.)
• Inventors: Kim, Kyong Seok, Lee, Jae Kyun
• Primary Examiner(s): Hjerpe; Richard
• Assistant Examiner(s): Said; Mansour M.
• Application Number:
  US10/866,997
• Publication Number:
  US 20040263743A1
• Time in Patent Office: 1,309 Days
• Field of Search: 345 87- 90, 345 91-103, 345204-206, 345208-210, 345/214, 349/1, 349 42- 43, 349 46- 47, 349141-147
• US Class Current: 345/87
• CPC Class Codes: G02F 1/134363 for applying an electric field parallel to the substrate, i.e. in-plane switching [IPS]
• CPC Class Codes: G09G 2300/0434 Flat panel display in which a field is applied parallel to the display plane
• CPC Class Codes: G09G 3/3614 Control of polarity reversal in general
• CPC Class Codes: G09G 3/3648 using an active matrix G09G3/367 - G09G3/3696 take precedence

Abstract

A liquid crystal display device includes a plurality of pixel regions arranged on a first substrate, a plurality of first electrodes and a plurality of second electrodes individually provided at the pixel regions to form a horizontal electric field, a plurality of gate lines arranged on the first substrate along a horizontal direction to supply scan signals to the pixel regions, a plurality of data lines arranged on the first substrate along a longitudinal direction to supply image information to the pixel regions, a plurality of switching devices each provided at each of the pixel regions and having a first terminal connected to one of the gate lines, a second terminal connected to one of the data lines, and a third terminal connected to a first electrode of the pixel region, a plurality of first common voltage lines supplying a first common voltage to the second electrodes provided at the pixel regions of every odd-numbered first common voltage line, and a plurality of second common voltage lines supplying a second common voltage to second electrodes provided at the pixel regions of every even-numbered second common voltage line, wherein the first terminal of each of the switching devices provided at the pixel regions of a line unit is alternately connected to a N^th gate line and a N+1^th gate line (where N is an integer).

Claims

1. A liquid crystal display device, comprising:

a plurality of pixel regions arranged on a substrate;

a plurality of first electrodes and a plurality of second electrodes individually provided at the pixel regions to form a horizontal electric field;

a plurality of gate lines arranged on the substrate along a horizontal direction to supply scan signals to the pixel regions;

a plurality of data lines arranged on the substrate along a longitudinal direction to supply image information to the pixel regions;

a plurality of switching devices each provided at each of the pixel regions and having a first terminal connected to one of the gate lines, a second terminal connected to one of the data lines, and a third terminal connected to the first electrode of the pixel region;

a plurality of first common voltage lines supplying a first common voltage to the second electrodes provided at the pixel regions of every odd-numbered line; and

a plurality of second common voltage lines supplying a second common voltage to the second electrodes provided at the pixel regions of every even-numbered line,

wherein the first terminal of each of the switching devices provided at the pixel regions of a line unit is alternately connected to a N^th gate line and a N+1^th gate line (where N is an integer).

2. The device according to claim 1, wherein the switching devices include thin film transistors in which a gate electrode is supplied as the first terminal, a source electrode is supplied as the second terminal, and a drain electrode is supplied as the third terminal.

3. The device according to claim 1, wherein the first common voltage lines are arranged parallel to the gate lines and electrically connected to one another, and the second common voltage lines are arranged parallel to the gate lines and electrically connected to one another.

4. The device according to claim 1, wherein the first electrode is a pixel electrode.

5. The device according to claim 1, wherein the second electrode is a common electrode.

6. The device according to claim 1, wherein the first common voltage having a pulse form transited by a unit of frame is supplied to the first common voltage lines and the second common voltage having a pulse form of an inverted first common voltage is supplied to the second common voltage lines.

7. The device according to claim 1, wherein at least one common electrode is formed at a pixel region and is connected to one of the first common voltage lines and the second common voltage lines.

8. The device according to claim 1, wherein the substrate is a TFT array substrate.

9. A method for driving a liquid crystal display employing an in-plane switching (IPS) in which pixel regions are arranged on a substrate and a horizontal electric field is supplied to a liquid crystal layer through a first electrode and a second electrode provided at the pixels, comprising:

alternately connecting first terminals of a plurality of switching devices provided at the pixel regions of a line unit to an N^th gate line and an N+1^th gate line (where N is an integer);

supplying a first common voltage having a pulse form transited by a unit of frame to the second electrodes provided at every odd-numbered line of the pixel regions; and

supplying a second common voltage having a pulse form of an inverted first common voltage to second electrodes provided at every even-numbered line of the pixel regions.

10. The method according to claim 9, wherein the first common voltage is supplied through first common voltage lines arranged parallel to the gate lines corresponding to every odd-numbered line of the pixel regions.

11. The method according to claim 9, wherein the second common voltage is supplied through second common voltage lines arranged parallel to the gate lines corresponding to every even-numbered line of the pixel regions.

12. The method according to claim 9, wherein image information is supplied to the pixel regions by a dot inversion method.

13. The method according to claim 12, wherein the pixel regions are driven as a line inversion.