Liquid crystal display device and driving device thereof, and method for driving liquid crystal display device

• US 20050122305A1
• Filed: 12/01/2004
• Published: 06/09/2005
• Est. Priority Date: 12/03/2003
• Status: Active Grant

• Current Assignee: Unified Innovative Technology, LLC
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Murao, Masayuki, Mizumaki, Hidetaka
• Granted Patent: US 7,420,538 B2
• Time in Patent Office: Days
• US Class Current: 345/101
• CPC Class Codes: G02F 1/133382 Heating or cooling of liquid crystal cells other than for activation, e.g. circuits or arrangements for temperature control, stabilisation or uniform distribution over the cell
• CPC Class Codes: G09G 2320/0233 Improving the luminance or brightness uniformity across the screen
• CPC Class Codes: G09G 2320/0252 Improving the response speed
• CPC Class Codes: G09G 2320/0261 in the context of movement of objects on the screen or movement of the observer relative to the screen
• CPC Class Codes: G09G 2320/041 Temperature compensation
• CPC Class Codes: G09G 2340/16 Determination of a pixel data signal depending on the signal applied in the previous frame
• CPC Class Codes: G09G 3/3648 using an active matrix G09G3/367 - G09G3/3696 take precedence

Abstract

A liquid crystal display device of the present invention includes (i) a temperature sensor provided in at least one of pixels in a displaying area of a display panel, (ii) a lead line buried in the display panel, for transmitting a detection signal from the temperature sensor to a vicinity of the display panel, (iii) a temperature measurement control section for measuring a pixel temperature based on the detection signal transmitted from the temperature sensor, (iv) a data signal line driving section for outputting the data signal to the data signal lines in accordance with the pixel temperature measured in the temperature measurement control section. Further, the liquid crystal display device of the present invention includes (i) a plurality of data generating sections for generating data signals of the different output levels based on an inputted video signal and a video signal that is at least one frame earlier than the inputted video signal, (ii) a data generating section containing section for containing therein the plurality of the data generating sections, and (iii) a memory for use in selecting one of the data generating sections on a line-by-line basis for the respective scan signal lines.

Claims

1. A liquid crystal display device including a plurality of scan signal lines, a plurality of data signal lines to which video signals are supplied as data signals, and a displaying section including pixels arranged in a matrix manner, the pixels respectively connected, via switching sections, with the scan signal lines and the data signal lines corresponding to intersecting points thereof, the liquid crystal display device comprising:

a temperature sensor provided in at least one of the pixels in a displaying region of the displaying section;

a lead line provided unnoticeably in the displaying section, for transmitting a detection signal from the temperature sensor to a peripheral section of the displaying section;

a temperature measurement control section for measuring a temperature based on the detection signal transmitted from the temperature sensor; and

a data signal line driving section for outputting the data signal to the data signal lines in a manner based on the temperature measured in the temperature measurement control section.

3. The liquid crystal display device as set forth in claim 1, comprising:

spare lines respectively corresponding to the data signal lines and branched to be connected with the data signal lines in such a manner that a ladder-like shape is formed with the spare lines and the data signal lines, the spare lines being for ensuring transmission of the data signal even if breaking occurs in a data signal line,

the spare lines also functioning as the lead line.

4. The liquid crystal display device as set forth in claim 1, wherein the temperature sensor is a thermister type sensor that has been built in the pixels by carrying out film formation to form element films from which the temperature sensor is formed.

5. The liquid crystal display device as set forth in claim 1, wherein:

the data-signal-line driving section supplies, to a data signal line, a data signal voltage larger than a target data signal voltage that corresponds to a gradation value indicated by the video signal.

6. The liquid crystal display device as set forth in claim 1, wherein the temperature sensor is provided in a vicinity of a scan signal line or in a vicinity of a data signal line.

7. The liquid crystal display device as set forth in claim 6, wherein the temperature sensor is shielded by a shielding member.

8. The liquid crystal display device as set forth in claim 1, wherein:

a plurality of temperature sensors are provided in the pixels in an area excluding a top H/4 of the displaying region and a bottom H/4 of the displaying region, where H is a height of the displaying region; and

the temperature is an average of a plurality of the detection signals transmitted from the plurality of the temperature sensor, the average calculated by the temperature measurement control section.

9. The liquid crystal display device as set forth in claim 8, wherein:

the plurality of the temperature sensor are dispersed 2-dimensionally over displaying area; and

the plurality of the temperature sensor are provided at substantially equal intervals in a horizontal direction of the displaying area.

10. The liquid crystal display device as set forth in claim 8, wherein the data signal lines are arranged at substantially equal intervals in that part of the display region which includes positions of the temperature sensors.

11. The liquid crystal display device as set forth in claim 8;

wherein the plurality of the temperature sensor are arranged at substantially equal intervals in a vertical direction of the displaying area.

12. The liquid crystal display device as set forth in claim 9, wherein the plurality of the temperature sensor are arranged at substantially equal intervals in a vertical direction of the displaying area.

13. The liquid crystal display device as set forth in claim 10, wherein the plurality of the temperature sensor are arranged at substantially equal intervals in a vertical direction of the displaying area.

2. A liquid crystal display device including a plurality of scan signal lines, a plurality of data signal lines to which video signals are supplied as data signals, and a displaying section including pixels arranged in a matrix manner, the pixels respectively connected, via switching sections, with the scan signal lines and the data signal lines corresponding to intersecting points thereof, the liquid crystal display device comprising:

a temperature sensor provided in at least one of the pixels in a displaying region of the displaying section;

a temperature measurement control section provided in a peripheral section of the displaying section, for measuring a pixel temperature based on the detection signal transmitted from the temperature sensor;

a lead line for transmitting a detection signal from the temperature sensor to the temperature measurement control section, the lead line unnoticeably provided in the displaying section; and

data signal line driving section for outputting the data signal to the data signal lines in accordance with the temperature measured in the temperature measurement control section.

