LIQUID CRYSTAL DISPLAY PANEL AND LIQUID CRYSTAL DISPLAY APPARATUS

• US 20100302227A1
• Filed: 04/21/2010
• Published: 12/02/2010
• Est. Priority Date: 05/29/2009
• Status: Active Grant

• Current Assignee: Casio Computer Company Limited
• Original Assignee: Casio Computer Company Limited
• Inventors: SASAKI, Kazuhiro, Iwasaki, Makoto, Nishino, Toshiharu
• Granted Patent: US 8,581,863 B2
• Time in Patent Office: Days
• US Class Current: 345/211
• CPC Class Codes: G02F 1/13338 Input devices, e.g. touch panels
• CPC Class Codes: G06F 3/0443 using a single layer of sensing electrodes
• CPC Class Codes: G06F 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes
• CPC Class Codes: G06F 3/0447 Position sensing using the local deformation of sensor cells

Abstract

A liquid crystal display panel in which coordinate detection electrodes are formed on a first substrate and protruding contact portions are formed on a second substrate as a touch panel function includes a conversion circuit formed therein. The conversion circuit subjects information indicative of whether the protruding contact portions are in contact with the coordinate detection electrodes to parallel/serial conversion to output the converted information to the coordinate detection circuit.

Claims

1. A liquid crystal display panel in which pixel electrodes connected with pixel transistors are arranged to face an opposed electrode through a liquid crystal layer per each pixel and an alignment direction of liquid crystal molecules in the liquid crystal layer changes by controlling a voltage between the pixel electrodes and the opposed electrode, comprising:

scanning lines which extend in parallel to each other and through which ON signals for turning on respective corresponding pixel transistors during a predetermined period are supplied to the respective corresponding pixel transistors;

first coordinate detection electrodes which are arranged in a predetermined direction and some of which correspond to the scanning lines different from each other; and

first coordinate detection transistors which electrically connect the first coordinate detection electrodes corresponding to the scanning lines to a first output line commonly connected with the first coordinate detection transistors based on the ON signals supplied to the pixel transistors from the scanning lines.

2. The liquid crystal display panel according to claim 1, wherein the pixel transistors, the first coordinate detection transistors, and the first output line are formed on the same substrate.

3. The liquid crystal display panel according to claim 1, second coordinate detection electrodes which are arranged along parallel lines perpendicular to the predetermined direction and some of which correspond to the scanning lines different from each other;

and

second coordinate detection transistors which electrically connect the second coordinate detection electrodes corresponding to the scanning lines to a second output line commonly connected with the second coordinate detection transistors based on the ON signals supplied to the pixel transistors from the scanning lines.

4. The liquid crystal display panel according to claim 3, wherein the pixel transistors, the second coordinate detection transistors, and the second output line are formed on the same substrate.

5. The liquid crystal display panel according to claim 1, comprising:

a first substrate on which the first coordinate detection electrodes are formed; and

a second substrate which is arranged to face the first substrate and on which the opposed electrode is formed,

the second substrate including protruding contact portions which come into contact with the first coordinate detection electrodes when the second substrate undergoes flexural deformation due to pressing.

6. A liquid crystal display panel in which pixel electrodes connected with pixel transistors are arranged to face an opposed electrode through a liquid crystal layer per each pixel and an alignment direction of liquid crystal molecules in the liquid crystal layer changes by controlling a voltage between the pixel electrodes and the opposed electrode, comprising:

scanning lines which extend in parallel to each other and through which ON signals for turning on respective corresponding pixel transistors during a predetermined period are supplied to the respective corresponding pixel transistors;

first coordinate detection lines which extend in parallel to each other and correspond to the scanning lines different from each other; and

first coordinate detection transistors which electrically connect the first coordinate detection lines corresponding to the scanning lines to a first output line commonly connected with the first coordinate detection transistors based on the ON signals supplied to the pixel transistors from the scanning lines.

