Input device and method with pressure-sensitive layer

• US 9,383,881 B2
• Filed: 06/02/2010
• Issued: 07/05/2016
• Est. Priority Date: 06/03/2009
• Status: Active Grant

• Current Assignee: Synaptics Incorporated
• Original Assignee: Synaptics Incorporated
• Inventors: Day, Shawn P., Schediwy, Richard R.
• Primary Examiner(s): Vazquez, Arleen M
• Assistant Examiner(s): Andrews, Brent J
• Application Number:
  US12/792,578
• Publication Number:
  US 20100308844A1
• Time in Patent Office: 2,225 Days
• Field of Search: 324642-643, 324642-543, 324650-690, 345173-178, 204/193, 204/194, 204/400, 204/421, 204/424, 204/427, 734/88, 735/04
• US Class Current: 1/1
• 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 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes
• CPC Class Codes: G06F 3/0447 Position sensing using the local deformation of sensor cells
• CPC Class Codes: G06F 3/045 using resistive elements, e.g. a single continuous surface or two parallel surfaces put in contact

Abstract

Devices and methods are provided that facilitate improved input device performance. Specifically, the devices and methods facilitate input using a pressure-sensitive layer whose electrical admittivity changes in response to pressure applied to a touch surface. An input device is provided that comprises a plurality of sensor electrodes including a set of primary sensor electrodes and a set of secondary sensor electrodes. Each primary sensor electrode is electrically coupled to at least one secondary sensor electrode to form a set of electrical admittances. In one embodiment, the pressure-sensitive layer is located between the sensor electrodes and the touch surface, such that changes in the admittivity of the pressure-sensitive layer in response to pressure on the touch surface cause corresponding changes in the admittances between the primary and secondary sensor electrodes.

Claims

1. A pressure sensitive input device for sensing an input object in a sensing region, comprising:

a plurality of sensor electrodes comprising;

a set of primary sensor electrodes; and

a set of secondary sensor electrodes, each of the primary sensor electrodes being electrically coupled to and disposed at a fixed distance from at least one of the secondary sensor electrodes to form a set of measurable admittances between each primary sensor electrode and secondary sensor electrode, respectively;

a touch surface; and

a pressure-sensitive layer located between the touch surface and both the set of primary sensor electrodes and the set of secondary sensor electrodes, the pressure-sensitive layer configured to change at least one of the measurable admittances, without changing the fixed distance between each primary sensor electrode and each corresponding secondary sensor electrode, in response to pressure applied to the touch surface.

2. The input device of claim 1 further comprising a processing system coupled to the primary sensor electrodes and coupled to the secondary sensor electrodes and configured to determine measures of the admittances, the processing system further configured to determine positional information for the input object in the sensing region based upon the measures of the admittances.

3. The input device of claim 1 further comprising a processing system coupled to the primary sensor electrodes and coupled to the secondary sensor electrodes and configured to determine measures of the admittances, the processing system further configured to determine pressure information for the input object based upon a change in at least one of the measures.

4. The input device of claim 1 further comprising a processing system coupled to the primary sensor electrodes and coupled to the secondary sensor electrodes and configured to determine measures of the admittances, the processing system further configured to distinguish between at least two types of objects based upon a sign of a change in at least one of the measures.

5. The input device of claim 4 wherein the types of objects comprise conductive objects and nonconductive objects, wherein the processing system is further configured to distinguish between a conductive object and a nonconductive object based upon the sign of the change in at least one of the measures.

6. The input device of claim 1 wherein the pressure-sensitive layer comprises an insulating material.

7. The input device of claim 1 wherein the pressure-sensitive layer comprises a plurality of pressure-sensitive segments.

8. The input device of claim 1 wherein the set of admittances comprises a set of conductive admittances.

9. The input device of claim 1 wherein the set of admittances comprises a set of elastive admittances.

10. The input device of claim 1 wherein the pressure-sensitive layer is configured to change the admittances in response to pressure by changing at least one of a dielectric constant and thickness of the pressure-sensitive layer.

11. The input device of claim 1 wherein the set of primary sensor electrodes comprises at least two primary sensor electrodes and the set of secondary sensor electrodes comprises at least two secondary sensor electrodes.

