Liquid crystal display device

• US 10,452,221 B2
• Filed: 11/13/2017
• Issued: 10/22/2019
• Est. Priority Date: 05/13/2015
• Status: Active Grant

• Current Assignee: Toppan Printing Co., Ltd. (TOPPAN Holdings, Inc.)
• Original Assignee: Toppan Printing Co., Ltd. (TOPPAN Holdings, Inc.)
• Inventors: Kimura, Yukihiro, Fukuyoshi, Kenzo
• Primary Examiner(s): Edwards, Mark
• Application Number:
  US15/810,914
• Publication Number:
  US 20180067592A1
• Time in Patent Office: 708 Days
• CPC Class Codes: G02F 1/1343 Electrodes reflective electrodes G02F1/133553
• CPC Class Codes: G02F 1/1368 in which the switching element is a three-electrode device G02F1/136277 takes precedence
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/04166 Details of scanning methods, e.g. sampling time, grouping of sub areas or time sharing with display driving Synchronisation with the driving of the display or the backlighting unit to avoid interferences generated internally G06F3/04184
• 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

Abstract

A liquid crystal display device includes a display device substrate including a first touch sensing wiring, an array substrate including a second touch sensing wiring orthogonally intersecting the first touch sensing wiring, a liquid crystal layer disposed between the display device substrate and the array substrate, a controller that supplies a positive first image signal to the first source wiring, supplies a negative second image to the second source wiring, applies a liquid crystal display voltage between the pixel electrode and the common electrode being synchronized to supply of the first image signal and the second image signal, thereby driving the liquid crystal layer, performing an image display, and applying a voltage to the second touch sensing wiring after performing the image display.

Claims

1. A liquid crystal display device, comprising:

a display device substrate including a first touch sensing wiring;

an array substrate including an insulation layer structure including a first insulation layer and a second insulation layer foil led on one another, a pixel electrode positioned in each of pixel openings formed in the insulation layer structure and having a polygonal shape, a common electrode formed between the first and second insulation layers, a wiring structure including a first gate wiring, a second gate wiring, a first source wiring and a second source wiring such that the first gate and source wirings orthogonally intersect with one another and the second gate and source wirings orthogonally intersect with one another in a plan view, and a second touch sensing wiring orthogonally intersecting the first touch sensing wiring in the plan view, the second touch sensing wiring being formed on the first insulation layer, between the first and second insulation layers, or on the second insulation layer away from the first insulation layer;

a liquid crystal layer formed between the display device substrate and the array substrate; and

a controller configured to supply a positive first image signal to the first source wiring, supply a negative second image signal to the second source wiring, apply a liquid crystal drive voltage between the pixel electrode and the common electrode being synchronized to the first image signal and the second image signal supplied to the first source wiring and the second source wiring respectively, thereby driving the liquid crystal layer, performing an image display, and applying a voltage to the second touch sensing wiring after performing the image display.

2. The liquid crystal display device of claim 1, wherein the first and second gate wirings and the first and second source wirings define the pixel openings in the plan view.

3. The liquid crystal display device of claim 1, wherein the first and second source wirings are formed such that longitudinal sides of the pixel openings extend along the first and second source wirings.

4. The liquid crystal display device of claim 1, wherein one of the first and second touch sensing wirings overlaps with the first and second gate wirings in the plan view, and the other of the first and second touch sensing wirings overlaps with the first and second source wirings in the plan view.

5. The liquid crystal display device of claim 1, wherein the second touch sensing wiring is formed on the first insulation layer, between the first and second insulation layers, or on the second insulation layer away from the first insulation layer, such that the second touch sensing wiring is positioned at a greater distance from a display surface of the display device substrate than a distance of the first touch sensing wiring from the display surface, in a cross-sectional view.

6. The liquid crystal display device of claim 1, wherein the first and second gate wirings are parallel to each other and located between two adjacent ones of the pixel openings.

7. The liquid crystal display device of claim 1, further comprising:

a backlight unit formed on a back surface or a side surface of the array substrate and configured such that emission of the backlight unit is stopped when the voltage is applied to the second touch sensing wiring.

8. The liquid crystal display device of claim 1, wherein the controller is configured to drive the liquid crystal layer by a fringe electric field produced between the pixel electrode and the common electrode.

9. The liquid crystal display device of claim 8, wherein the display device substrate includes a transparent electrode, and the liquid crystal layer is driven by the fringe electric field and an electric field in a thickness direction of the liquid crystal layer produced between the pixel electrode and the transparent electrode.

10. The liquid crystal display device of claim 1, wherein the common electrode includes a portion overlapping with the pixel electrode, and a protrusion protruding from an end portion of the pixel electrode.

11. The liquid crystal display device of claim 1, wherein the controller is configured to apply the voltage to the second touch sensing wiring after the liquid crystal drive voltage is applied to the pixel electrode and when the liquid crystal drive voltage is not applied to the pixel electrode.

13. The liquid crystal display device of claim 1, wherein each of the first and second touch sensing wirings includes a metal layer.

