LIQUID CRYSTAL DISPLAY

• US 20080088575A1
• Filed: 11/29/2007
• Published: 04/17/2008
• Est. Priority Date: 03/07/2003
• Status: Active Grant

• Current Assignee: HannStar Display Corporation
• Original Assignee: HannStar Display Corporation
• Inventors: Shih, Po-Sheng, Lee, Seok-Lyul
• Granted Patent: US 7,800,579 B2
• Time in Patent Office: Days
• US Class Current: 345/103
• CPC Class Codes: G09G 2320/0247 Flicker reduction other than flicker reduction circuits used for single beam cathode-ray tubes
• 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 3/3655 Details of drivers for counter electrodes, e.g. common electrodes for pixel capacitors or supplementary storage capacitors

Abstract

A liquid crystal display replaces the common electrodes of a conventional LCD with a plurality of switch electrodes. The plurality of switch electrodes is grouped into several switch electrode sets. Each of the switch electrode sets'"'"' potential is modulated by a different driving circuit. The driving circuits can also separately modulate the potentials of the switch electrode sets according to the scanning sequence of the LCD.

Claims

1. A driving method for a display apparatus, the display apparatus comprising a plurality of data lines, a plurality of scanning lines, a plurality of conductive lines crossing the plurality of data lines, and a plurality of pixels positioned at a plurality of matrix-arranged unit areas enclosed by the scanning lines and the data lines, each of the plurality of pixels includes a thin film transistor and a liquid crystal capacitor, comprising:

providing a first modulation signal to a first group of the conductive lines; and

providing a second modulation signal to a second group of the conductive lines.

2. The driving method according to claim 1, wherein the first modulation signal and the second modulation signal are separately provided by a first modulation source and a second modulation source.

3. The driving method according to claim 1, wherein the first modulation signal and the second modulation signal comprise square pulses opposite in phase.

4. The driving method according to claim 1, wherein the frequency of each of the first modulation signal and the second modulation signal is synchronized with a frame frequency of the display apparatus.

5. The driving method according to claim 1, wherein the frequency of each of the first modulation signal and the second modulation signal is synchronized with multiple times of a scanning frequency of the plurality of scanning lines.

6. The driving method according to claim 1, wherein the first group of conductive lines are respectively coupled to at least one first transistor, and the second group of conductive lines are respectively coupled to at least one second transistor.

7. The driving method according to claim 6, wherein each of the first and second transistors has a gate electrode electrically connected to one of the scanning lines, a source electrode electrically connected to the plurality of first conductive lines or the plurality of second conductive lines, and a drain electrode electrically connected to a modulation signal source.

8. The driving method according to claim 7, wherein the drain electrodes of the first transistors are connected to the first modulation source, and the drain electrodes of the second transistors are connected to the second modulation source.

9. The driving method according to claim 1, further comprising a potential modulation module electrically connected to the first group and the second group of conductive lines.

10. The driving method according to claim 9, wherein the potential modulation module outputs square pulses as potential modulation signals to the first group and the second group of conductive lines, and the potential modulation signals respectively applied to two adjacent the first group and the second group of conductive lines are opposite in phase.

11. The driving method according to claim 1, wherein the first group of conductive lines and the second group of conductive lines are positioned alternatively to each other.

12. The driving method according to claim 1, wherein the set of the first group of conductive lines are positioned adjacent to the set of the second group of conductive lines.

13. The driving method according to claim 1, wherein each of the first group of conductive lines is electrically connected to a first shift register, and each of the second group of conductive lines is electrically connected to a second shift register.

14. The driving method according to claim 13, further comprising a signal source electrically connected to one of the first shift registers.

15. The driving method according to claim 13, wherein the one of the first shift registers shorts to a first conductive line at the first row.

16. The driving method according to claim 13, wherein an output terminal of the first shift register at the first row is connected to an input terminal of the second shift register next to the first shift register.

17. The driving method according to claim 13, wherein each of the first and second shift registers has a first potential pin shorting to a first external potential source, a second potential pin shorting to a second external potential source, and a clock pin shorting to the corresponding scanning line.

18. The driving method according to claim 13, wherein the output terminal of each of the first and second shift registers is at a first potential when the clock pin is selected by the scanning line and meanwhile the input terminal of each of the first and second shift registers is at a second potential.

19. A driving method for a liquid crystal display apparatus, the display apparatus comprising a plurality of data lines, a plurality of scanning lines, a plurality of conductive lines crossing the plurality of data lines, and a plurality of pixels positioned at a plurality of matrix-arranged unit areas enclosed by the scanning lines and the data lines, each of the plurality of pixels including a thin film transistor and a liquid crystal capacitor, comprising:

modulating a first group of the conductive lines by a first modulation signal; and

modulating a second group of the conductive lines by a second modulation signal;

wherein the first modulation signal and the second modulation signal are opposite in phase, and are synchronized with multiple times of a scanning frequency of the plurality of scanning lines.

20. The driving method according to claim 19, wherein the frequency of each of the first modulation signal and the second modulation signal is equal to a frame frequency of the display apparatus.

21. A driving method for a liquid crystal display apparatus, the display apparatus comprising a plurality of data lines, a plurality of scanning lines, a plurality of conductive lines crossing the plurality of data lines, and a plurality of pixels positioned at a plurality of matrix-arranged unit areas enclosed by the scanning lines and the data lines, each of the plurality of pixels including a thin film transistor and a liquid crystal capacitor, comprising:

connecting a first switch to a first conductive line of the conductive lines;

connecting a second switch to a second conductive line of the conductive lines; and

modulating the first conductive line and the second conductive line separately by a first modulation signal and a second modulation signal;

wherein the first modulation signal and the second modulation are opposite in phase, and are synchronized with multiple times of a scanning frequency of the plurality of scanning lines.

22. The driving method according to claim 21, wherein the frequency of each of the first modulation signal and the second modulation signal is equal to a frame frequency of the display apparatus.