Systems and methods for detecting a press on a touch-sensitive surface

• US 9,454,270 B2
• Filed: 04/10/2012
• Issued: 09/27/2016
• Est. Priority Date: 09/19/2008
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Marsden, Randal J., Hole, Steve, Closson, Daniel
• Primary Examiner(s): Wang, Quan-Zhen
• Assistant Examiner(s): Zheng, Xuemei
• Application Number:
  US13/442,855
• Publication Number:
  US 20130093715A1
• Time in Patent Office: 1,631 Days
• Field of Search: 345/168
• US Class Current: 1/1
• CPC Class Codes: G06F 3/023 Arrangements for converting discrete items of information into a coded form, e.g. arrangements for interpreting keyboard generated codes as alphanumeric codes, operand codes or instruction codes
• CPC Class Codes: G06F 3/0231 Cordless keyboards
• CPC Class Codes: H03K 17/962 Capacitive touch switches
• CPC Class Codes: H03K 2217/94052 with evaluation of actuation pattern or sequence, e.g. tapping
• CPC Class Codes: H03K 2217/960775 Emitter-receiver or "fringe" type detection, i.e. one or more field emitting electrodes and corresponding one or more receiving electrodes

Abstract

Systems and methods that allow the user to rest their fingers on a touch-sensitive surface and make selections on that surface with a pressing action. Touch capacitance sensors that typically provide X and Y location data associated with a user'"'"'s touch are also used to discern finger pressure in the Z direction. This allows the user to make an actuation on the touch screen by simply pressing harder at a location where they may already be resting their finger(s).

Claims

1. A system comprising:

a touch sensitive surface comprising a plurality of touch capacitive sensors associated with actionable locations on the touch sensitive surface, wherein each touch capacitive sensor of the plurality of touch capacitive sensors is associated with a respective key of a plurality of keys of a virtual keyboard;

a processor configured to;

determine that a user interaction is a selection event when one of one or more signals received from one or more of the plurality of touch capacitive sensors has a leading rising edge with a rate-of-change that exceeds a first rate-of-change threshold followed within a predefined amount of time by a falling edge decreasing in value at a rate-of-change greater than a second rate-of-change threshold;

determine that a user interaction of resting multiple fingers on the touch sensitive surface is a resting action when multiple signals received from one or more of the plurality of touch capacitive sensors are between a first threshold value and a second threshold value, and the rate-of-change of the leading rising edge of the multiple signals is less than the first rate-of-change threshold and the multiple signals are above the first threshold value, wherein the resting action is not actionable; and

determine that a user interaction with the touch sensitive surface is a press action on a key of the plurality of keys of the virtual keyboard when one or more signals received from one or more of the plurality of touch capacitive sensors are above the second threshold value.

2. The system of claim 1, wherein the first and second threshold values are predefined.

3. The system of claim 1, wherein the first and second threshold values are variable based on individual touch characteristics of each user.

4. The system of claim 1, wherein the processor is further configured to assert an activation after a determined resting action for a particular user interaction is followed by a determined press action on an actionable location.

5. The system of claim 1, wherein the processor is further configured to

determine a press and hold event when a determined resting action for a particular user interaction is followed by a determined press action that is sustained for longer than a predefined key repeat time.

6. The system of claim 1, wherein the first and second rate-of-change thresholds are the same.

7. The system of claim 1, wherein the processor is configured to determine that the user action is a resting action when amplitudes of the multiple signals are greater than at least the first threshold value.

8. The system of claim 1, wherein the processor is further configured to determine that the user interaction with the touch sensitive surface is the press action when the rate-of-change of the leading rising edge of the one or more signals is less than the first rate-of-change threshold and the one or more signals are above the second threshold value.

9. The system of claim 1, further comprising an output device configured to present a response corresponding to the press action.

10. The system of claim 1, wherein the processor is further configured to:

determine that a user interaction with the touch sensitive surface is a tap action on the key of the plurality of keys of the virtual keyboard when a rising slope of one or more signals received from one or more of the plurality of touch capacitive sensors is steep in accordance with predetermined criterion.

