SINGLE LAYER CAPACITIVE IMAGING SENSORS

• US 20130181943A1
• Filed: 01/11/2013
• Published: 07/18/2013
• 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
• Granted Patent: US 9,081,453 B2
• Time in Patent Office: Days
• US Class Current: 345/174
• 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 first set of sensor electrodes comprising a first sensor electrode, a second sensor electrode and a third sensor electrode, and the first sensor electrode is electrically coupled to the third sensor electrode; and

a second set of sensor electrodes comprising a fourth sensor electrode and a fifth sensor electrode, wherein the fourth sensor electrode is configured to capacitively couple with the first sensor electrode, and the fifth sensor electrode is configured to capacitively couple with the third sensor electrode.

2. The capacitive imaging sensor of claim 1, wherein the second sensor electrode is disposed between the first sensor electrode and the third sensor electrode.

3. The capacitive imaging sensor of claim 1, wherein the third sensor electrode is disposed between the first sensor electrode and the second sensor electrode.

4. The capacitive imaging sensor of claim 1, wherein

the second set of sensor electrodes further comprises a sixth sensor electrode that is disposed between the fourth and fifth sensor electrodes, and

the second sensor electrode is disposed between the first sensor electrode and the third sensor electrode, and the second sensor electrode is configured to capacitively couple with the fourth sensor electrode and the sixth sensor electrode.

5. The capacitive imaging sensor of claim 1, further comprising:

an array of sensor electrodes comprising the first and the second sets of sensor electrodes, wherein the array of sensor electrodes comprises transmitter electrodes and receiver electrodes, and the ratio of transmitter electrodes to receiver electrodes is greater than 1.

6. The capacitive imaging sensor of claim 1, further comprising:

an array of sensor electrodes comprising the first and the second sets of sensor electrodes, wherein the array of sensor electrodes comprises transmitter electrodes and receiver electrodes, and the ratio of receiver electrodes to transmitter electrodes is greater than 1.

7. The capacitive imaging sensor of claim 1, wherein the first set of sensor electrodes further comprises:

a first group of sensor electrodes that comprises a plurality of the first sensor electrodes which are disposed in a staggered arrangement across a center line,

a second group of sensor electrodes that comprises a plurality of the second sensor electrodes which are disposed in a staggered arrangement across the center line, and

a third group of sensor electrodes that comprises a plurality of the third sensor electrodes which are disposed in a staggered arrangement across the center line.

8. The capacitive imaging sensor of claim 1, wherein the first set of sensor electrodes further comprises:

a trace that electrically couples the first sensor electrode to the third sensor electrode.

9. The capacitive imaging sensor of claim 1, wherein the third sensor electrode has a first region and a second region, wherein each first region has an area density that is greater than the second region, and the first sensor electrode is disposed adjacent to the first region and the second sensor electrode is disposed adjacent to the second region.

10. The capacitive imaging sensor of claim 1, wherein the first sensor electrode and the second sensor electrode are disposed adjacent to an edge of the fourth sensor electrode and the third sensor electrode is disposed adjacent to an edge of the fifth sensor electrode, and

wherein the edge of the fourth sensor electrode and the edge of the fifth sensor electrode are aligned at an angle less than or greater than 180 degrees.

11. 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.

12. The capacitive imaging sensor of claim 8, wherein the second sensor electrode is disposed between the first sensor electrode and the third sensor electrode, and the second sensor electrode has a first protrusion that is disposed between the first sensor electrodes and the trace.

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

14. The capacitive imaging sensor of claim 1, wherein the first set of sensor electrodes further comprises a sixth sensor electrode that is configured to capacitively couple with the fourth sensor electrode.

15. The capacitive imaging sensor of claim 1, wherein either the first sensor electrode or the fourth sensor electrode at least partially enclose a region that has a conductive layer disposed therein that is coupled to a ground.

16. A touch screen, comprising:

a plurality of sensor electrodes disposed on a surface of a transparent substrate, the plurality of sensor electrodes comprising;

a first set of sensor electrodes comprising a first receiver electrode, a second receiver electrode and a third receiver electrode, and the first receiver electrode is electrically coupled to the third receiver electrode; and

a second set of sensor electrodes comprising a first transmitter electrode and a second transmitter electrode, wherein the first transmitter electrode is configured to capacitively couple with the first receiver electrode, and the second transmitter electrode is configured to capacitively couple with the third receiver electrode; and

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