12. A pressure sensitive input device for sensing an input object in a sensing region, comprising:

a plurality of sensor electrodes comprising;

a set of primary sensor electrodes;

a set of secondary sensor electrodes, each of the primary sensor electrodes electrically coupled to and disposed at a fixed distance from at least one of the secondary sensor electrodes to form a set of measurable elastive admittances between each primary sensor electrode and secondary sensor electrode, respectively; and

a pressure-sensitive layer proximate to at least a portion of the plurality of sensor electrodes, the pressure-sensitive layer located between a touch surface and both the set of primary sensor electrodes and the set of secondary sensor electrodes and configured to change at least one of the measurable elastive admittances, without changing the fixed distance between each primary sensor electrode and each corresponding secondary sensor electrode, in response to pressure applied to the pressure-sensitive layer.

13. The input device of claim 12 further comprising a processing system coupled to the sensor electrodes and configured to determine measures of the elastive admittances, the processing system further configured to determine positional information for the input object in the sensing region based upon the measures of the elastive admittances.

14. The input device of claim 12 further comprising a processing system coupled to the sensor electrodes and configured to determine measures of the elastive admittances, the processing system further configured to determine pressure information for the input object based upon a change in at least one of the measures.

15. The input device of claim 12 further comprising a processing system coupled to the sensor electrodes and configured to determine measures of the elastive admittances, the processing system further configured to distinguish between two types of input objects based upon a sign of a change in at least one of the measures.

16. The input device of claim 15 wherein the two types of objects comprise conductive objects and nonconductive objects, wherein the processing system is further configured to distinguish between a conductive object and a nonconductive object based upon the sign of a change in at least one of the measures.

17. The input device of claim 12 wherein the pressure-sensitive layer comprises a pressure-sensitive material and an insulating material.

18. The input device of claim 12 wherein the pressure-sensitive layer comprises a plurality of pressure-sensitive segments.

19. The input device of claim 12 wherein the pressure-sensitive layer is configured to change at least one of the elastive admittances in response to pressure by changing at least one of a dielectric constant and a thickness of the pressure-sensitive layer.

20. The input device of claim 12 wherein the set of primary sensor electrodes comprises at least two primary sensor electrodes and wherein the set of secondary sensor electrodes comprises at least two secondary sensor electrodes.

21. The input device of claim 12 wherein the pressure-sensitive layer proximate to the at least a portion of the plurality of sensor electrodes comprises the pressure-sensitive layer overlapping at least a portion of the plurality of sensor electrodes.

22. A method for determining user input comprising:

driving signals onto a set of primary sensor electrodes, wherein the set of primary sensor electrodes is a first part of a plurality of sensor electrodes;

receiving signals with a set of secondary sensor electrodes, wherein the set of secondary sensor electrodes is a second part of the plurality of sensor electrodes, wherein each of the primary sensor electrodes is electrically coupled to and disposed at a fixed distance from at least one of the secondary sensor electrodes to form a set of measurable admittances, and wherein a pressure-sensitive layer is located between a touch surface and both the set of primary sensor electrodes and the set of secondary sensor electrodes, the pressure-sensitive layer configured to change at least one of the admittances, without changing the fixed distance between each primary sensor electrode and each corresponding secondary sensor electrode, in response to pressure applied to the pressure-sensitive layer by an input object on the touch surface;

determining measures of the admittances from the signals received;

determining positional information for the input object on the touch surface from the measures; and

providing an output representative of the positional information.

23. The method of claim 22 further comprising the steps of:

determining pressure information for the input object on the touch surface based upon a magnitude of a change in at least one of the measures; and

providing an output representative of the pressure information.

24. The method of claim 22 further comprising the steps of:

distinguishing between at least two types of input objects based upon a sign of change in at least one of the measures to determine an object type; and

providing an output representative of the object type.

25. The method of claim 22 wherein the pressure-sensitive layer is configured to change the measures in response to pressure by changing conductivity in the pressure-sensitive layer.

26. The method of claim 22 wherein the pressure-sensitive layer is configured to change the measures in response to pressure by changing at least one of a dielectric constant and a thickness of the pressure-sensitive layer.

