Force-Sensitive Fingerprint Sensing Input

• US 20160033342A1
• Filed: 03/15/2013
• Published: 02/04/2016
• Est. Priority Date: 03/15/2013
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Lyon, Benjamin B., Setlak, Dale, Wittenberg, Michael B., Choi, Shin John
• Granted Patent: US 10,209,148 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G01L 1/142 using capacitors
• CPC Class Codes: H03K 17/975 using a capacitive movable element
• CPC Class Codes: H03K 2217/960755 Constructional details of capacitive touch and proximity switches
• CPC Class Codes: H03K 2217/960765 Details of shielding arrangements

Abstract

An object can depress an input device, such as, for example, a function button in an electronic device. A resistive element having a mechanically resistive force can be disposed to resist the depression or movement of the input device. One or more electrodes can be disposed to provide a measure of capacitance based on the depression of the input device. A shield can be disposed to reduce the parasitic capacitance between the one or more electrodes and the object. The electronic device can include a fingerprint sensor operably connected to at least one of the one or more electrodes.

Claims

1. An electronic device, comprising:

an input device depressible in response to an object;

a resistive element having a mechanically resistive force, the resistive element disposed to resist depression of the input device; and

one or more electrodes disposed to provide a measure of capacitance based on a depression of the input device.

2. The electronic device as in claim 1, wherein the input device comprises a function button.

3. The electronic device as in claim 1, further comprising a shield that reduces parasitic capacitance between the one or more electrodes and the object.

4. The electronic device as in claim 1, wherein the resistive element comprises an elastomeric substance disposed to resist depression of the input device.

5. The electronic device as in claim 1, further comprising a fingerprint sensor operably connected to at least one electrode.

6. The electronic device as in claim 2, wherein the function button comprises a stack of layers, the stack of layers including a lens disposed over an insulator.

7. The electronic device as in claim 6, wherein a shield is included in the stack of layers and is disposed between the lens and the insulator.

8. The electronic device as in claim 7, wherein the one or more electrodes include a first electrode disposed on a first side of the resistive element and a second electrode disposed on a second side of the resistive element, wherein a capacitance between the first electrode and the second electrode changes based on the depression of the function button.

9. The electronic device as in claim 1, wherein the resistive element has a resistance that changes under pressure.

10. The electronic device as in claim 1, wherein the resistive element includes a piezoelectric material.

11. The electronic device as in claim 1, wherein the resistive element is disposed in a ring about a fingerprint sensor.

12. The electronic device as in claim 11, wherein at least one electrode comprises electrode segments that are disposed in different directions, and wherein the electronic device can measure a direction of an applied force.

13. The electronic device as in claim 3, wherein the one or more electrodes include a first electrode disposed on a first side of the resistive element and a second electrode disposed on a second side of the resistive element, wherein a capacitance between the first electrode and the second electrode changes based on the depression of the input device,

and wherein the shield includes an electrode disposed between the one or more electrodes.

14. The electronic device as in claim 1, wherein

a spacer is disposed between the first electrode and a trim;

and

the second electrode is separated from the trim by an insulator.

15. The electronic device as in claim 1, wherein the one or more electrodes include a first electrode disposed on a first side of an insulator and a second electrode disposed on a second side of the insulator, the first electrode connected to a trim and the second electrode connected to ground.

16. The electronic device as in claim 1, wherein

the one or more electrodes includes a first electrode and a second electrode, the first electrode and the second electrode being disposed substantially perpendicular to a surface of the input device,

and wherein the first electrode and the second electrode include tines disposed substantially parallel to the surface of the input device, the tines of the first electrode interlaced with the tines of the second electrode.

17. The electronic device as in claim 1, wherein

the one or more electrodes includes a first electrode that includes a plurality of plates disposed substantially in parallel to a surface of the input device and a second electrode that includes a plurality of plates disposed substantially in parallel to a surface of the input device, the plates of the first electrode interlaced with the plates of the second electrode,

and wherein depression of the input device adjusts a distance between the first plurality of plates and the second plurality of plates.

18. The electronic device as in claim 1, wherein the one or more electrodes includes a first trim portion disposed below the input device and on a first side of an insulator, and a second trim portion disposed on a second side of the resistive element.

19. The electronic device as in claim 18, wherein the first trim portion is separated from the input device by an insulator.

20. The electronic device as in claim 18, wherein the first trim portion is connected to ground.

21. The electronic device as in claim 18, wherein the second trim portion is connected to the one or more electrodes.

31. The method as in claim 19, further comprising resisting depression of the input device by a resistive element having a mechanically resistive force.

22. An electronic device including

an input device depressible in response to a finger;

a force sensor responsive to depression of the function button; and

a fingerprint sensor responsive to contact or near-contact by the finger.

23. The electronic device as in claim 22, wherein the input device comprises a function button.

24. The electronic device as in claim 22, further comprising a resistive element having a mechanically resistive force, the resistive element disposed to resist depression of the input device.

25. A method for determining an amount of an applied force, comprising

resisting depression of an input device by a resistive element having a mechanically resistive force;

measuring a capacitance based on a depression of the input device; and

shielding the measured capacitance from parasitic capacitance from an object in proximity or in contact with the input device.

26. The method as in claim 25, wherein resisting depression of an input device by a resistive element having a mechanically resistive force comprises resisting depression of a function button by a resistive element having a mechanically resistive force.

27. The method as in claim 25, wherein the object comprises a user'"'"'s finger, the method including obtaining a fingerprint image of at least a portion of the user'"'"'s finger in response to the proximity or contact of the user'"'"'s finger to the input device.

28. The method as in claim 25, including determining a direction of the applied force on the input device.

29. A method for operating an electronic device, comprising

receiving an applied force measurement based on a depression of an input device;

and

receiving a fingerprint image based on the depression of the input device.

30. The method as in claim 29, further comprising receiving a direction measurement of the applied force on the input device.

32. An electronic device, comprising:

an input device depressible in response to an applied force;

a resistive element having a mechanically resistive force, the resistive element disposed to resist depression of the input device;

a first electrode including a first plurality of tines or plates; and

a second electrode including a second plurality of tines or plates, wherein the first plurality of tines or plates are interlaced with the second plurality of tines or plates to provide a measure of capacitance based on a depression of the input device.

33. An electronic device, comprising:

an input device depressible in response to an applied force;

a resistive element having a mechanically resistive force, the resistive element disposed to resist depression of the input device;

a drive electrode; and

a sense electrode disposed below the drive electrode, wherein the drive electrode and the sense electrode provide a measure of capacitance based on a depression of the input device.