Single layer capacitive imaging sensors

• US 9,817,533 B2
• Filed: 10/20/2015
• Issued: 11/14/2017
• Est. Priority Date: 01/12/2012
• Status: Active Grant

• Current Assignee: Synaptics Incorporated
• Original Assignee: Synaptics Incorporated
• Inventors: Bulea, Mihai, Solven, Derek, Reynolds, Joseph Kurth, Hoch, David, Dattalo, Tracy Scott
• Primary Examiner(s): Nguyen, Kevin M
• Application Number:
  US14/918,496
• Publication Number:
  US 20160041654A1
• Time in Patent Office: 756 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 3/041 Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
• CPC Class Codes: G06F 3/04164 Connections between sensors and controllers, e.g. routing lines between electrodes and connection pads
• CPC Class Codes: G06F 3/0443 using a single layer of sensing 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

Embodiments of the invention generally provide an input device that includes a plurality of sensing elements that are interconnected in desired way to acquire positional information of an input object, so that the acquired positional information can be used by other system components to control a display or other useful system components. One or more of the embodiments described herein, utilizes one or more of the techniques and sensor electrode array configuration disclosed herein to reduce or minimize the number of traces and/or electrodes required to sense the position of an input object within a sensing region of the input device.

Claims

1. A capacitive image sensor, comprising:

a plurality of sensor electrodes that are disposed within a sensing region, wherein the sensing region includes a plurality of unit cells of a sensing pattern, and wherein a subset of the plurality of sensor electrodes comprises;

a first sensor electrode disposed on a first surface of a substrate, the first sensor electrode having a first dimension and a second dimension substantially perpendicular to the first dimension, the first dimension being greater than the second dimension, wherein the first sensor electrode includes a plurality of fingers protruding in the second dimension, and wherein the plurality of fingers are connected by a plurality of connecting segments, the plurality of connecting segments being continuous, angled, and alternating in angle in a lengthwise direction along the first dimension, and wherein adjacent subsets of the plurality of fingers, protruding from adjacent alternating connecting segments, protrude in opposite directions in the second dimension; and

two or more sensor electrodes of the subset of the plurality of sensor electrodes, the two or more sensor electrodes disposed adjacent to the first sensor electrode and on the first surface of the substrate, each of the two or more sensor electrodes being interdigitated with a different one of the subsets of the plurality of fingers in the alternating directions in the second dimension of the first sensor electrode, wherein, within the sensing region, no jumper is coupled to any of the plurality of sensor electrodes, and wherein the first sensor electrode encloses the two or more sensor electrodes in the second dimension and substantially encloses the two or more sensor electrodes in the first dimension.

2. The capacitive imaging sensor of claim 1, wherein each of the two or more sensor electrodes being are interdigitated with one of the subsets of the plurality of fingers such that each of the two or more sensor electrodes overlaps the first sensor electrode in the second dimension.

3. The capacitive imaging sensor of claim 1, wherein the first sensor electrode is wider than each of the two or more sensor electrodes.

4. The capacitive imaging sensor of claim 1, wherein the two or more sensor electrodes are disposed adjacent to one another along the first dimension.

5. The capacitive imaging sensor of claim 1, wherein each of the two or more sensor electrodes has recess regions in which the interdigitation occurs.

6. The capacitive imaging sensor of claim 1, wherein the two or more sensor electrodes comprise receiver electrodes and the first sensor electrode comprises a transmitter electrode.

7. The capacitive image sensor of claim 1, wherein at least first and second routing traces for the two or more sensor electrodes and a third routing trace for the first sensor electrode are each connected from a first end of the capacitive image sensor in the first dimension.

8. A capacitive image sensor, comprising:

an array of sensing patterns, each sensing pattern comprising;

a first sensor electrode disposed on a first surface of a substrate, the first sensor electrode having a first dimension that is substantially perpendicular to, and greater than, a second dimension, the first sensor electrode having a plurality of fingers protruding in the second dimension, wherein the plurality of fingers are connected by a plurality of connecting segments, the plurality of connecting segments being continuous, angled, and alternating in angle in a lengthwise direction along the first dimension, and wherein adjacent subsets of the plurality of fingers, protruding from adjacent alternating connecting segments, protrude in opposite directions in the second dimension;

two or more sensor electrodes disposed adjacent to the first sensor electrode on the first surface of the substrate, each of the two or more sensor electrodes having a second plurality of fingers that are interdigitated with a different one of the subsets of the plurality of fingers in the alternating directions in the second dimension,

wherein the first sensor electrode encloses the two or more sensor electrodes in the second dimension and substantially encloses the two or more sensor electrodes in the first dimension; and

wherein the first sensor electrode and the two or more sensor electrodes are independently routed.

9. The capacitive image sensor of claim 8, wherein the first plurality of fingers and the two or more sensor electrodes are interdigitated in an overlap area that is longer in the second dimension than in the first dimension.

10. The capacitive image sensor of claim 8, wherein the two or more sensor electrodes are disposed adjacent along the first dimension.

11. The capacitive image sensor of claim 8, wherein:

the first sensor electrode is wider than each of the two or more sensor electrodes.

12. The capacitive image sensor of claim 8, wherein the first sensor electrode comprises a transmitter electrode and the two or more sensor electrodes comprise receiver electrodes.

13. The capacitive image sensor of claim 8, wherein a first routing trace for the first sensor electrode and at least second and third routing traces for the two or more sensor electrodes are each connected from a first end of the capacitive image sensor in the first dimension.

14. A processing system, comprising:

a signal generating processor configured to drive one or more of a first sensor electrode, a second sensor electrode, and a third sensor electrode with a signal for capacitive sensing; and

a sensor processor configured to receive resulting signals with one or more of the first sensor electrode, the second sensor electrode, and the third sensor electrode, the resulting signals comprising effects related to the signal,

wherein the first sensor electrode is disposed on a first surface of a substrate of a capacitive image sensor, the first sensor electrode having a first dimension that is substantially perpendicular to, and greater than, a second dimension, the first sensor electrode having a first plurality of fingers,

wherein the plurality of fingers are connected by a plurality of connecting segments, the plurality of connecting segments being continuous, angled, and alternating in angle in a lengthwise direction along the first dimension,

wherein adjacent subsets of the plurality of fingers, protruding from adjacent alternating connecting segments, protrude in opposite directions in the second dimension,

wherein the second sensor electrode is disposed on the first surface of the substrate, the second sensor electrode being interdigitated with a first subset of the plurality of fingers in a first direction in the second dimension,

wherein the third sensor electrode is disposed on the first surface of the substrate, the third sensor electrode being interdigitated with a different subset the plurality of fingers in a second an opposite direction in the second dimension,

wherein the first sensor electrode encloses the second and third sensor electrodes in the second dimension and substantially encloses the second and third sensor electrodes in the first dimension, and

wherein the first sensor electrode, the second sensor electrode, and the third sensor electrode are independently routed.

15. The processing system of claim 14, wherein the first sensor electrode is wider than each of the second sensor electrode and the third sensor electrode.

16. The processing system of claim 14, wherein a first routing trace for the first sensor electrode, a second routing trace for the second sensor electrode, and a third routing trace for the third sensor electrode are each connected from a first end of the capacitive image sensor in the first dimension.