7. The liquid crystal display panel according to claim 6, wherein the pixel transistors, the first coordinate detection lines, the first coordinate detection transistors, and the first output line are formed on the same substrate.

8. The liquid crystal display panel according to claim 6, wherein each of the first coordinate detection lines is connected with first coordinate detection electrodes.

9. The liquid crystal display panel according to claim 8, comprising:

a first substrate on which the first coordinate detection electrodes are formed; and

a second substrate which is arranged to face the first substrate and on which the opposed electrode is formed,

the second substrate including protruding contact portions which come into contact with the first coordinate detection electrodes when the second substrate undergoes flexural deformation due to pressing.

10. The liquid crystal display panel according to claim 6, wherein the first coordinate detection lines extend in a direction parallel or perpendicular to the scanning lines.

11. The liquid crystal display panel according to claim 6, comprising:

second coordinate detection lines which extend in a direction perpendicular to a direction in which the first coordinate detection lines extend and which correspond to the scanning lines different from each other; and

second coordinate detection transistors which electrically connect the second coordinate detection lines corresponding to the scanning lines to a second output line commonly connected with the second coordinate detection transistors based on the ON signals supplied to the pixel transistors from the scanning lines.

12. The liquid crystal display panel according to claim 11, wherein each of the first coordinate detection lines is connected with first coordinate detection electrodes, and

each of the second coordinate detection lines is connected with second coordinate detection electrodes.

13. The liquid crystal display panel according to claim 12, comprising:

a first substrate on which the first coordinate detection electrodes and the second coordinate detection electrodes are formed; and

a second substrate which is arranged to face the first substrate and on which the opposed electrode is formed,

the second substrate including protruding contact portions which come into contact with both the first coordinate detection electrodes and the second coordinate detection electrodes when the second substrate undergoes flexural deformation due to pressing.

14. A liquid crystal display apparatus in which pixel electrodes connected with pixel transistors are arranged to face an opposed electrode through a liquid crystal layer per each pixel and an alignment direction of liquid crystal molecules in the liquid crystal layer is controlled by controlling a voltage applied to a space between the pixel electrodes and the opposed electrode, comprising:

a scan driver which sequentially outputs ON signals for turning on the pixel transistors during a predetermined period to scanning lines extending in parallel to each other;

first coordinate detection electrodes which are arranged in a predetermined direction and some of which correspond to the scanning lines different from each other; and

first coordinate detection transistors which electrically connect the first coordinate detection electrodes corresponding to the scanning lines to a first output line commonly connected with the first coordinate detection transistors based on the ON signals output to the scanning lines,

the pixel transistors, the first coordinate detection transistors, and the first output line being formed on the same substrate.

15. The apparatus according to claim 14, comprising:

second coordinate detection electrodes which are arranged along parallel lines perpendicular to the predetermined direction and some of which correspond to the scanning lines different from each other; and

second coordinate detection transistors which electrically connect the second coordinate detection electrodes corresponding to the scanning lines to the second output line commonly connected with the second coordinate detection transistors based on the ON signals supplied to the pixel transistors from the scanning lines,

the pixel transistors, the second coordinate detection transistors, and the second output line being formed on the same substrate.

16. The apparatus according to claim 14, comprising a coordinate detection circuit which causes the first coordinate detection electrodes and the second coordinate detection electrodes to hold a reset voltage different from a voltage of the opposed electrode in synchronization with an output timing of the ON signals output from the scan driver.

17. The apparatus according to claim 14, comprising a coordinate detection circuit which detects a contact position on the substrate having the opposed electrode with respect to the substrate having the first coordinate detection electrodes based on voltage information in the first coordinate detection electrodes detected through the first output line.

18. The liquid crystal display panel according to claim 14, comprising:

a first substrate on which the first coordinate detection electrodes are formed; and

a second substrate which is arranged to face the first substrate and on which the opposed electrode is formed,

the second substrate including protruding contact portions which come into contact with the first coordinate detection electrodes when the second substrate undergoes flexural deformation due to pressing.

