Touch panel and display device with the same

• US 10,620,733 B2
• Filed: 09/10/2018
• Issued: 04/14/2020
• Est. Priority Date: 03/10/2016
• Status: Active Grant

• Current Assignee: Paneltouch Technologies LLC (Touch Display LLC)
• Original Assignee: Panasonic Liquid Crystal Display Company Limited (Panasonic Holdings Corporation)
• Inventors: Koudo, Toshikazu, Shiiba, Ken
• Primary Examiner(s): Karimi, Pegeman
• Application Number:
  US16/126,687
• Publication Number:
  US 20190004657A1
• Time in Patent Office: 582 Days
• 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 3/04164 Connections between sensors and controllers, e.g. routing lines between electrodes and connection pads
• 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 3/0448 Details of the electrode shape, e.g. for enhancing the detection of touches, for generating specific electric field shapes, for enhancing display quality
• CPC Class Codes: G06F 3/047 using sets of wires, e.g. crossed wires

Abstract

A touch panel comprising first electrodes that extend in a first direction and second electrodes that extend in the second direction, wherein each of the first electrodes and each of the second electrodes are constructed with conductive wires having mesh shape, each of the first electrodes is formed such that wide portions and narrow portions, each of the narrow portions having a width that is a length in the second direction narrower than each of the wide portions, are alternately arranged in the first direction, and one wide portion and one narrow portion in an endmost first electrode formed at an end are narrower than one wide portion and one narrow portion in an inner first electrode located inside the endmost first electrode, respectively.

Claims

1. A touch panel comprising:

a plurality of first electrodes that extend in a first direction and are arrayed in a second direction intersecting the first direction;

a plurality of second electrodes that extend in the second direction and are arrayed in the first direction; and

an insulating film disposed between the plurality of first electrodes and the plurality of second electrodes,

wherein each of the plurality of first electrodes and each of the plurality of the second electrodes are constructed with a plurality of conductive wires, the plurality of conductive wires having mesh shape,

each of the plurality of first electrodes is formed having a plurality of wide portions and a plurality of narrow portions, each of the plurality of narrow portions of the plurality of first electrodes has a width that is a length in the second direction narrower than each of the plurality of wide portions, which are alternately arranged in the first direction,

one wide portion from the plurality of wide portions and one narrow portion from the plurality of narrow portions in an endmost first electrode formed at an end among the plurality of first electrodes are narrower than one wide portion from the plurality of wide portions and one narrow portion from the plurality of narrow portions in an inner first electrode located inside the endmost first electrode, respectively,

each of the plurality of second electrodes is formed having a plurality of wide portions and a plurality of narrow portions, each of the plurality of narrow portions of the plurality of second electrodes has a width that is a length in the first direction narrower than each of the plurality of wide portions, which are alternately arranged in the second direction, and

one wide portion of the plurality of wide portions and one narrow portion of the plurality of narrow portions in an endmost second electrode formed at an end among the plurality of second electrodes are narrower than one wide portion of the plurality of wide portions and one narrow portion of the plurality of narrow portions in an inner second electrode located inside the endmost second electrode, respectively.

2. The touch panel according to claim 1, wherein

the endmost first electrode constitutes a first electrode located at both ends in the second direction among the plurality of first electrodes,

the endmost second electrode constitutes a second electrode located at both ends in the first direction among the plurality of second electrodes,

an end outline in the second direction of the endmost first electrode is formed in a straight line in the first direction, and

an end outline in the first direction of the endmost second electrode is formed in a straight line in the second direction.

3. The touch panel according to claim 1, wherein an external shape of a sensor region constructed with the plurality of first electrodes and the plurality of second electrodes is formed into a rectangular shape in plan view of the touch panel.

4. The touch panel according to claim 1, wherein

the endmost first electrode is formed into a shape in which the wide portion and the narrow portion of the inner first electrode are cut in the first direction, and

the endmost second electrode is formed into a shape in which the wide portion and the narrow portion of the inner second electrode are cut in the second direction.

5. The touch panel according to claim 1, wherein

a width in the endmost first electrode is larger than a half of a width in the inner first electrode, and

a width in the endmost second electrode is larger than a half of a width in the inner second electrode.

6. The touch panel according to claim 1, wherein

mesh density of a part of the endmost first electrode is larger than mesh density of the inner first electrode, and

mesh density of a part of the endmost second electrode is larger than mesh density of the inner second electrode.

7. The touch panel according to claim 6, wherein

a first reinforcing conductive wire is formed in a part of the endmost first electrode,

a second reinforcing conductive wire is formed in a part of the endmost second electrode, and

the first reinforcing conductive wire, the second reinforcing conductive wire, the plurality of conductive wires of the endmost first electrode, and the plurality of conductive wires of the endmost second electrode are formed so as to intersect with one another in plan view.

8. The touch panel according to claim 6, wherein

the mesh density of the part of the endmost first electrode is determined such that time constants of the endmost first electrode and the inner first electrode become equal to each other, and

the mesh density of the part of the endmost second electrode is determined such that time constants of the endmost second electrode and the inner second electrode become equal to each other.

9. The touch panel according to claim 1, wherein

a first extension wire that is conductive with the endmost first electrode is formed outside the endmost first electrode, and

a second extension wire that is conductive with the endmost second electrode is formed outside the endmost second electrode.

10. The touch panel according to claim 9, wherein

a width in the first extension wire is determined such that time constants of the endmost first electrode and the inner first electrode become equal to each other, and

a width in the second extension wire is determined such that time constants of the endmost second electrode and the inner second electrode become equal to each other.

11. The touch panel according to claim 1, wherein a dummy electrode that is not conductive with the first electrode and the second electrode is formed between two adjacent first electrodes from the plurality of first electrodes and between two adjacent second electrodes from the plurality of second electrodes.

12. The touch panel according to claim 1, wherein

lead wires are electrically connected to each of the plurality of first electrodes and each of the plurality of second electrodes, and

a ground wire is formed along the lead wires.

13. A display device comprising:

the touch panel according to claim 1; and

a display panel that displays an image.

14. The display device according to claim 13, further comprising a frame that covers peripheries of the touch panel and the display panel, and

wherein a part of the endmost first electrode is exposed from the frame.