Touch Sensor Including Mutual Capacitance Electrodes and Self-Capacitance Electrodes

• US 20130154996A1
• Filed: 12/16/2011
• Published: 06/20/2013
• Est. Priority Date: 12/16/2011
• Status: Abandoned Application

• Current Assignee: Atmel Corporation (Microchip Technology Incorporated)
• Original Assignee: Atmel Corporation (Microchip Technology Incorporated)
• Inventors: Trend, Matthew, Clements, Paul
• Application Number:
  US13/328,967
• Publication Number:
  US 20130154996A1
• Time in Patent Office: Days
• US Class Current: 345/174
• CPC Class Codes: G06F 2203/04111 Cross over in capacitive digitiser, i.e. details of structures for connecting electrodes of the sensing pattern where the connections cross each other, e.g. bridge structures comprising an insulating layer, or vias through substrate
• CPC Class Codes: G06F 3/0443 using a single layer of sensing electrodes
• 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: H03K 17/9622 using a plurality of detectors, e.g. keyboard
• CPC Class Codes: H03K 2217/960775 Emitter-receiver or "fringe" type detection, i.e. one or more field emitting electrodes and corresponding one or more receiving electrodes

Abstract

According to one embodiment, a touch sensor has a first edge and a second edge approximately perpendicular to the first edge. The touch sensor includes a first plurality of electrodes approximately parallel to the first edge, a second plurality of electrodes approximately parallel to the second edge, and a first plurality of nodes. Each of the first plurality of nodes are formed by a capacitive coupling between an electrode of the first plurality of electrodes and an electrode of the second plurality of electrodes. The touch sensor further includes a third plurality of electrodes and a second node formed by the third plurality of electrodes. Each of the third plurality of electrodes form a portion of the second node by a self-capacitance coupling. At least one of the portions of the second node is positioned in-between at least two of the first plurality of nodes.

Claims

1. A touch sensor having a first edge and a second edge approximately perpendicular to the first edge, the touch sensor comprising:

a first plurality of electrodes approximately parallel to the first edge;

a second plurality of electrodes approximately parallel to the second edge;

a first plurality of nodes, each of the first plurality of nodes formed by a capacitive coupling between an electrode of the first plurality of electrodes and an electrode of the second plurality of electrodes;

a third plurality of electrodes;

a second node formed by the third plurality of electrodes, each of the third plurality of electrodes forming a portion of the second node by a self-capacitance coupling; and

wherein at least one of the portions of the second node is positioned in-between at least two of the first plurality of nodes.

2. The touch sensor of claim 1, wherein:

the second plurality of electrodes are each separated from each other by a gap; and

the third plurality of electrodes are positioned in the plurality of gaps.

3. The touch sensor of claim 1, wherein:

the first plurality of electrodes are each separated from each other by a gap; and

the third plurality of electrodes are positioned in the plurality of gaps.

4. The touch sensor of claim 1, wherein:

each of the first plurality of electrodes is operable to pulse a first electric field towards one or more of the second plurality of electrodes;

each of the third plurality of electrodes is operable to pulse a second electric field through a cover panel positioned over the touch sensor; and

the pulses of the first electric fields are alternatingly synchronized with the pulses of the second electric fields to prevent interference.

5. The touch sensor of claim 1, wherein each of the third plurality of electrodes is positioned so as not to interfere with one or more pulses of an electric field from each of the first plurality of electrodes.

6. A touch sensor having a first edge and a second edge approximately perpendicular to the first edge, the touch sensor comprising:

a first plurality of electrodes, wherein at least one of the first plurality of electrodes comprises a hollowed out portion;

a second plurality of electrodes;

a first plurality of nodes, each of the first plurality of nodes formed by a capacitive coupling between an electrode of the first plurality of electrodes and an electrode of the second plurality of electrodes;

a third plurality of electrodes, wherein at least one of the third plurality of electrodes is positioned in the hollowed out portion of the at least one of the first plurality of electrodes; and

a second node formed by the third plurality of electrodes, each of the third plurality of electrodes forming a portion of the second node by a self-capacitance coupling.