19. The apparatus according to claim 18, comprising a coordinate detection circuit which detects the first coordinate detection electrode that has come into contact with the protruding contact portion based on voltage information in the first coordinate detection electrodes detected through the first output line.

20. A liquid crystal display apparatus in which pixel electrodes connected with pixel transistors are arranged to face an opposed electrode through a liquid crystal layer per each pixel and an alignment direction of liquid crystal molecules in the liquid crystal layer is controlled by controlling a voltage applied to a space between the pixel electrodes and the opposed electrode, comprising:

a scan driver which sequentially outputs ON signals for turning on the pixel transistors during a predetermined period to scanning lines extending in parallel to each other;

first coordinate detection lines which extend to be perpendicular to the scanning lines and correspond to the scanning lines different from each other;

second coordinate detection lines which extend in parallel to the scanning lines and correspond to the scanning lines different from each other;

first coordinate detection transistors which electrically connect the first coordinate detection lines corresponding to the scanning lines to a first output line commonly connected with the first coordinate detection transistors based on the ON signals supplied to the pixel transistors from the scanning lines; and

second coordinate detection transistors which electrically connect the second coordinate detection lines corresponding to the scanning lines to a second output line commonly connected with the second coordinate detection transistors based on the ON signals supplied to the pixel transistors from the scanning lines,

the pixel transistors, the first coordinate detection lines, the second coordinate detection lines, the first coordinate detection transistors, the second coordinate detection transistors, the first output line, and the second output line being formed on the same substrate.

21. The apparatus according to claim 20, wherein the number of the first coordinate detection lines and the number of the second coordinate detection lines are equal to the number of the scanning lines.

22. A liquid crystal display apparatus comprising:

a liquid crystal display panel in which a liquid crystal layer is formed between a first substrate having pixel transistors and pixel electrodes and a second substrate having an opposed electrode and protruding contact portions formed on the second substrate come into contact with coordinate detection electrodes formed on the first substrate when the liquid crystal display panel is pressed;

a coordinate detection circuit which acquires contact information between the protruding contact portions and the coordinate detection electrodes; and

a scan driver which outputs ON signals for turning on the pixel transistors during a predetermined period to the pixel transistors through scanning lines formed on the first substrate,

in the liquid crystal display panel, coordinate detection lines corresponding to scanning lines different from each other and corresponding to the coordinate detection electrodes different from each other and coordinate detection transistors which electrically connect the coordinate detection lines corresponding to the scanning lines to an output line commonly connected with the coordinate detection transistors based on the ON signals output to the scanning lines from the scan driver being formed on the first substrate.

23. The apparatus according to claim 22, wherein the coordinate detection circuit is provided separately from the liquid crystal display panel and acquires the contact information through the output line.

24. The apparatus according to claim 22, wherein the first substrate and the second substrate are bonded to each other so as to prevent the protruding contact portions from coming into contact with the coordinate detection electrodes when the liquid crystal display panel is not pressed.

25. A liquid crystal display apparatus comprising:

a liquid crystal display panel in which coordinate detection electrodes are formed on a first substrate and protruding contact portions are formed on a second substrate as a touch panel function; and

a coordinate detection circuit which detects a coordinate position at which the liquid crystal display panel is pressed,

the liquid crystal display panel including a conversion circuit which subjects information indicative of whether the protruding contact portions are in contact with the coordinate detection electrodes to parallel/serial conversion to output the converted information to the coordinate detection circuit.

26. The apparatus according to claim 25, wherein two systems of the conversion circuit are formed corresponding to two coordinate axes different from each other.

27. The apparatus according to claim 25, comprising a scan driver which outputs a gate signal to the scanning lines formed in the liquid crystal display panel, the conversion circuit operating based on the gate signal.