FORCE ENHANCED INPUT DEVICE WITH SHIELDED ELECTRODES

• US 20160291719A1
• Filed: 03/31/2015
• Published: 10/06/2016
• Est. Priority Date: 03/31/2015
• Status: Active Grant

• Current Assignee: Synaptics Incorporated
• Original Assignee: Synaptics Incorporated
• Inventors: Chiu, Pei-Che, Lee, Wei-Lung
• Granted Patent: US 9,785,296 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 2203/04108 Touchless 2D- digitiser, i.e. digitiser detecting the X/Y position of the input means, finger or stylus, also when it does not touch, but is proximate to the digitiser's interaction surface without distance measurement in the Z direction
• CPC Class Codes: G06F 3/04144 using an array of force sensing means position sensing using the local deformation of sensor cells G06F3/0447
• 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 3/0447 Position sensing using the local deformation of sensor cells

Abstract

An input device includes an input surface and a first substrate mechanically coupled to the input surface. The first substrate includes a first plurality of sensor electrodes configured to detect an input force applied by an input object to the input surface. The input device further includes a conductive material disposed between the input surface and the first plurality of sensor electrodes. The conductive material shields the first plurality of sensor electrodes from effects of the input object in a sensing region of the input device. The input device further includes a second substrate mechanically coupled to the first substrate. The second substrate includes a second plurality of sensor electrodes configured to detect a location of an input object at the input surface.

Claims

1. An input device, comprising:

an input surface;

a first substrate mechanically coupled to the input surface, the first substrate comprising a first plurality of sensor electrodes configured to detect an input force applied by an input object to the input surface;

a conductive material disposed between the input surface and the first plurality of sensor electrodes, wherein the conductive material shields the first plurality of sensor electrodes from effects of the input object in a sensing region of the input device; and

a second substrate mechanically coupled to the first substrate, the second substrate comprising a second plurality of sensor electrodes configured to detect a location of the input object at the input surface.

2. The input device of claim 1,

wherein the second plurality of sensor electrodes comprises a first subset of sensor electrodes and a second subset of sensor electrodes, and

wherein the first subset and the second subset of sensor electrodes are configured to capacitively couple and form a plurality of areas of variable capacitance.

3. The input device of claim 1,

wherein the conductive material is disposed on the first substrate,

wherein the second plurality of sensor electrodes comprises a first subset of sensor electrodes and a second subset of sensor electrodes,

wherein the first subset of sensor electrodes are configured to receive a resulting signal comprising effects of input objects in the sensing region, and

wherein the conductive material is configured to be maintained at a substantially constant electric potential while the sensing signal is transmitted through the first subset of sensor electrodes.

4. The input device of claim 3,

wherein the first plurality of electrodes and the second subset of sensor electrodes are substantially aligned in a pattern along the first substrate and the second substrate.

5. The input device of claim 3,

wherein the second subset of sensor electrodes is disposed at a horizontal offset in the second substrate from the first plurality of sensor electrodes.

6. The input device of claim 1,

wherein the conductive material overlaps the first plurality of electrodes.

7. The input device of claim 1, further comprising:

a compliant component disposed between the first substrate and the second substrate,

wherein, in response to the input force being applied to the input surface, the first substrate is configured to deflect the first plurality of sensor electrodes toward the second substrate, and

wherein the compliant component, the first substrate and the input surface are configured to locally deform in response to the input force.

8. The input device of claim 7,

wherein the compliant component comprises a substantially homogenous foam medium.

9. The input device of claim 7,

wherein the compliant component comprises an array of raised regions, and

wherein the first plurality of electrodes are disposed on the array of raised regions.

10. The input device of claim 1,

wherein the first substrate comprises polyethylene terephthalate (PET), and

wherein the second substrate comprises a printed circuit board.

11. The input device of claim 1,

further comprising a processing system communicatively coupled to the first plurality and second plurality of sensor electrodes,

wherein the second plurality of sensor electrodes comprises a first subset of sensor electrodes and a second subset of sensor electrodes, the processing system comprising:

a determination module configured for processing a first resulting signal and a second resulting signal,

wherein the first resulting signal is based on a change in a first variable capacitance formed between the first subset of sensor electrodes and the first plurality of sensor electrodes, and

wherein the second resulting signal is based on a change in a second variable capacitance formed between the first subset and the second subset of sensor electrodes.

12. A processing system for an input device comprising an input surface, a first substrate comprising a first plurality of sensor electrodes, and a second substrate comprising a second plurality of sensor electrodes, the processing system comprising:

a sensor module configured to;

receive a first resulting signal associated with the first plurality of sensor electrodes; and

receive a second resulting signal associated with the second plurality of sensor electrodes, the second plurality of sensor electrodes comprising a first subset of sensor electrodes and a second subset of sensor electrodes; and

a determination module configured to;

determine force information applied by an input object to the input surface based on the first resulting signal, the first resulting signal based on a change in a first variable capacitance formed between the first subset of sensor electrodes of the second plurality of sensor electrodes and the first plurality of sensor electrodes; and

determine positional information of the input object in a sensing region of the input device based on a second resulting signal, the second resulting signal based on a change in a second variable capacitance formed between the first subset and the second subset of sensor electrodes,

wherein the input device further comprises a conductive material disposed between the input surface and the first plurality of sensor electrodes.

13. The processing system of claim 12,

wherein the first variable capacitance changes in response to a force applied to the input surface and deflection of the first plurality of sensor electrodes towards the first subset of sensor electrodes of the second plurality of sensor electrodes.

14. The processing system of claim 12, wherein the input device further comprises:

a compliant component disposed between the first substrate and the second substrate and configured to locally deform in response to a force applied to the input surface.

15. The processing system of claim 14,

wherein the compliant component comprises a substantially homogenous foam medium.

16. The processing system of claim 14,

wherein the compliant component comprises an array of raised regions, and

wherein the first plurality of sensor electrodes are disposed on the array of raised regions.

17. A method for manufacturing an input device, comprising:

providing a first substrate, the first substrate comprising a first plurality of sensor electrodes;

disposing a second substrate on or above the first substrate, the second substrate comprising a second plurality of sensor electrodes and a conductive material; and

disposing an input surface on or above the second substrate,

wherein the first plurality of sensor electrodes are configured to detect a location of an input object at the input surface,

wherein the second plurality of sensor electrodes are configured to detect an input force applied by the input object to the input surface, and

wherein the conductive material shields the second plurality of sensor electrodes from effects of the input object on or above the input surface.

18. The method of claim 17, further comprising:

communicatively coupling a processing system to the first plurality of sensor electrodes and the second plurality of sensor electrodes, the processing system comprising a determination module configured for processing a first resulting signal and a second resulting signal,

wherein the first plurality of sensor electrodes comprises a first subset of sensor electrodes and a second subset of sensor electrodes,

where the first resulting signal is based on a change in a first variable capacitance formed between the first subset of sensor electrodes and the second plurality of sensor electrodes, and

wherein the second resulting signal is based on a change in a second variable capacitance formed between the first subset and the second subset of sensor electrodes.

19. The method of claim 17, further comprising:

disposing a compliant component between the first substrate and the second substrate, wherein the compliant component is configured to locally deform in response to the input force applied to the input surface.

20. The method of claim 19, further comprising:

wherein the compliant component comprises a substantially homogenous foam medium.