27. A method for determining user input on a device comprising:

driving signals onto a set of primary sensor electrodes, wherein the set of primary sensor electrodes is a first part of a plurality of sensor electrodes;

receiving signals with a set of secondary sensor electrodes, wherein the set of secondary sensor electrodes is a second part of the plurality of sensor electrodes, wherein each of the primary sensor electrodes is electrically coupled to and disposed at a fixed distance from at least one of the secondary sensor electrodes to form a set of elastive admittances, and wherein a pressure-sensitive layer is proximate the plurality of sensor electrodes, the pressure-sensitive layer located between a touch surface and both the set of primary sensor electrodes and the set of secondary sensor electrodes configured to change at least one of the elastive admittances, without changing the fixed distance between each primary sensor electrode and each corresponding secondary sensor electrode, in response to pressure applied to the pressure-sensitive layer by an input object;

determining measures of the elastive admittances from the signals received;

determining positional information for the input object in a sensing region from the measures; and

providing an output representative of the positional information.

28. The method of claim 27 further comprising the steps of:

determining pressure information for the input object based upon a magnitude of change in at least one of the measures; and

providing an output representative of the pressure information.

29. The method of claim 27 further comprising the steps of:

determining an object type for the input object based upon a sign of change in at least one of the measures; and

providing an output representative of the object type.

30. The method of claim 27 wherein the pressure-sensitive layer is configured to change at least one of the elastive admittances in response to pressure by changing at least one of a dielectric constant and a thickness of the pressure-sensitive layer.

31. A processing system for use with a pressure sensitive input device, the processing system configured to:

drive signals onto a set of primary sensor electrodes, wherein the set of primary sensor electrodes is a first part of a plurality of sensor electrodes;

receive signals with a set of secondary sensor electrodes, wherein the set of secondary sensor electrodes is a second part of the plurality of sensor electrodes, wherein each of the primary sensor electrodes is electrically coupled to and disposed at a fixed distance from at least one of the secondary sensor electrodes to form a set of admittances, and wherein a pressure-sensitive layer is located between a touch surface and both the set of primary sensor electrodes and the set of secondary sensor electrodes, the pressure-sensitive layer configured to change at least one of the admittances, without changing the fixed distance between each primary sensor electrode and each corresponding secondary sensor electrode, in response to pressure applied to the pressure-sensitive layer by an input object on the touch surface;

determine measures of the admittances from the signals received;

determine positional information for the input object on the touch surface from the measures; and

provide an output representative of the positional information.

32. The processing system of claim 31 further configured to:

determine pressure information for the input object on the touch surface based upon a magnitude of a change in at least one of the measures; and

provide an output representative of the pressure information.

33. The processing system of claim 31 further configured to:

distinguish between at least two types of input objects based upon a sign of change in at least one of the measures to determine an object type; and

provide an output representative of the object type.

34. A processing system for use with a pressure sensitive input device, the processing system configured to:

drive signals onto a set of primary sensor electrodes, wherein the set of primary sensor electrodes is a first part of a plurality of sensor electrodes;

receive signals with a set of secondary sensor electrodes, wherein the set of secondary sensor electrodes is a second part of the plurality of sensor electrodes, wherein each of the primary sensor electrodes is electrically coupled to and disposed at a fixed distance from at least one of the secondary sensor electrodes to form a set of elastive admittances, and wherein a pressure-sensitive layer is proximate the plurality of sensor electrodes, the pressure-sensitive layer located between a touch surface and both the set of primary sensor electrodes and the set of secondary sensor electrodes and configured to change at least one of the elastive admittances, without changing the fixed distance between each primary sensor electrode and each corresponding secondary sensor electrode, in response to pressure applied to the pressure-sensitive layer by an input object;

determine measures of the elastive admittances from the signals received;

determine positional information for the input object in a sensing region from the measures; and

provide an output representative of the positional information.

35. The processing system of claim 34 further configured to:

determine pressure information for the input object based upon a magnitude of change in at least one of the measures; and

provide an output representative of the pressure information.

36. The processing system of claim 34 further configured to:

determine an object type for the input object based upon a sign of change in at least one of the measures; and

provide an output representative of the object type.

37. A pressure sensitive input device for sensing an input object in a sensing region, comprising:

a touch surface;

a primary sensor electrode disposed at a fixed distance from a secondary sensor electrode and forming a variable capacitance therebetween; and

a pressure-sensitive layer located between the touch surface and both the primary sensor electrode and the secondary sensor electrode, the pressure-sensitive layer configured to change the variable capacitance, without changing the fixed distance between primary sensor electrode and secondary sensor electrode, in response to pressure applied by the input object to the touch surface.