Single layer sensor pattern

• US 9,658,726 B2
• Filed: 06/15/2015
• Issued: 05/23/2017
• Est. Priority Date: 07/10/2014
• Status: Active Grant

• Current Assignee: Cypress Semiconductor Corporation (Infineon Technologies AG)
• Original Assignee: Cypress Semiconductor Corporation (Infineon Technologies AG)
• Inventors: Rowe, Gabriel, Wang, Chuanwei
• Primary Examiner(s): Spar, Ilana
• Assistant Examiner(s): Truong, Nguyen H
• Application Number:
  US14/740,170
• Publication Number:
  US 20160011690A1
• Time in Patent Office: 708 Days
• CPC Class Codes: G06F 3/04164 Connections between sensors and controllers, e.g. routing lines between electrodes and connection pads
• CPC Class Codes: G06F 3/041662 using alternate mutual and self-capacitive scanning
• CPC Class Codes: G06F 3/0443 using a single layer of sensing electrodes
• 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

Abstract

A capacitive sensor array comprises large sensor electrodes and small sensor electrodes formed from a single layer of conductive material. Each sensor electrode of a first set of small sensor electrodes is electrically connected to a first pad. A first axis crosses two or more of the sensor electrodes of the first set of small sensor electrodes, and each small sensor electrode of the first set of small sensor electrodes is located on an opposite lateral side of one of the large sensor electrodes from another small sensor electrode of the first set. Each sensor electrode of a second set of small sensor electrodes is electrically connected to a second pad. A second axis crosses two or more of the sensor electrodes of the second set of small sensor electrodes, and each small sensor electrode of the second set is located on an opposite lateral side of one of the large sensor electrodes from another small sensor electrode of the second set.

Claims

1. A capacitive sensor array, comprising:

a plurality of large sensor electrodes located within an active sensing region;

a plurality of small sensor electrodes including a first set of at least four small sensor electrodes and a second set of at least four small sensor electrodes located within the active sensing region, wherein the plurality of large sensor electrodes and the plurality of small sensor electrodes are formed from a single layer of conductive material; and

a plurality of pads located within an edge region bordering the active sensing region,

wherein each small sensor electrode of the first set of small sensor electrodes is electrically connected by a first conductive path through a first set of connecting traces to a first pad of the plurality of pads, wherein a first axis crosses two or more of the small sensor electrodes of the first set of small sensor electrodes, wherein each small sensor electrode of the first set of small sensor electrodes is located on an opposite lateral side of one of the plurality of large sensor electrodes from another small sensor electrode of the first set of small sensor electrodes,

wherein each small sensor electrode of the second set of small sensor electrodes is electrically connected by a second conductive path through a second set of connecting traces to a second pad of the plurality of pads, wherein the first conductive path is non-overlapping with the second conductive path, wherein a second axis crosses two or more of the small sensor electrodes of the second set of small sensor electrodes, wherein each small sensor electrode of the second set of small sensor electrodes is located on an opposite lateral side of one of the plurality of large sensor electrodes from another small sensor electrode of the second set of small sensor electrodes, wherein a first segment of the first conductive path extends from the edge region to a routing region on a first lateral side of a second segment of the first conductive path, and extends back to the edge region on a second lateral side of the second segment opposite the first lateral side of the second segment prior to returning to the routing region, wherein the routing region borders the active sensing region on an opposite side of the active sensing region from the edge region.

2. The capacitive sensor array of claim 1, wherein for each small sensor electrode of the plurality of sensor electrodes, a shortest line segment between a geometric center of the small sensor electrode and a central longitudinal axis of a large sensor electrode nearest to the geometric center crosses a ground trace and does not cross any other small electrode.

3. The capacitive sensor array of claim 1, wherein the first pad is connected at opposite ends of the first pad to two connecting traces of the first set of connecting traces, and wherein the second pad is connected at opposite ends of the second pad to two connecting traces of the second set of connecting traces.

