Single layer capacitive imaging sensors

• US 9,182,861 B2
• Filed: 01/11/2013
• Issued: 11/10/2015
• 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:
  US13/740,121
• Publication Number:
  US 20130181942A1
• Time in Patent Office: 1,033 Days
• Field of Search: 345/174, 178/18.06
• US Class Current: 1/1
• 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 sensor electrodes comprises;

a first sensor electrode disposed on a first surface of a substrate and coupled to a first trace disposed outside the first sensor electrode;

a second sensor electrode disposed on the first surface of the substrate and coupled to a second trace disposed outside the second sensor electrode; and

a third sensor electrode disposed on the first surface of the substrate, wherein the third sensor electrode partially encloses the first sensor electrode by being disposed around a periphery of the first sensor electrode and by having opposing portions between which a centroid of the first sensor electrode is disposed and partially encloses the second sensor electrode by being disposed around a periphery of the second sensor electrode and by having opposing portions between which a centroid of the second sensor electrode is disposed, and at least a portion of the third sensor electrode is disposed between the first sensor electrode and the second sensor electrode,

wherein, within the sensing region, no jumper is coupled to any of the plurality of sensor electrodes,

wherein the first trace and the second trace travel through openings in the third sensor electrode, and

wherein the first trace and the second trace do not cross the third sensor electrode.

2. The capacitive imaging sensor of claim 1, wherein the third sensor electrode further comprises:

a first meander; and

a second meander that is coupled to the first meander,

wherein the first sensor electrode is disposed within at least a portion of the first meander of the third sensor electrode and the second sensor electrode is disposed within at least a portion of the second meander of the third sensor electrode.

3. The capacitive imaging sensor of claim 2, wherein the first meander has a first orientation on the first surface of the substrate and the second meander has a second orientation on the first surface of the substrate, and the first orientation is different that the second orientation.

4. The capacitive imaging sensor of claim 2, wherein third sensor electrode has a serpentine shape.

5. The capacitive imaging sensor of claim 1, wherein the portion of the third sensor electrode that partially encloses the first sensor electrode and the portion of the third sensor electrode that partially encloses the second sensor electrode each have a “

C”

shape.

6. The capacitive imaging sensor of claim 1, wherein the first sensor electrode, the second sensor electrode, and the third sensor electrode are either transmitter electrodes or receiver electrodes, and the ratio of transmitter electrodes to receiver electrodes is greater than 1.

7. The capacitive imaging sensor of claim 1, wherein the first sensor electrode, the second sensor electrode, and the third sensor electrode are either transmitter electrodes or receiver electrodes, and the ratio of receiver electrodes to transmitter electrodes is greater than 1.

8. The capacitive imaging sensor of claim 1, wherein at least a portion of the first and second sensor electrodes are interdigitated with a portion of the third sensor electrode.

9. The capacitive imaging sensor of claim 1, wherein the first sensor electrode, the second sensor electrode and the third sensor electrode each comprise a trace that is coupled to a sensor processor.

10. The capacitive imaging sensor of claim 1, wherein the first sensor electrode, the second sensor electrode and the third sensor electrode are optically clear.

11. The capacitive imaging sensor of claim 1, wherein the substrate is coupled to a display.

12. The capacitive image sensor of claim 1, wherein:

the first sensor electrode and the second sensor electrode have a zig-zag wire shape.

13. 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 sensor electrodes comprises;

a first sensor electrode disposed on a first surface of a substrate and coupled to a first trace disposed outside the first sensor electrode;

a second sensor electrode disposed on the first surface of the substrate and coupled to a second trace disposed outside the second sensor electrode; and

a third sensor electrode disposed on the first surface of the substrate, wherein the third sensor electrode is disposed between the first sensor electrode and the second sensor electrode, the third sensor electrode partially encloses the first sensor electrode by being disposed around a periphery of the first sensor electrode and by having opposing portions between which a centroid of the first sensor electrode is disposed and partially encloses the second sensor electrode by being disposed around a periphery of the second sensor electrode and by having opposing portions between which a centroid of the second sensor electrode is disposed, and the third sensor electrode is interdigitated with the first sensor electrode and interdigitated with the second sensor electrode,

wherein, within the sensing region, no jumper is coupled to any of the plurality of sensor electrodes,

wherein the first trace and the second trace travel through openings in the third sensor electrode, and

wherein the first trace and the second trace do not cross the third sensor electrode.

14. The capacitive imaging sensor of claim 13, wherein the first sensor electrode, the second sensor electrode, and the third sensor electrode are either transmitter electrodes or receiver electrodes, and the ratio of transmitter electrodes to receiver electrodes is greater than 1.

15. The capacitive imaging sensor of claim 13, wherein the first sensor electrode, the second sensor electrode, and the third sensor electrode are either transmitter electrodes or receiver electrodes, and the ratio of receiver electrodes to transmitter electrodes is greater than 1.

16. The capacitive imaging sensor of claim 13, wherein the first sensor electrode, the second sensor electrode and the third sensor electrode each comprise a trace that is coupled to a sensor processor.

17. The capacitive imaging sensor of claim 13, wherein the first sensor electrode, the second sensor electrode and the third sensor electrode are optically clear.

18. The capacitive imaging sensor of claim 13, wherein the substrate is coupled to a display.

19. A touch screen, comprising:

a plurality of sensor electrodes disposed on a substrate 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 the substrate and coupled to a first trace disposed outside the first sensor electrode;

a second sensor electrode disposed on the first surface of the substrate and coupled to a second trace disposed outside the second sensor electrode; and

a third sensor electrode disposed on the first surface of the substrate, wherein the third sensor electrode partially encloses the first sensor electrode by being disposed around a periphery of the first sensor electrode and by having opposing portions between which a centroid of the first sensor electrode is disposed and partially encloses the second sensor electrode by being disposed around a periphery of the second sensor electrode and by having opposing portions between which a centroid of the second sensor electrode is disposed, and at least a portion of the third sensor electrode is disposed between the first sensor electrode and the second sensor electrode; and

a sensor processor communicatively coupled to the first, second and third sensor electrodes, and configured to receive resulting signals received by the third sensor electrode when either the first or second sensor electrode is driven for capacitive sensing, wherein the sensor processor comprises a first receiver channel coupled to the third receiver electrode,

wherein, within the sensing region, no jumper is coupled to any of the plurality of sensor electrodes,

wherein the first trace and the second trace travel through openings in the third sensor electrode, and

wherein the first trace and the second trace do not cross the third sensor electrode.

20. The capacitive imaging sensor of claim 19, wherein the first sensor electrode, the second sensor electrode and the third sensor electrode each comprise a trace that is coupled to a sensor processor.

21. The capacitive imaging sensor of claim 19, wherein the substrate is coupled to a display.