7. The touch sensor of claim 6, wherein:

each of the first plurality of electrodes comprises a portion that is hollowed out; and

the plurality of third electrodes are positioned in the plurality of hollowed out portions.

8. The touch sensor of claim 6, wherein:

at least one of the second plurality of electrodes comprises a hollowed out portion; and

at least a second electrode of the third plurality of electrodes is positioned in the hollowed out portion of the at least one of the second plurality of electrodes.

9. The touch sensor of claim 6, further comprising a substrate comprising a top side and a bottom side, wherein the first plurality of electrodes are positioned on the bottom side of the substrate, wherein the second plurality of electrodes are positioned on the top side of the substrate.

10. The touch sensor of claim 6, wherein each of the second plurality of electrodes comprises a plurality of conductive elements arranged in a snowflake design.

11. A device, comprising:

a controller; and

a touch sensor having a first edge and a second edge approximately perpendicular to the first edge, the touch sensor coupled to the controller, the touch sensor comprising;

a first plurality of electrodes approximately parallel to the first edge;

a second plurality of electrodes approximately parallel to the second edge;

a first plurality of nodes, each of the first plurality of nodes formed by a capacitive coupling between an electrode of the first plurality of electrodes and an electrode of the second plurality of electrodes;

a third plurality of electrodes;

a second node formed by the third plurality of electrodes, each of the third plurality of electrodes forming a portion of the second node by a self-capacitance coupling; and

wherein at least one of the portions of the second node is positioned in-between at least two of the first plurality of nodes.

12. The device of claim 11, wherein:

the second plurality of electrodes are each separated from each other by a gap; and

the third plurality of electrodes are positioned in the plurality of gaps.

13. The device of claim 11, wherein:

the first plurality of electrodes are each separated from each other by a gap; and

the third plurality of electrodes are positioned in the plurality of gaps.

14. The device of claim 11, wherein:

each of the first plurality of electrodes is operable to pulse a first electric field towards one or more of the second plurality of electrodes;

each of the third plurality of electrodes is operable to pulse a second electric field through a cover panel positioned over the touch sensor; and

the pulses of the first electric fields are alternatingly synchronized with the pulses of the second electric fields to prevent interference.

15. The device of claim 11, wherein each of the third plurality of electrodes is positioned so as not to interfere with one or more pulses of an electric field from each of the first plurality of electrodes.

16. A device, comprising:

a controller; and

a touch sensor having a first edge and a second edge approximately perpendicular to the first edge, the touch sensor coupled to the controller, the touch sensor comprising;

a first plurality of electrodes, wherein at least one of the first plurality of electrodes comprises a hollowed out portion;

a second plurality of electrodes;

a first plurality of nodes, each of the first plurality of nodes formed by a capacitive coupling between an electrode of the first plurality of electrodes and an electrode of the second plurality of electrodes;

a third plurality of electrodes, wherein at least one of the third plurality of electrodes is positioned in the hollowed out portion of the at least one of the first plurality of electrodes; and

a second node formed by the third plurality of electrodes, each of the third plurality of electrodes forming a portion of the second node by a self-capacitance coupling.

17. The device of claim 16, wherein:

each of the first plurality of electrodes comprises a portion that is hollowed out; and

the plurality of third electrodes are positioned in the plurality of hollowed out portions.

18. The device of claim 16, wherein:

at least one of the second plurality of electrodes comprises a hollowed out portion; and

at least a second electrode of the third plurality of electrodes is positioned in the hollowed out portion of the at least one of the second plurality of electrodes.

19. The device of claim 16, further comprising a substrate comprising a top side and a bottom side, wherein the first plurality of electrodes are positioned on the bottom side of the substrate, wherein the second plurality of electrodes are positioned on the top side of the substrate.

20. The device of claim 16, wherein each of the second plurality of electrodes comprises a plurality of conductive elements arranged in a snowflake design.