Liquid crystal display and driving method thereof

• US 20030189537A1
• Filed: 06/28/2002
• Published: 10/09/2003
• Est. Priority Date: 04/08/2002
• Status: Active Grant

• Current Assignee: LG Philips LCD Company Limited (LG Display Co., Ltd.)
• Original Assignee: LG Display Co., Ltd.
• Inventors: Yun, Sang Chang
• Granted Patent: US 7,420,533 B2
• Time in Patent Office: Days
• US Class Current: 345/87
• CPC Class Codes: G09G 2300/0439 Pixel structures
• CPC Class Codes: G09G 2330/021 Power management, e.g. power saving
• 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
• CPC Class Codes: G09G 3/3688 suitable for active matrices only

Abstract

A liquid crystal display and a dot inversion driving technique for that liquid crystal display. The liquid crystal display includes a liquid crystal display panel having liquid crystal cells defined by intersections of gate and data lines. Each liquid crystal cell includes a thin film transistor. Those thin film transistors are connected in a zigzag pattern to the gate lines. Pixel voltage signals are applied in a line inversion fashion to the liquid crystal cells such that the pixel voltage signal polarities (referenced to a common electrode) are inverted in every horizontal period. The common electrode can be an AC voltage that changes in each horizontal period.

Claims

1. A liquid crystal display, comprising:

a liquid crystal display panel having liquid crystal cells defined between intersecting gate lines and data lines;

thin film transistors connected in a zigzag pattern to the gate lines;

a common electrode disposed adjacent the liquid crystal display panel;

liquid crystal disposed between the common electrode disposed and the liquid crystal display panel; and

a liquid crystal display panel driver for applying pixel voltage signals to the data lines, wherein the pixel voltage signals on each data line has the same polarity in a horizontal period.

2. The liquid crystal display according to claim 1, wherein odd-numbered liquid crystal cells of the ith horizontal line (wherein i is an integer) are connected to the ith gate line, and wherein even-numbered liquid crystal cells of the ith horizontal line are connected to the (i+1)th gate line.

3. The liquid crystal display according to claim 1, wherein even-numbered liquid crystal cells of the liquid crystal cells on the ith horizontal line (wherein i is an integer) are connected to the ith gate line, and wherein odd-numbered liquid crystal cells on the ith horizontal line are connected to the (i+1)th gate line.

4. The liquid crystal display according to claim 1, wherein the liquid crystal display panel driver includes:

a gate driver for sequentially driving the gate lines;

a data driver for converting input pixel data into pixel voltage signals used in a line inversion system, wherein the pixel voltage signals are applied to the data lines;

a common voltage generator for supplying a common voltage to the common electrode; and

a timing controller for controlling the gate driver and the data driver, and for combining pixel data in a horizontal period with pixel data from a previous horizontal period to produce combined input pixel data.

5. The liquid crystal display according to claim 4, wherein the timing controller combines odd-numbered pixel data of a horizontal period with even-numbered pixel data from a previous horizontal period, to produce the combined input pixel data, wherein the even-numbered pixel data is delayed by one horizontal period.

6. The liquid crystal display according to claim 4, wherein the timing controller combines even-numbered pixel data of a horizontal period with odd-numbered pixel data from a previous horizontal period, to produce the combined input pixel data, wherein the odd-numbered pixel data is delayed by one horizontal period.

7. The liquid crystal display according to claim 1, wherein the liquid crystal display panel driver includes:

a gate driver for sequentially driving the gate lines;

a data driver for combining pixel data in a current horizontal period with pixel data in a previous horizontal period to produce combined pixel data, the data driver further for converting the combined pixel data into pixel voltage signals that are applied to the data lines in every horizontal period;

a common voltage generator for supplying a common voltage to the common electrode; and

a timing controller for controlling the gate driver and the data driver, and for supplying pixel data to the data driver.

8. The liquid crystal display according to claim 7, wherein the data driver combines odd-numbered pixel data of one horizontal line with even-numbered pixel data that is delayed by one horizontal period to produce the combined pixel data.

9. The liquid crystal display according to claim 7, wherein the data driver combines even-numbered pixel data of one horizontal line with odd-numbered pixel data that is delayed by one horizontal period to produce the combined pixel data.

10. The liquid crystal display according to claim 7, wherein the data driver includes:

a shift register array for applying sequential sampling signals;

a latch array for latching and outputting pixel data in response to the sequential sampling signals;

a digital-to-analog converter array for converting pixel data into pixel voltage signals;

a buffer array for buffering and outputting buffered pixel voltage signals; and

a delay array for delaying odd-numbered pixel data by one horizontal period.

11. The liquid crystal display according to claim 7, wherein the data driver includes:

a shift register array for applying sequential sampling signals;

a latch array for latching and outputting pixel data in response to the sequential sampling signals;

a digital-to-analog converter array for converting pixel data into pixel voltage signals;

a buffer array for buffering and outputting buffered pixel voltage signals; and

a delay array for delaying even-numbered pixel data by one horizontal period.

12. The liquid crystal display according to claim 1, wherein the liquid crystal display panel driver includes:

a gate driver for sequentially driving the gate lines;

a data driver for converting combined pixel data into pixel voltage signals that are applied as pixel voltage signals to the data lines;

a common voltage generator for supplying an AC common voltage to the common electrode; and

a timing controller for controlling the gate driver and the data driver and for combining pixel data in a current horizontal period with pixel data in a previous horizontal period to produce combined pixel data.

13. The liquid crystal display according to claim 1, wherein the liquid crystal display panel driver includes:

a gate driver for sequentially driving the gate lines;

a data driver for combining pixel data in a current horizontal period with pixel data from a previous horizontal period to produce combined pixel voltage signals that are applied to the data lines in every horizontal period;

a common voltage generator for supplying an AC voltage to the common electrode; and

a timing controller for controlling the gate driver and the data driver and for applying pixel data to the data driver.

14. A method of driving a liquid crystal display, comprising the steps of:

combining pixel data in a current horizontal period with pixel data in a previous horizontal period to produce combined pixel data in every horizontal period; and

applying the combined pixel data to liquid crystal cells that are connected together in a zigzag pattern.

15. The method according to claim 14, wherein, said step of combining pixel data includes combining odd-numbered pixel data of a current horizontal line with even-numbered pixel data that is delayed by one horizontal period.

16. The method according to claim 14, wherein, said step of combining pixel data includes combining even-numbered pixel data of a current horizontal line with odd-numbered pixel data that is delayed by one horizontal period.