4. The capacitive sensor array of claim 1, wherein the plurality of pads comprises a pad for each large sensor electrode of the plurality of large sensor electrodes and for each of a plurality of sets of small sensor electrodes, wherein each small sensor electrode in the plurality of sets of small sensor electrodes is electrically connected to every other small sensor electrode in the same set of small sensor electrodes by a set of connecting traces, and wherein the plurality of sets of small sensor electrodes comprises the first set of sensor electrodes and the second set of sensor electrodes.

5. The capacitive sensor array of claim 4, further comprising one or more ground traces in the active sensing region, wherein a number of pads in the edge region is less than or equal to one pad for each large sensor electrode of the plurality of sensor electrodes, for each set of small sensor electrodes of the plurality of small sensor electrodes, and for each of the one or more ground traces.

6. The capacitive sensor array of claim 1, wherein a third axis perpendicular to the first axis and the second axis crosses at least one of the first set of small sensor electrodes and at least one of the second set of small sensor electrodes.

7. The capacitive sensor array of claim 6, wherein a fourth axis parallel to the third axis crosses two or more of the plurality of large sensor electrodes.

8. The capacitive sensor array of claim 7, further comprising one or more additional sets of small sensor electrodes, wherein each small sensor electrode in the one or more additional sets of small sensor electrodes is electrically coupled to every other small sensor electrode in the same set of small sensor electrodes by a set of connecting traces, wherein for each of the two or more large sensor electrodes crossed by the fourth axis, the third axis crosses one small sensor electrode from each of the additional sets of small sensor electrodes.

9. A capacitive sensor array, comprising:

a plurality of large sensor electrodes located within an active sensing region;

a plurality of small sensor electrodes including a first set of small sensor electrodes and a second set of small sensor electrodes located within the active sensing region, wherein the plurality of large sensor electrodes and the plurality of small sensor electrodes are formed from a single layer of conductive material; and

a plurality of pads located within an edge region bordering the active sensing region,

wherein a first segment of a first conductive path through each of the first set of small electrodes

extends, on a first lateral side of a second segment of the first conductive path, from a first pad of the plurality of pads to a routing region on an opposite side of the active sensing region from the edge region, and

extends, on a second lateral side of the second segment opposite the first lateral side of the second segment, from the routing region back to the edge region prior to returning to the routing region,

wherein a first axis crosses two or more of the small sensor electrodes of the first set of small sensor electrodes, wherein each small sensor electrode of the first set of small sensor electrodes is located on an opposite lateral side of one of the plurality of large sensor electrodes from another small sensor electrode of the first set of small sensor electrodes,

wherein a second conductive path through each of the second set of small electrodes is non-overlapping with the first conductive path and extends from a second pad of the plurality of pads to a routing region opposite the edge region, and extends from the routing region back to the edge region prior to returning to the routing region, wherein a second axis crosses two or more of the small sensor electrodes of the second set of small sensor electrodes, wherein each small sensor electrode of the second set of small sensor electrodes is located on an opposite lateral side of one of the plurality of large sensor electrodes from another small sensor electrode of the second set of small sensor electrodes.

10. The capacitive sensor array of claim 9, wherein for each small sensor electrode of the plurality of sensor electrodes, a shortest line segment between a geometric center of the small sensor electrode and a central longitudinal axis of a large sensor electrode nearest to the geometric center crosses a ground trace and does not cross any other small electrode.

11. The capacitive sensor array of claim 9, wherein the first pad is connected at opposite ends of the first pad to two connecting traces of the first set of connecting traces, and wherein the second pad is connected at opposite ends of the second pad to two connecting traces of the second set of connecting traces.

12. The capacitive sensor array of claim 9, wherein the plurality of pads comprises a pad for each large sensor electrode of the plurality of large sensor electrodes and for each of a plurality of sets of small sensor electrodes, wherein each small sensor electrode in the plurality of sets of small sensor electrodes is electrically connected to every other small sensor electrode in the same set of small sensor electrodes by a set of connecting traces, and wherein the plurality of sets of small sensor electrodes comprises the first set of sensor electrodes and the second set of sensor electrodes.