14. A liquid crystal display device including a plurality of scan signal lines, a plurality of data signal lines to which video signals are supplied as data signals appropriate for grey scale display, and a displaying section including pixels arranged in a matrix manner, the pixels respectively connected, via switching sections, with the scan signal lines and the data signal lines corresponding to intersecting points thereof, the liquid crystal display device comprising:

a plurality of data generating sections for generating the data signals;

a data generating section containing section for containing therein the plurality of data generating sections, and

a data generating section selecting section for selecting one of the data generating sections on a line-by-line basis for the respective scan signal lines.

15. The liquid crystal display device as set forth in claim 14, wherein:

the plurality of the data generating sections are configured to generate the data signals based on an inputted video signal and a video signal that is at least one frame earlier than the inputted video signal; and

the plurality of the data generating sections are configured to generate the data signals of the different output levels, based on difference between the video signal and the inputted video signal of the at least one frame earlier than the inputted video signal.

16. The liquid crystal display device as set forth in claim 14, wherein the respective scan signal lines receives the data signals supplied from the data generating sections selected on the line-by-line basis for the respective scan signal lines.

17. The liquid crystal display device as set forth in claim 14, wherein one of the data generating sections outputs the data signal without processing therein.

18. The liquid crystal display device as set forth in claim 14, wherein the data generating sections are switched over on the line-by-line basis for the respective scan signal lines.

19. The liquid crystal display device as set forth in claim 14, wherein

the data generating sections are switchable-over during display operation of the display section.

20. The liquid crystal display device as set forth in claim 15, wherein:

the data generating sections are switched over so that a difference between a target value and an overshoot value gradually becomes smaller as time elapsed after the liquid crystal display device is turned on.

21. The liquid crystal display device as set forth in claim 20, wherein:

the data generating sections are switched over in accordance with time elapsed after the liquid crystal display device is turned on.

22. The liquid crystal display device as set forth in claim 21, wherein the data generating section selecting section is a memory recording therein an address including address numbers indicating which scan signal line 6 the address is assigned for, and a series of number indicating the data generating section selected in accordance with how much time has elapsed since the power of the liquid crystal display device is turned on.

23. The liquid crystal display device as set forth in claim 14, wherein:

the data generating sections are switched over in accordance with temperature of the displaying section.

24. The liquid crystal display device as set forth in claim 23, wherein:

the data generating sections are switched over in accordance with temperature information obtained by a temperature sensor.

25. The liquid crystal display device as set forth in claim 23, wherein:

the data generating section selecting section includes a Look Up Table showing which one of the data generating sections is selected for a particular surrounding temperature.

26. The liquid crystal display device as set forth in claim 24, wherein:

the temperature sensor is provided on a thin film transistor substrate of the displaying section.

27. The liquid crystal display device as set forth in claim 26, wherein a plurality of the temperature sensors are provided in a direction perpendicular to a scan direction of the displaying area of the displaying section.

28. The liquid crystal display device as set forth in claim 26, wherein:

a temperature detection signal from the temperature sensor is transmitted via a spare line provided in the displaying section.

29. The liquid crystal display device as set forth in claim 27, wherein:

the data generating section selecting section includes a Look Up Table showing which one of the data generating sections is to be selected for various temperatures in the displaying section.

30. A driving device for driving the liquid crystal display device as set forth in claim 14.

31. A method for driving a liquid crystal display device including a plurality of scan signal lines, a plurality of data signal lines to which video signals are supplied as data signals, and a displaying section including pixels arranged in a matrix manner, the pixels respectively connected, via switching sections, with the scan signal lines and the data signal lines corresponding to intersecting points thereof, the method comprising the steps of:

(I) measuring temperature based on a detection signal transmitted from a temperature sensor to a periphery of the displaying section via a lead wire buried in the displaying section, the temperature sensor provided in at least one of the pixels in a displaying area of the displaying section; and

(II) driving the data signal lines by supplying the data signals to the data signal lines in accordance with the temperature of the pixels measured in the (I).

32. A method for driving a liquid crystal display device having, a plurality of scan signal lines, a plurality of data signal lines to which video signals are supplied as data signals appropriate for grey scale display, and a displaying section including pixels arranged in a matrix manner, the pixels respectively connected, via switching sections, with the scan signal lines and the data signal lines corresponding to intersecting points thereof, the method comprising the steps of:

(I) preparing a plurality of data generating sections for generating the data signals, and

(II) supplying the data signals to the pixels, the data signals generated in the one of the data generating sections selected on a line-by-line basis for the respective scan signal lines.

33. A method for driving a liquid crystal display device including, a plurality of scan signal lines, a plurality of data signal lines to which video signals are supplied as data signals appropriate for grey scale display, and a displaying section including pixels arranged in a matrix manner, the pixels respectively connected, via switching sections, with the scan signal lines and the data signal lines corresponding to intersecting points thereof, the method comprising the steps of:

(I) preparing a plurality of data generating sections for generating the data signals based on an inputted video signal and a video signal that is at least one frame earlier than the inputted video signal, and then generating, by using the plurality of the data generating sections, the data signals of the different output levels, based on difference between the video signal and the inputted video signal of the at least one frame earlier than the inputted video signal; and

(II) supplying the data signals to the pixels, the data signals generated in the one of the data generating sections selected on a line-by-line basis for the respective scan signal lines.

34. The method as set forth in claim 33, wherein a difference between the inputted video signal and a data signal outputted from a data generating section used for supplying the data signal to a lower area of the display section is greater than the difference between the inputted video signal and the data signals outputted from the data generating sections used for supplying the data signals to a top and a middle areas of the display section.