Touch sensing type liquid crystal display device and method of fabricating the same

• US 10,620,729 B2
• Filed: 06/30/2017
• Issued: 04/14/2020
• Est. Priority Date: 03/19/2010
• Status: Active Grant

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Display Co., Ltd.
• Inventors: Oh, Kum-Mi, Kim, Jin-Wuk, Kim, Sung-Hee
• Primary Examiner(s): Duong, Thoi V
• Application Number:
  US15/640,008
• Publication Number:
  US 20170300156A1
• Time in Patent Office: 1,019 Days
• CPC Class Codes: G02F 1/133345 Insulating layers G02F1/1335, G02F1/1337, G02F1/135, G02F1/136 take precedence
• CPC Class Codes: G02F 1/13338 Input devices, e.g. touch panels
• CPC Class Codes: G02F 1/133512 Light shielding layers, e.g. black matrix G02F1/136209 takes precedence
• CPC Class Codes: G02F 1/133514 Colour filters
• CPC Class Codes: G02F 1/134309 characterised by their geometrical arrangement
• CPC Class Codes: G02F 1/134318 having a patterned common electrode
• CPC Class Codes: G02F 1/134363 for applying an electric field parallel to the substrate, i.e. in-plane switching [IPS]
• CPC Class Codes: G02F 1/134372 for fringe field switching [FFS] where the common electrode is not patterned
• CPC Class Codes: G02F 1/136204 Arrangements to prevent high voltage or static electricity failures
• CPC Class Codes: G02F 1/136295 Materials; Compositions; Manufacture processes
• CPC Class Codes: G02F 1/1368 in which the switching element is a three-electrode device G02F1/136277 takes precedence
• CPC Class Codes: G02F 2201/121 common or background
• CPC Class Codes: G02F 2201/123 pixel
• CPC Class Codes: G02F 2202/22 Antistatic materials or arrangements
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/0445 using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer
• 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 3/047 using sets of wires, e.g. crossed wires
• CPC Class Codes: H01L 27/124 with a particular composition, shape or layout of the wiring layers specially adapted to the circuit arrangement, e.g. scanning lines in LCD pixel circuits wiring structures per se H01L23/52

Abstract

A touch sensing type liquid crystal display device includes an array substrate includes a first substrate, a common electrode, a pixel electrode, and a touch sensing unit; a color filter substrate including a second substrate and facing the array substrate; an anti-static layer on an outer side of the second substrate and including an organic material and a carbon nano-tube; and a liquid crystal layer between the first substrate and an inner side of the second substrate.

Claims

1. A touch sensing type liquid crystal display device, comprising:

first and second substrates facing each other;

a liquid crystal layer between the first and second substrates; and

an anti-static layer on an outer side of the second substrate,

wherein the first substrate includes;

a plurality of first signal lines;

a plurality of second signal lines crossing the plurality of first signal lines;

a plurality of pixel electrodes;

a plurality of common electrodes;

a sensing line electrically connected to at least one common electrode of the plurality of common electrodes and extending along at least one of the plurality of first signal lines; and

a sensing circuit electrically connected to the sensing line, and

wherein the sensing circuit detects a change of capacitance between an object and the at least one common electrode of the plurality of common electrodes through the sensing line for sensing a touched position.

2. The touch sensing type liquid crystal display device according to claim 1, wherein the plurality of common electrodes include a plurality of first common electrodes and a plurality of second common electrodes,

wherein the sensing line electrically connects to the plurality of first common electrodes, and

wherein the liquid crystal layer is driven by an electric field between the plurality of pixel electrodes and the plurality of first common electrodes.

3. The touch sensing type liquid crystal display device according to claim 2, wherein the plurality of first common electrodes group into a first touch block defining a unit region for touch sensing, and the first touch block overlaps with the sensing line.

4. The touch sensing type liquid crystal display device according to claim 3, wherein the first touch block is separated from the second touch block.

5. The touch sensing type liquid crystal display device according to claim 2, wherein the plurality of second common electrodes group into a second touch block defining a unit region for touch sensing.

6. The touch sensing type liquid crystal display device according to claim 2, wherein the plurality of first common electrodes are separated from the plurality of second common electrodes.

7. The touch sensing type liquid crystal display device according to claim 2, wherein the first touch block includes a plurality of pixel regions.

