Capacitive touch sensor with Z-shaped electrode pattern

• US 9,958,999 B2
• Filed: 04/01/2015
• Issued: 05/01/2018
• Est. Priority Date: 04/17/2014
• Status: Active Grant

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Chen, Chi-Fan, Barton, Roger W., Frey, Matthew H.
• Primary Examiner(s): Sarma, Abhishek
• Application Number:
  US15/129,033
• Publication Number:
  US 20170177112A1
• Time in Patent Office: 1,126 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 3/04164 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 3/0448 Details of the electrode shape, e.g. for enhancing the detection of touches, for generating specific electric field shapes, for enhancing display quality

Abstract

Designs for touch sensor circuitry and touch sensor incorporating such circuitry are described. More particularly, touch sensor circuitry including multiple elongate electrodes that are interleaved with one another is described.

Claims

1. A first array of elongate, electrically isolated conductive electrodes disposed on a first major surface of a first substrate for use in a touch sensor, comprising:

a first electrode;

a second electrode; and

a third electrode, wherein

each of the first electrode, second electrode, and third electrode comprises a proximate end and a distal end,

each of the first electrode, second electrode, and third electrode has a z-shape, wherein the z-shape includes a first elongate section, second elongate section, and a third elongate section, and wherein the elongate sections are oriented parallel to one another,

the first electrode is interleaved with the second electrode, and

the second electrode is interleaved with the third electrode.

2. The array of claim 1, wherein each of the first electrode, second electrode, and third electrode is connected at its proximate end to a touch controller circuit.

3. The array of claim 2, wherein each of the first electrode, second electrode, and third electrode is also connected at its distal end to the touch controller circuit.

4. The array of claim 1, wherein the first electrode is connected at its proximate end to a touch controller circuit, the first electrode is not connected at its distal end to the touch controller circuit, the second electrode is connected at its distal end to the touch controller circuit, and the second electrode is not connected at its proximate end to the touch controller circuit.

5. The array of claim 1, wherein the first elongate section of the second electrode is disposed between the second and third elongate sections of the first electrode, and the third elongate section of the second electrode is disposed between the first and second elongate sections of the third electrode.

6. The array of claim 2, wherein the connection between the touch controller circuit and the electrode at the proximate end of each electrode occurs between the first and second parallel elongate sections of each electrode.

7. The array of claim 1, wherein the electrodes are comprised of one or a combination of a transparent conductive material, a transparent conductive composite, a transparent conductive multilayer, and a transparent conductive mesh network of traces.

8. The array of claim 7, wherein the electrodes are comprised of transparent conductive mesh network of traces.

9. A touch sensor comprising the array of claim 1.

10. A sensor system comprising a stylus and the touch sensor of claim 9, wherein the distance between the first elongate section of the second electrode and the second elongate section of the first electrode is less than 4 times the diameter of a tip of the stylus.

11. A touch sensor comprising the first substrate and the first array of claim 1, further comprising a second array of elongate, electrically isolated conductive electrodes disposed on a second major surface of the first substrate opposite the first major surface of the first substrate, comprising:

a fourth electrode;

a fifth electrode; and

a sixth electrode, wherein

each of the fourth electrode, fifth electrode, and sixth electrode comprises a proximate end and a distal end,

each of the fourth electrode, fifth electrode, and sixth electrode has a z-shape, wherein the z-shape includes a first elongate section, second elongate section, and a third elongate section, and wherein the elongate sections are oriented parallel to one another,

the fourth electrode is interleaved with the fifth electrode, and

the fifth electrode is interleaved with the sixth electrode.

12. The touch sensor of claim 11, wherein

the first electrode, second electrode, and third electrode are oriented in a first direction;

the fourth electrode, fifth electrode, and sixth electrode are oriented in a second direction;

the first direction is orthogonal to the second direction; and

the first array overlaps the second array.

13. A touch sensor comprising the first substrate and the array of claim 1, further comprising a second array of elongate, electrically isolated conductive electrodes disposed on a second major surface of a second substrate, comprising:

a fourth electrode;

a fifth electrode; and

a sixth electrode, wherein

each of the fourth electrode, fifth electrode, and sixth electrode comprises a proximate end and a distal end,

each of the fourth electrode, fifth electrode, and sixth electrode has a z-shape, wherein the z-shape includes a first elongate section, second elongate section, and a third elongate section, and wherein the elongate sections are oriented parallel to one another,

the fourth electrode is interleaved with the fifth electrode, and

the fifth electrode is interleaved with the sixth electrode.

14. The touch sensor of claim 13, wherein

the first electrode, second electrode, and third electrode are oriented in a first direction;

the fourth electrode, fifth electrode, and sixth electrode are oriented in a second direction;

the first direction is orthogonal to the second direction; and

the first array overlaps the second array.

15. The touch sensor of claim 13, wherein

the first electrode, second electrode, and third electrode are oriented in a first direction;

the fourth electrode, fifth electrode, and sixth electrode are oriented in a second direction;

the first direction is not parallel to the second direction; and

the first array overlaps the second array.

16. The array of claim 1, wherein the width of each of the first and third elongate sections of the electrodes is less than the width of each of the second elongate sections of the electrodes.

17. The array of claim 7, wherein the electrodes are comprised of transparent conductive material.

18. The array of claim 17, wherein the transparent conductive material comprises indium tin oxide, zinc oxide, fluorine doped tin oxide, conductive polymer, or graphene.

19. The array of claim 8, wherein the mesh network of traces has a sheet resistance between 0.2 and 100 ohms per square.

20. The array of claim 8, wherein the traces comprises one or more of copper, silver, gold, aluminum, zinc, nickel and iron.