13. The capacitive sensor array of claim 9, further comprising a plurality of sets of small sensor electrodes, wherein the plurality of sets of small sensor electrodes comprises the first set of small sensor electrodes and the second set of small sensor electrodes, wherein each small sensor electrode in the plurality of sets of small sensor electrodes is electrically coupled to every other small sensor electrode in the same set of small sensor electrodes by a set of connecting traces, wherein a third axis perpendicular to the first axis and the second axis crosses two or more of the plurality of large sensor electrodes, wherein for each of the two or more large sensor electrodes crossed by the third axis, a fourth axis parallel to the third axis crosses one small sensor electrode from each of the plurality of sets of small sensor electrodes.

14. A method, comprising:

providing a plurality of large sensor electrodes located within an active sensing region;

providing a plurality of small sensor electrodes including a first set of at least four small sensor electrodes and a second set of at least four small sensor electrodes located within the active sensing region, wherein the plurality of large sensor electrodes and the plurality of small sensor electrodes are formed from a single layer of conductive material; and

providing a plurality of pads coupled with the capacitance sensor and located within an edge region bordering the active sensing region;

wherein each small sensor electrode of the first set of small sensor electrodes is electrically connected by a first conductive path through a first set of connecting traces to a first pad of the plurality of pads, wherein a first axis crosses two or more of the small sensor electrodes of the first set of small sensor electrodes, wherein each small sensor electrode of the first set of small sensor electrodes is located on an opposite lateral side of one of the plurality of large sensor electrodes from another small sensor electrode of the first set of small sensor electrodes,

wherein each small sensor electrode of the second set of small sensor electrodes is electrically connected by a second conductive path through a second set of connecting traces to a second pad of the plurality of pads, wherein the first set of conductive paths is non-overlapping with the second set of conductive paths, wherein a second axis crosses two or more of the small sensor electrodes of the second set of small sensor electrodes, wherein each small sensor electrode of the second set of small sensor electrodes is located on an opposite lateral side of one of the plurality of large sensor electrodes from another small sensor electrode of the second set of small sensor electrodes, wherein a first segment of the first conductive path extends from the edge region to a routing region on a first lateral side of a second segment of the first conductive path, and extends back to the edge region on a second lateral side of the second segment opposite the first lateral side of the second segment prior to returning to the routing region, wherein the routing region borders the active sensing region on an opposite side of the active sensing region from the edge region.

15. The method of claim 14, further comprising providing one or more ground traces in the active sensing region, wherein a number of the plurality of pads in the edge region is less than or equal to one pad for each large sensor electrode of the plurality of sensor electrodes, for each set of electrically connected small sensor electrodes of the plurality of small sensor electrodes, and for each of the one or more ground traces.

16. The method of claim 14, wherein the plurality of pads comprises a pad for each large sensor electrode of the plurality of large sensor electrodes and for each of a plurality of sets of small sensor electrodes, wherein each small sensor electrode in the plurality of sets of small sensor electrodes is electrically coupled to every other small sensor electrode in the same set of small sensor electrodes by a set of connecting traces, wherein the plurality of sets of small sensor electrodes comprises the first set of sensor electrodes and the second set of sensor electrodes.

17. The capacitive sensor array of claim 14, wherein for each small sensor electrode of the plurality of sensor electrodes, a shortest line segment between a geometric center of the small sensor electrode and a central longitudinal axis of a large sensor electrode nearest to the geometric center crosses a ground trace and does not cross any other small electrode, and wherein the first pad is connected at opposite ends of the first pad to two connecting traces of the first set of connecting traces, and wherein the second pad is connected at opposite ends of the second pad to two connecting traces of the second set of connecting traces.

18. The capacitive sensor array of claim 14, wherein a third axis perpendicular to the first axis and the second axis crosses at least one of the first set of small sensor electrodes and at least one of the second set of small sensor electrodes, and wherein a fourth axis parallel to the third axis crosses two or more of the plurality of large sensor electrodes.