8. The touch sensing type liquid crystal display device according to claim 2, wherein a touch on the anti-static layer is detected by a capacitor, and the capacitor includes:

the object touching the anti-static layer as a first electrode;

a dielectric layer including at least one of the anti-static layer, the second substrate, and the liquid crystal layer; and

the first common electrode as a second electrode.

9. The touch sensing type liquid crystal display device according to claim 2, wherein the plurality of first common electrodes in the region arranged along the at least one of the plurality of first signal lines are electrically connected by the sensing line.

10. The touch sensing type liquid crystal display device according to claim 1, wherein the anti-static layer serves as a path for a static electricity and serves as a dielectric layer for sensing the touch position.

11. The touch sensing type liquid crystal display device according to claim 1, wherein the sensing line overlaps the second signal lines or is parallel to one of the first signal lines.

12. The touch sensing type liquid crystal display device according to claim 1, wherein the anti-static layer has a sheet resistance of about 10⁶ to 10⁹ ohms per square (Ω

/sq).

13. The touch sensing type liquid crystal display device according to claim 1, wherein a minimum distance between the plurality of pixel electrodes and the plurality of common electrodes is less than a minimum distance between the anti-static layer and the plurality of common electrodes.

14. The touch sensing type liquid crystal display device according to claim 1, wherein a thickness of one of the first and second substrates is greater than a thickness of the anti-static layer.

15. The touch sensing type liquid crystal display device according to claim 1, wherein one of the plurality of pixel electrodes and the plurality of common electrodes has at least one opening and the other one has a plate shape to generate an electric field between the pixel electrodes and the plurality of common electrodes.

16. The touch sensing type liquid crystal display device according to claim 1, wherein the first substrate further includes an insulation layer between the plurality of pixel electrodes and the plurality of common electrodes forming a storage capacitor.

17. The touch sensing type liquid crystal display device according to claim 1, wherein the anti-static layer includes a carbon nanotube material.

18. A touch sensing type display device, comprising:

a display panel including first and second substrates facing each other, a plurality of signal lines, a plurality of pixel electrodes, a plurality of common electrodes, a sensing line electrically connected to at least one common electrode of the plurality of common electrodes, and a sensing circuit electrically connected to the sensing line; and

an anti-static layer on an outer side of the second substrate,

wherein the sensing line extends along at least one of the plurality of signal lines, and

wherein the sensing circuit detects a change of capacitance between an object and the at least one common electrode of the plurality of common electrodes through the sensing line for sensing a touched position.

19. The touch sensing type display device according to claim 18, wherein the plurality of common electrodes include a plurality of first common electrodes and a plurality of second common electrodes, and

wherein the display panel is driven by an electric field between the plurality of pixel electrodes and the plurality of first common electrodes.

20. The touch sensing type display device according to claim 19, wherein the plurality of first common electrodes group into a first touch block defining a unit region for touch sensing, and the first touch block overlaps with the sensing line.

21. The touch sensing type display device according to claim 20, wherein the first touch block includes a plurality of pixel regions.

22. The touch sensing type display device according to claim 19, wherein the plurality of second common electrodes group into a second touch block defining a unit region for the touch sensing.

23. The touch sensing type display device according to claim 22, wherein the first touch block is separated from the second touch block.

24. The touch sensing type display device according to claim 19, wherein the plurality of first common electrodes are separated from the plurality of second common electrodes.

25. The touch sensing type display device according to claim 18, wherein the anti-static layer serves as a conductive path for static electricity and serves as an insulating layer for sensing a touch position.

26. The touch sensing type display device according to claim 18, wherein the display panel further includes:

a liquid crystal layer between the first and second substrates,

wherein the plurality of signal lines, the plurality of pixel electrodes, the plurality of common electrodes, the sensing line, and the sensing circuit are disposed on the first substrate.

27. The touch sensing type display device according to claim 26, wherein a touch on the anti-static layer is detected by a capacitor, and the capacitor includes:

the object touching the anti-static layer as a first electrode;

a dielectric layer including at least one of the anti-static layer, the second substrate, and the liquid crystal layer; and

the first common electrode as a second electrode.

28. The touch sensing type display device according to claim 18, wherein the plurality of signal lines include a plurality of first signal lines and a plurality of second signal lines intersecting the plurality of first signal lines, and

wherein the sensing line overlaps at least one of the plurality of second signal lines and is parallel to one of the first signal lines.

29. The touch sensing type display device according to claim 28, wherein the plurality of first common electrodes arranged along the at least one of the plurality of first signal lines are electrically connected with the sensing line.