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

• US 9,600,109 B2
• Filed: 03/18/2011
• Issued: 03/21/2017
• 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): Glick, Edward
• Assistant Examiner(s): Quash, Anthony G
• Application Number:
  US13/051,000
• Publication Number:
  US 20110227851A1
• Time in Patent Office: 2,195 Days
• US Class Current: 1/1
• 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:

an array substrate including, a thin film transistor array, a common electrode, a pixel electrode, and a touch sensing unit;

a color filter substrate facing the array substrate;

an anti-static layer on an outer side of the color filter substrate and including an organic material and a carbon nano-tube dispersed in the organic material; and

a liquid crystal layer between the array substrate and the color filter substrate,

wherein the anti-static layer is an outermost layer such that a touch directly on the anti-static layer is detected by a capacitor, the capacitor comprising;

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

a dielectric layer including the anti-static layer, the color filter substrate, and the liquid crystal layer; and

the common electrode as a second electrode,

wherein the touch sensing unit further includes first to third regions, each of which includes a pixel region, and the common electrode has an island shape in each of the first to third regions,

wherein the second region is between and directly adjacent to the first region and the third region,

wherein an X direction sensing line extends through the first region and the third region, and connected by a connection line parallel to the X direction sensing line and extending completely through the second region,

wherein a Y direction sensing line extends only through the second region, and

wherein the X direction sensing line directly contacts the common electrode in the first and third regions, and the Y direction sensing line directly contacts the common electrode in the second region.

2. The device according to claim 1, wherein the anti-static layer has a sheet resistance of about 10⁶ to 10⁹ ohms per square (Ω

/sq).

3. The device according to claim 1, wherein the organic material includes polymethyl methacrylate (PMMA) or polyethylene terephthalate (PET).

4. The device according to claim 1, wherein the anti-static layer has a thickness of about 300 to 1000 angstroms.

5. The device according to claim 1, wherein the touch sensing unit includes:

the X direction sensing line;

the Y direction sensing line;

an X direction sensing circuit at one end of the X direction sensing line; and

a Y direction sensing circuit at one end of the Y direction sensing line,

wherein a change of capacitance by a touch is detected by the X direction sensing circuit and the Y direction sensing circuit through the X direction sensing line and the Y direction sensing line, respectively.

6. The device according to claim 1, wherein the X direction sensing line in the first region is electrically connected to the X direction sensing line in the third region.

7. The device according to claim 1, wherein the array substrate further includes:

gate lines;

an interlayer insulating layer on the gate lines;

data lines on the interlayer insulating layer and crossing the gate lines to define a plurality of pixel regions, wherein some of the plurality of pixel regions form each of the first to the third regions;

a plurality of thin film transistors in the transistor array, one in each pixel region and connected to one gate line and one data line;

a first passivation layer on the data lines and the thin film transistors, wherein the common electrode is on the first passivation layer and has an island shape in each of the first to third regions; and

a second passivation layer over the common electrode, wherein the first and the second passivation layers have a drain contact hole exposing a portion of the thin film transistor,

wherein the pixel electrode is on the second passivation layer and contacts the portion of the thin film transistor through the drain contact hole.

8. The device according to claim 7, wherein the pixel electrode has at least one opening to generate a fringe field with the common electrode.

9. The device according to claim 7, wherein the touch sensing unit includes:

the connection line in the second region under the interlayer insulating layer;

the X direction sensing line on the common electrode in the first and the third regions and overlapping a gate line in the first and the third regions;

the Y direction sensing line on the common electrode in the second region and overlapping a data line in the second region; and

first and second connection patterns on the second passivation layer,

wherein the second passivation layer has a first contact hole exposing an end of the X direction sensing line in the first region and a second contact hole exposing an end of the X direction sensing line in the third region, wherein the first and second passivation layers have a drain contact hole exposing a portion of the thin film transistor, and the first and second passivation layers and the interlayer insulating layer have third and fourth contact holes, respectively, exposing two ends of the connection line,

wherein a first end of the first connection pattern contacts the X direction sensing line in the first region through the first contact hole, and a second end of the first connection pattern contacts a first end of the connection line through the third contact hole, and

wherein a first end of the second connection pattern contacts the X direction sensing line in the third region through the second contact hole, and a second end of the second connection pattern contacts a second end of the connection line through the fourth contact hole.

10. The device according to claim 7, wherein the color filter substrate further includes:

a black matrix corresponding to boundaries of each pixel region; and

a color filter layer corresponding to each pixel region.

11. The device according to claim 1, wherein the pixel region is defined by an area where a gate line crosses a data line.