Force determination employing sheet sensor

• US 10,739,899 B2
• Filed: 08/12/2019
• Issued: 08/11/2020
• Est. Priority Date: 02/12/2014
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Filiz, Sinan, Grunthaner, Martin P., Smith, John Stephen, Ogata, Charley T., Sauer, Christian M., Choi, Shin John, Butler, Christopher J., Martisauskas, Steven J.
• Primary Examiner(s): Lee, Benjamin C
• Assistant Examiner(s): Neupane, Krishna P.
• Application Number:
  US16/538,724
• Publication Number:
  US 20190361560A1
• Time in Patent Office: 365 Days
• Field of Search: None
• 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 2203/04106 Multi-sensing digitiser, i.e. digitiser using at least two different sensing technologies simultaneously or alternatively, e.g. for detecting pen and finger, for saving power or for improving position detection
• 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 3/0447 Position sensing using the local deformation of sensor cells

Abstract

A device configured to sense a touch on a surface of the device. The device includes a cover and a force-sensing structure disposed below the cover. The force-sensing structure may be positioned below a display and used in combination with other force-sensing elements to estimate the force of a touch on the cover of a device.

Claims

1. An electronic device comprising:

a housing defining a bezel around an opening;

a cover disposed over the opening;

a gasket disposed in a gap between the cover and the bezel;

a display positioned below the cover;

a force-sensing structure disposed below the display and entirely separated from the display by a compliant layer including an air gap, wherein the force-sensing structure comprises;

a first capacitive plate;

a second capacitive plate; and

a compressible element disposed between the first capacitive plate and the second capacitive plate;

a plate affixed to the housing and supporting the force-sensing structure; and

sensing circuitry that is operatively coupled to the force-sensing structure and configured to estimate a force of a touch on the cover in response to a change in capacitance between the first capacitive plate and the second capacitive plate;

wherein,

the force of the touch is not sensed by the force-sensing structure until the force closes a portion of the air gap and the display begins to compress the force-sensing structure.

2. The electronic device of claim 1, wherein the compliant layer comprises a compressible foam.

3. The electronic device of claim 1, wherein the force-sensing structure is separated from the display by a compliant layer comprising an array of compliant pillars and an optically transparent fluid.

4. The electronic device of claim 1, further comprising:

an oleophobic coating disposed on at least one surface defining at least a portion of the gap.

5. The electronic device of claim 1, wherein one of the first and second capacitive plates is a drive plate, and the other of the first and second capacitive plates is a sense plate.

6. An electronic device comprising:

a housing having an interior;

a cover disposed within an opening of the housing;

a display disposed below the cover;

a gasket disposed between the cover and the housing;

a force-sensing structure disposed below the display and entirely separated from the display by an air gap, wherein the force-sensing structure comprises;

a first capacitive plate;

a second capacitive plate; and

a compressible element disposed between the first capacitive plate and the second capacitive plate; and

sensing circuitry that is operatively coupled to the force-sensing structure and configured to estimate a force of a touch on the cover in response to a change in capacitance between the first capacitive plate and the second capacitive plate;

wherein,

the force of the touch is not sensed by the force-sensing structure until the force closes a portion of the air gap and the display begins to compress the force-sensing structure.

7. The electronic device of claim 6, further comprising a plate fixed relative to the housing and supporting the force-sensing structure.

8. The electronic device of claim 6, wherein:

the air gap is configured to at least partially collapse in response to a force of a touch that exceeds a first threshold; and

the first threshold is less than a second threshold that corresponds to a maximum force that can be detected by the gasket.

9. The electronic device of claim 6, wherein:

the air gap is configured to at least partially close in response to a force of a touch that exceeds a first threshold, and

the first threshold is less than a second threshold that corresponds to a maximum force that can be detected by the gasket.

10. An electronic device comprising:

a housing defining a bezel around an opening;

a cover disposed within the opening;

a compliant environmental gasket disposed in a lateral gap between the cover and the bezel;

a display positioned below the cover;

a sheet sensor disposed below the display and entirely separated from the display by an air gap, wherein the sheet sensor comprises;

a first capacitive plate;

a second capacitive plate; and

a compressible element disposed between the first capacitive plate and the second capacitive plate;

a plate affixed to the housing and supporting the sheet sensor; and

sensing circuitry that is operatively coupled to the sheet sensor and configured to estimate a force of a touch on the cover in response to a change in capacitance between the first capacitive plate and the second capacitive plate;

wherein,

the force of the touch is not sensed by the sheet sensor until the force closes a portion of the air gap and the display begins to compress the sheet sensor.