Electronic device having a piezoelectric body for friction haptics

• US 10,775,890 B2
• Filed: 09/27/2017
• Issued: 09/15/2020
• Est. Priority Date: 09/27/2017
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Wen, Xiaonan, Pedder, James E.
• Primary Examiner(s): Dicke, Chad M
• Application Number:
  US15/717,682
• Publication Number:
  US 20190094968A1
• Time in Patent Office: 1,084 Days
• CPC Class Codes: G06F 2203/04103 Manufacturing, i.e. details related to manufacturing processes specially suited for touch sensitive devices
• CPC Class Codes: G06F 2203/04105 Pressure sensors for measuring the pressure or force exerted on the touch surface without providing the touch position
• CPC Class Codes: G06F 3/016 Input arrangements with force or tactile feedback as computer generated output to the user
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/0416 Control or interface arrangements specially adapted for digitisers
• CPC Class Codes: G06F 3/04166 Details of scanning methods, e.g. sampling time, grouping of sub areas or time sharing with display driving Synchronisation with the driving of the display or the backlighting unit to avoid interferences generated internally G06F3/04184
• CPC Class Codes: G06F 3/044 by capacitive means
• CPC Class Codes: G06F 3/0443 using a single layer of sensing electrodes
• 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 3/147 using display panels
• CPC Class Codes: G06V 40/1306 non-optical, e.g. ultrasonic or capacitive sensing

Abstract

An electronic device is disclosed which includes a conductive layer for providing haptic feedback at an input surface of the electronic device. The conductive layer includes conductive particles within an organic compound, such as an epoxy. When the conductive layer is activated it may provide frictional or other tactile feedback at the input surface.

Claims

1. An electronic device, comprising:

a housing; and

a cover assembly coupled to the housing and comprising;

a cover layer;

an electrostatic output layer below the cover layer configured to receive a voltage to capacitively couple to a user touching the cover layer, the electrostatic output layer comprising;

an epoxy layer coupled to the cover layer;

an array of nonconductive particles disposed within the epoxy layer;

an array of conductive particles dispersed to a predetermined density within the epoxy layer and among the array of nonconductive particles; and

a piezoelectric body below the cover layer and defining an upper surface and a lower surface;

a first electrode group disposed on the upper surface; and

a second electrode group disposed on the lower surface and comprising;

a touch sense electrode coupled to a capacitive touch sensor; and

a haptic drive electrode configured to apply a voltage across the piezoelectric body to generate haptic feedback through the cover assembly.

2. The electronic device of claim 1, further comprising processing circuitry coupled to the first and second electrode groups.

3. The electronic device of claim 2, wherein the processing circuitry is configured to apply the voltage across the piezoelectric body in response to a touch.

4. The electronic device of claim 1, wherein the touch sense electrode is disposed adjacent to the haptic drive electrode.

5. The electronic device of claim 1, wherein:

the touch sense electrode is a member of a set of touch sense electrodes; and

the haptic drive electrode is a member of a set of haptic drive electrodes.

6. The electronic device of claim 5, wherein the set of haptic drive electrodes are interstitially disposed between the set of touch sense electrodes.

7. The electronic device of claim 1, wherein the second electrode group is arranged as a set of columns and the first electrode group is arranged as a set of rows, perpendicular to the set of columns.

8. The electronic device of claim 1, wherein the touch sense electrode has a first trace width and the haptic drive electrode has a second trace width.

9. The electronic device of claim 8, wherein the second trace width is greater than the second trace width.

10. The electronic device of claim 1, wherein the first electrode group and the second electrode group are optically transparent.

11. An electronic device, comprising:

a transparent cover;

an electrostatic output layer below the transparent cover configured to receive a voltage to capacitively couple to a user touching the transparent cover, the electrostatic output layer comprising;

an epoxy layer coupled to and extending across the transparent cover; and

an array of conductive particles disposed at a predetermined density within a defined region of the epoxy layer;

a display below the transparent cover defining an active display area below the epoxy layer of the electrostatic output layer, the defined region within the active display area;

a user input sensor positioned below the transparent cover and above the display, the predetermined density selected to not interfere with operation of the user input sensor;

a stiffener layer below the user input sensor;

a piezoelectric body below the user input sensor and defining an upper surface and a lower surface;

a haptic reference electrode group disposed on the upper surface; and

a haptic drive electrode group disposed on the lower surface and configured to apply a voltage across the piezoelectric body to generate haptic feedback through the user input sensor and the transparent cover.

12. The electronic device of claim 11, wherein the display is disposed below the piezoelectric body.

13. The electronic device of claim 11, wherein the user input sensor is a force input sensor.

14. The electronic device of claim 11, wherein the user input sensor is a touch input sensor.

15. The electronic device of claim 11, wherein the display is disposed below the piezoelectric body.

16. The electronic device of claim 15, wherein the stiffener layer is positioned below the display.

17. A cover assembly for an electronic device, comprising:

a transparent cover layer;

an electrostatic output layer below the transparent cover layer configured to receive a voltage to capacitively couple to a user touching the transparent cover layer, the electrostatic output layer comprising;

an epoxy layer coupled to the transparent cover layer;

a nonconductive particle array disposed at a first density within the epoxy layer; and

a conductive particle array disposed at a second density within the epoxy layer, the conductive particle array dispersed among the nonconductive particle array;

a piezoelectric body below the transparent cover layer and the electrostatic output layer and defining an upper surface and a lower surface;

a first electrode group disposed on the upper surface; and

a touch sense electrode group disposed on the lower surface and coupled to a capacitive touch sensor; and

a haptic drive electrode group disposed on the lower surface and arrange interstitially with the touch sense electrode group, the haptic drive electrode group configured to apply a voltage across the piezoelectric body to generate haptic feedback through the cover assembly.

18. The cover assembly of claim 17, further comprising a display positioned below the piezoelectric body.

19. The cover assembly of claim 17, further comprising a stiffener layer positioned above the piezoelectric body.

20. The cover assembly of claim 17, wherein the first electrode group is arranged perpendicular to the touch sense electrode group and the haptic drive electrode group.

21. The cover assembly of claim 17, wherein the first density is different from the second density.

22. The cover assembly of claim 21, wherein the first density is greater than the second density.

23. The cover assembly of claim 21, wherein the conductive particle array is disposed at the second density within a defined region of the nonconductive particle array.