Conductive sheet, capacitive touch panel, and display device

• US 10,254,904 B2
• Filed: 05/27/2016
• Issued: 04/09/2019
• Est. Priority Date: 12/03/2013
• Status: Active Grant

• Current Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Original Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Inventors: Satou, Tasuku
• Primary Examiner(s): Davis, Tony
• Application Number:
  US15/167,418
• Publication Number:
  US 20160274703A1
• Time in Patent Office: 1,047 Days
• Field of Search: 345633, 345170-173
• CPC Class Codes: G06F 2203/04112 Electrode mesh in capacitive digitiser: electrode for touch sensing is formed of a mesh of very fine, normally metallic, interconnected lines that are almost invisible to see. This provides a quite large but transparent electrode surface, without need for ITO or similar transparent conductive material
• 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

Abstract

In a conductive sheet constituting a touch panel for use in a display device, it is possible to improve the transmittance of electrodes having meshes, to improve sensitivity of touch detection, and to suppress the occurrence of moire. A conductive sheet has an underlying first electrode and an overlying second electrode with a second sheet body as an insulating layer sandwiched therebetween. The first electrode and the second electrode respectively include a plurality of first cells and a plurality of second cells which are formed in a diamond shape by making thin wires and formed with metal wires intersect each other. The average cell pitch of the second cells is set to an integer multiple equal to or greater than two times and equal to or less than eight times the average cell pitch of the first cell.

Claims

1. A conductive sheet comprising:

a first electrode disposed under an insulating layer; and

a second electrode disposed above the insulating layer, the first electrode and the second electrode being opposed to each other through the insulating layer,

wherein the first electrode has a first mesh with a plurality of linked first cells in a diamond shape formed by making metal wires intersecting each other, a plurality of first electrodes extending in a first direction and being arranged in parallel to a second direction orthogonal to the first direction,

the second electrode has a second mesh with a plurality of linked second cells in a diamond shape formed by making metal wires intersecting each other, a plurality of second electrodes extending in the second direction and being arranged in parallel to the first direction,

when the average cell pitch of the first cells is Pd and the average cell pitch of the second cells is Ps, Ps/Pd is an integer equal to or greater than 2 and equal to or less than 8,

the first electrode has in-opening cells that the first cells are provided in the openings of the second cells in plan view,

density of the metal wires is the same in plan view in an overlapping portion where the first electrode overlaps the second electrode, and

the first cells have two obtuse angles and two acute angles, intersection angles of the obtuse angles in a diagonal relationship being the same angle greater than 90°

, and intersection angles of the acute angles being the same angle less than 90°

.

2. The conductive sheet according to claim 1,

wherein Ps/Pd is an integer equal to or greater than 2 and equal to or less than 6.

3. The conductive sheet according to claim 1,

wherein an effective electrode area of the second electrode is equal to or greater than 70% of an effective touch area.

4. The conductive sheet according to claim 2,

wherein an effective electrode area of the second electrode is equal to or greater than 70% of an effective touch area.

5. The conductive sheet according to claim 1,

wherein dummy thin wires are provided in the openings of the second cells at positions where the first cells are included in the openings of the second cells in plan view.

6. The conductive sheet according to claim 2,

wherein dummy thin wires are provided in the openings of the second cells at positions where the first cells are included in the openings of the second cells in plan view.

7. The conductive sheet according to claim 3,

wherein dummy thin wires are provided in the openings of the second cells at positions where the first cells are included in the openings of the second cells in plan view.

8. The conductive sheet according to claim 1,

wherein the average cell pitch of the first cells in the openings is set to be smaller than the average cell pitch of the cells surrounding the first cells in the openings at positions where the first cells are included in the openings of the second cells in plan view.

9. The conductive sheet according to claim 2,

wherein the average cell pitch of the first cells in the openings is set to be smaller than the average cell pitch of the cells surrounding the first cells in the openings at positions where the first cells are included in the openings of the second cells in plan view.

10. The conductive sheet according to claim 1,

wherein, when the electrode width of the first electrode is Wd and the electrode width of the second electrode is Ws, Ws/Wd is equal to or greater than 0.5 and equal to or less than 1.5.

11. The conductive sheet according to claim 2,

wherein, when the electrode width of the first electrode is Wd and the electrode width of the second electrode is Ws, Ws/Wd is equal to or greater than 0.5 and equal to or less than 1.5.

12. The conductive sheet according claim 1,

wherein the average cell pitch of the first cells positioned in the openings of the second cells is equal to or greater than 50 μ

m and equal to or less than 400 μ

m, and the average cell pitch of the second cells is equal to or greater than 100 μ

m and equal to or less than 3,200 μ

m.

13. The conductive sheet according claim 2,

wherein the average cell pitch of the first cells positioned in the openings of the second cells is equal to or greater than 50 μ

m and equal to or less than 400 μ

m, and the average cell pitch of the second cells is equal to or greater than 100 μ

m and equal to or less than 3,200 μ

m.

14. The conductive sheet according to claim 1,

wherein at least the metal wires forming the first cells or the metal wires forming the second cells are reduced in line width or become a disconnection portion at a part of places where the first mesh and the second mesh are opposed to each other.

15. The conductive sheet according to claim 2,

wherein at least the metal wires forming the first cells or the metal wires forming the second cells are reduced in line width or become a disconnection portion at a part of places where the first mesh and the second mesh are opposed to each other.

16. The conductive sheet according to claim 1,

wherein the electrode width of at least the first electrode or the second electrode is set to be smaller than other parts at places where the first mesh and the second mesh are opposed to each other.

17. The conductive sheet according to claim 2,

wherein the electrode width of at least the first electrode or the second electrode is set to be smaller than other parts at places where the first mesh and the second mesh are opposed to each other.

18. A capacitive touch panel comprising:

the conductive sheet according to claim 1.

19. A capacitive touch panel comprising:

the conductive sheet according to claim 2.

20. A display device comprising:

the capacitive touch panel according to claim 18.

21. The conductive sheet according to claim 1,

wherein the metal wires are provided in the in-opening cells and eight first cells surrounding the respective in-opening cells in plan view, and

density of the metal wires is the same in plan view in the in-opening cells and the eight first cells surrounding the respective in-opening cells in plan view.

22. The conductive sheet according to claim 1,

wherein the intersection angles of the acute angles are the same angle less than 70°

.