IP Library Granted Patent US 8,456,405
Granted Patent B2
US 8,456,405 · App. 12/623,159 · Granted Jun 4, 2013

Liquid crystal display device and driving method of the same

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Quick Facts
Patent No.
US 8,456,405
App. No.
12/623,159
Granted
Jun 4, 2013
Kind
B2
Abstract

A liquid crystal display device and driving method therefor are disclosed. The device includes a plurality of signal lines that apply different gray scale voltages to each of the pixels. A driving circuit is provided to generate the gray scale voltages to be applied to the pixels. In operation, the driving circuit applies the first gray scale voltage at intervals of the horizontal scanning time within a display period. The second gray scale voltage is output by a number of times that is not smaller than twice and not greater than (M-N) times at intervals of the horizontal scanning time from the beginning of the vertical retrace interval. The second gray scale voltage is then stopped until completion of the vertical retrace interval.

Claims (31)

1. A driving method of a liquid crystal display device having a plurality of pixels, a plurality of signal lines which apply a gray scale voltage to each of the pixels, and a driving circuit which outputs an output signal for changing the gray scale voltage applied to each of the signal lines, the method comprising the steps of:

outputting the output signal from the driving circuit during a vertical retrace interval; and

stopping the outputting of the output signal from the driving circuit until completion of the vertical retrace interval;

wherein an interval from a last outputting of the output signal within the vertical retrace interval until a first outputting of the output signal at a next frame is longer than a horizontal scanning time.

2. A driving method of a liquid crystal display device according to claim 1 , wherein the output signal is outputted from a beginning of the vertical retrace interval.

3. A driving method of a liquid crystal display device according to claim 1 , wherein the output signal is outputted within the vertical retrace interval in synchronism with a regular horizontal synchronizing signal.

4. A driving method of a liquid crystal display device according to claim 1 , wherein the output signal is outputted within the vertical retrace interval in synchronism with an internally generated horizontal synchronizing signal.

5. A driving method of a liquid crystal display device according to claim 1 , wherein a polarity of the gray scale voltage is inverted at least once within the vertical retrace interval.

6. A driving method of a liquid crystal display device according to claim 1 , wherein the gray scale voltage within the vertical retrace interval is a gray scale voltage for displaying white or black.

7. A liquid crystal display device comprising:

a plurality of pixels;

a plurality of signal lines which apply a gray scale voltage to each of the pixels; and

a driving circuit which outputs an output signal for changing the gray scale voltage applied to each of the signal lines,

wherein the driving circuit:

outputs the output signal during a vertical retrace interval, and

stops the outputting of the output signal from the driving circuit until completion of the vertical retrace interval, and

wherein an interval from a last outputting of the output signal within the vertical retrace interval until a first outputting of the output signal at a next frame is longer than a horizontal scanning time.

8. A liquid crystal display device according to claim 7 , wherein the output signal is outputted from a beginning of the vertical retrace interval.

9. A liquid crystal display device according to claim 7 , wherein a polarity of the gray scale voltage is inverted at least once within the vertical retrace interval.

10. A liquid crystal display device according to claim 7 , wherein the gray scale voltage within the vertical retrace interval is a gray scale voltage for displaying white or black.

11. A liquid crystal display device comprising:

a plurality of pixels;

a plurality of signals lines which apply a gray scale voltage to each of the pixels; and

a driving circuit which outputs the gray scale voltage to a plurality of pixels,

wherein the driving circuit:

outputs the gray scale voltage to each of the signal lines during a vertical retrace interval, and

stops the outputting of the gray scale voltage from the driving circuit to each of the signal lines until completion of the vertical retrace interval, and

wherein an interval from a last outputting of the gray scale voltage within the vertical retrace interval until a first outputting of the gray scale voltage at a next frame is longer than a horizontal scanning time.

12. A liquid crystal display device according to claim 11 , wherein the gray scale voltage is outputted from a beginning of the vertical retrace interval.

13. A liquid crystal display device according to claim 11 , wherein a polarity of the gray scale voltage is inverted at least once within the vertical retrace interval.

14. A liquid crystal display device according to claim 11 , wherein the gray scale voltage within the vertical retrace interval is a gray scale voltage for displaying white or black.

Assignments (4)
NUNC PRO TUNC ASSIGNMENT Recorded Nov 17, 2023
From: PANASONIC LIQUID CRYSTAL DISPLAY CO., LTD.
To: PANASONIC INTELLECTUAL PROPERTY CORPORATION OF AMERICA
Reel/Frame 065615/0327 →
COMPANY SPLIT PLAN TRANSFERRING FIFTY (50) PERCENT SHARE OF PATENTS AND PATENT APPLICATIONS Recorded Dec 12, 2011
From: HITACHI DISPLAYS, LTD.
To: IPS ALPHA SUPPORT CO., LTD.
Reel/Frame 027362/0466 →
COMPANY SPLIT PLAN TRANSFERRING ONE HUNDRED (100) PERCENT SHARE OF PATENT AND PATENT APPLICATIONS Recorded Dec 12, 2011
From: HITACHI, LTD.
To: HITACHI DISPLAYS, LTD.
Reel/Frame 027362/0612 →
MERGER/CHANGE OF NAME Recorded Dec 12, 2011
From: IPS ALPHA SUPPORT CO., LTD.
To: PANASONIC LIQUID CRYSTAL DISPLAY CO., LTD.
Reel/Frame 027363/0315 →