11. A system comprising:

a touch sensitive surface comprising a plurality of touch capacitive sensors associated with actionable locations on the touch sensitive surface, wherein each touch capacitive sensor of the plurality of touch capacitive sensors is associated with a respective key of a plurality of keys of a virtual keyboard; and

a processor in signal communication with the touch sensitive surface, the processor configured to;

determine that a user interaction of resting multiple fingers on the touch sensitive surface is a resting action when multiple signals received from one or more of the plurality of touch capacitive sensors are between a first threshold value and a second threshold value, wherein the resting action is not actionable;

upon determining that the user interaction is the resting action, determine a peak of one of the multiple signals and determine a difference in amplitude of the multiple signals associated with the resting action and the determined peak,

wherein if the determined difference is greater than a first predefined delta threshold, determine that a user interaction with the touch sensitive surface is a press action on a key of the plurality of keys of the virtual keyboard;

upon determining that the user interaction is the press action, determine a trough of one of the multiple signals, and determine a difference in amplitude of the multiple signals associated with the press action and the determined trough,

wherein if the multiple signals are determined to be at or below the first threshold value, determine that a user interaction with the touch sensitive surface is a rest and release action; and

wherein if the trough and the peak have a difference that is greater than a second predefined delta threshold, determine that a user interaction with the touch sensitive surface is a press and release action on the key of the plurality of keys of the virtual keyboard.

12. The system of claim 11, wherein the first and second predefined delta thresholds are the same.

13. The system of claim 11, further comprising an output device configured to present a response corresponding to the press action.

14. A system comprising:

a touch sensitive surface comprising a plurality of touch capacitive sensors associated with actionable locations on the surface, wherein each touch capacitive sensor of the plurality of touch capacitive sensors is associated with a respective key of a plurality of keys of a virtual keyboard; and

a processor configured to;

determine that a user interaction of resting multiple fingers on the touch sensitive surface is a resting action when multiple signals received from one or more of the plurality of touch capacitive sensors are between a first threshold value and a second threshold value, wherein the resting action is not actionable;

determine that a user interaction with the touch sensitive surface is a press action on a key of the plurality of keys of the virtual keyboard when a rate-of-change of a leading rising edge of a signal of one or more signals received from one or more of the plurality of touch capacitive sensors is less than a first rate-of-change threshold and the one or more signals are above a second threshold value;

after determination of the resting action, determine a peak of one of the multiple signals and determine a difference in amplitude of the multiple signals associated with the resting action and the determined peak;

if the determined difference is greater than a first predefined delta threshold, determine that a user interaction with the touch sensitive surface is a press action on the key of the plurality of keys of the virtual keyboard;

after determination of the press action, determine that a user interaction with the touch sensitive surface is at least one of;

a rest and press release action on the key of the plurality of keys of the virtual keyboard, if the multiple signals are determined to be at or below the first threshold value;

or

a press release action on the key of the plurality of keys of the virtual keyboard, wherein the processor determines an amplitude of a trough of one of the multiple signals and determines the user interaction is the press release action if the trough amplitude and the determined peak have a difference that is greater than a second predefined delta threshold.

15. The system of claim 14, wherein the first and second predefined delta thresholds are the same.

16. The system of claim 14, further comprising an output device configured to present a response corresponding to the press action.

17. A system comprising:

a touch sensitive surface comprising a plurality of touch capacitive sensors associated with actionable locations on the touch sensitive surface, wherein each touch capacitive sensor of the plurality of touch capacitive sensors is associated with a respective key of a plurality of keys of a virtual keyboard;

a processor configured to;

determine that a user interaction of resting multiple fingers on the touch sensitive surface is a resting action when;

(i) multiple signals received from one or more of the plurality of touch capacitive sensors are between a first threshold value and a second threshold value, wherein the resting action is not actionable, and (ii) amplitudes of the multiple signals stabilize when the amplitudes of the multiple signals level off and remain relatively constant for a predetermined amount of time; and

determine that a user interaction with the touch sensitive surface is a press action on a key of the plurality of keys of the virtual keyboard when one or more signals received from one or more of the plurality of touch capacitive sensors are above the second threshold value.