14. The liquid crystal display device of claim 13, wherein the display device substrate includes a first transparent substrate, and the first touch sensing wiring has a two layer structure including a black layer foil led over the first transparent substrate, and the metal layer formed on the black layer.

15. The liquid crystal display device of claim 13, wherein the array substrate includes a second transparent substrate, the second touch sensing wiring includes a black layer formed over the second transparent substrate, and a two layer structure in which the metal layer is laminated on the black layer.

16. The liquid crystal display device of claim 13, wherein the metal layer includes a copper containing layer formed between conductive metal oxide layers.

17. The liquid crystal display device of claim 16, wherein each of the conductive metal oxide layers comprises a composite oxide containing zinc oxide, indium oxide, and tin oxide.

18. The liquid crystal display device of claim 13, further comprising:

first and second active elements electrically connected to the pixel electrode,

wherein the first and second active elements are thin film transistors each having a channel layer comprising a semiconductor, and the metal layer of the second touch sensing wiring has a portion forming a light shielding layer that covers the channel layer in a plan view.

19. The liquid crystal display device of claim 18, wherein the channel layer comprises an oxide semiconductor.

20. The liquid crystal display device of claim 1, wherein the display device substrate has at least one of a red filter, a green filter and a blue filter at each of positions corresponding to the pixel openings.

21. The liquid crystal display device of claim 20, further comprising:

a black matrix layer formed on the display device substrate such that the black matrix layer defines the pixel openings.

12. A liquid crystal display device, comprising:

a display device substrate including a first touch sensing wiring;

an array substrate including an insulation layer structure including a first insulation layer and a second insulation layer formed on one another, a pixel electrode positioned in each of pixel openings formed in the insulation layer structure and having a polygonal shape, a common electrode formed between the first and second insulation layers, a wiring structure including a first gate wiring, a second gate wiring, a first source wiring and a second source wiring such that the first gate and source wirings orthogonally intersect with one another and the second gate and source wirings orthogonally intersect with one another in a plan view, and a second touch sensing wiring orthogonally intersecting the first touch sensing wiring in the plan view;

a liquid crystal layer formed between the display device substrate and the array substrate; and

a controller configured to supply a positive first image signal to the first source wiring, supply a negative second image signal to the second source wiring, apply a liquid crystal drive voltage between the pixel electrode and the common electrode being synchronized to the first image signal and the second image signal supplied to the first source wiring and the second source wiring respectively, thereby driving the liquid crystal layer, performing an image display, and applying a voltage to the second touch sensing wiring after performing the image display,

wherein the controller is configured such that the voltage applied to the second touch wiring includes a positive voltage and a negative voltage, and that the voltage is inverted to positive or negative for each fixed period of an image display.

22. A liquid crystal display device, comprising:

a display device substrate including a first touch sensing wiring;

an array substrate including an insulation layer structure including a first insulation layer and a second insulation layer formed on one another, a pixel electrode positioned in each of pixel openings formed in the insulation layer structure and having a polygonal shape, a common electrode formed between the first and second insulation layers, a wiring structure including a first gate wiring, a second gate wiring, a first source wiring and a second source wiring such that the first gate and source wirings orthogonally intersect with one another and the second gate and source wirings orthogonally intersect with one another in a plan view, and a second touch sensing wiring orthogonally intersecting the first touch sensing wiring in a plan view, the second touch sensing wiring being formed on the first insulation layer, between the first and second insulation layers, or on the second insulation layer away from the first insulation layer;

a liquid crystal layer formed between the display device substrate and the array substrate; and

a controller configured to supply a positive first image signal to the first source wiring, supply a negative second image signal to the second source wiring, apply a liquid crystal drive voltage between the pixel electrode and the common electrode being synchronized to the first image signal and the second image signal supplied to the first source wiring and the second source wiring respectively, thereby driving the liquid crystal layer, and performing a touch sensing driving by the first touch sensing wiring and the second touch sensing wiring, during at least one of a stable period of an image display and a stable period of a black display after displaying an image.

23. The liquid crystal display device of claim 22, wherein the controller is configured to apply a touch sensing drive voltage to one of the first and second touch sensing wirings, and detect a touch sensing signal via the other of the first and second touch sensing wirings, when performing the touch sensing driving.

24. The liquid crystal display device according to claim 23, wherein the touch sensing drive voltage is applied to the second touch sensing wiring, and the first touch sensing wiring detects the touch sensing signal.

25. The liquid crystal display device according to claim 22, further comprising:

a backlight unit formed on a back surface or a side surface of the array substrate,

wherein emission of the backlight unit is stopped in the black display stable period.

26. The liquid crystal display device according to claim 22, wherein the display device substrate has at least one of a red filter, a green filter and a blue filter at each of positions corresponding to the pixel openings.

27. The liquid crystal display device according to claim 26, further comprising:

a black matrix layer formed on the display device substrate such that the black matrix layer defines the pixel openings.