Unintentional touch rejection

• US 20070152976A1
• Filed: 12/30/2005
• Published: 07/05/2007
• Est. Priority Date: 12/30/2005
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Scott, Bryan, Townsend, Reed, Dodge, Steven, Kolmykov-Zotov, Alexander
• Granted Patent: US 8,018,440 B2
• Time in Patent Office: Days
• US Class Current: 345/173
• CPC Class Codes: G06F 2203/0381 Multimodal input, i.e. interface arrangements enabling the user to issue commands by simultaneous use of input devices of different nature, e.g. voice plus gesture on digitizer
• CPC Class Codes: G06F 2203/04104 Multi-touch detection in digitiser, i.e. details about the simultaneous detection of a plurality of touching locations, e.g. multiple fingers or pen and finger
• 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 3/03545 Pens or stylus
• CPC Class Codes: G06F 3/038 Control and interface arrangements therefor, e.g. drivers or device-embedded control circuitry
• CPC Class Codes: G06F 3/041 Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
• CPC Class Codes: G06F 3/0414 using force sensing means to determine a position
• CPC Class Codes: G06F 3/0416 Control or interface arrangements specially adapted for digitisers
• CPC Class Codes: G06F 3/0418 for error correction or compensation, e.g. based on parallax, calibration or alignment
• CPC Class Codes: G06F 3/04186 Touch location disambiguation
• CPC Class Codes: G06F 3/0488 using a touch-screen or digitiser, e.g. input of commands through traced gestures

Abstract

A method for rejecting an unintentional palm touch is disclosed. In at least some embodiments, a touch is detected by a touch-sensitive surface associated with a display. Characteristics of the touch may be used to generate a set of parameters related to the touch. In an embodiment, firmware is used to determine a reliability value for the touch. The reliability value and the location of the touch is provided to a software module. The software module uses the reliability value and an activity context to determine a confidence level of the touch. In an embodiment, the confidence level may include an evaluation of changes in the reliability value over time. If the confidence level for the touch is too low, it may be rejected.

Claims

1. In a computer system having a graphical user interface including a touch-sensitive device, a method of distinguishing between intentional and inadvertent contact on the touch-sensitive device, the method comprising:

(a) receiving a touch on the touch-sensitive device;

(b) determining whether the touch exceeds a confidence level; and

(c) if the touch exceeds the confidence level, communicating an associated input to an application.

2. The method of claim 1, wherein the receiving in (a) comprises:

(i) detecting the touch of a user'"'"'s hand on a first area of the touch-sensitive surface; and

(ii) generating a set of parameters related to the touch.

3. The method of claim 2, wherein the set of parameters consists of at least one parameter that is selected from a list consisting of an area of the touch, a shape of the touch, an area bounded by the touch, a location of the touch, and a number of points of contact in the touch.

4. The method of claim 2, wherein the set of parameter consists of at least one of the parameters that is selected from a list consisting of a velocity of the touch, a rate of change in area of the touch, and a rate of change in shape of the touch.

5. The method of claim 2, wherein the generating of the set of parameters in (ii) comprises:

(1) recording values for a set of characteristics associated with the touch

(2) determining a rate of change of a first characteristic in the set of characteristics; and

(3) providing the rate of change of the first characteristic as one of the parameters in the set of parameters.

6. The method of claim 1, wherein the determining in (b) comprises:

(i) providing a reliability value of the touch to a software module, the reliability value based on a set of parameters; and

(ii) determining the confidence level of the touch based on the reliability value and an activity context.

7. The method of claim 6, wherein the providing in (i) is performed by a device driver and the providing comprises:

(1) generating the set of parameters related to the touch; and

(2) calculating the reliability value based on the set of parameters.

8. The method of claim 6, wherein the determining in (ii) comprises:

(1) evaluating changes in the reliability value over time; and

(2) determining whether the touch is provided in a window of an application.

9. The method of claim 1, wherein the determining in (b) comprises:

(i) receiving a reliability value of the touch from a driver; and

(ii) evaluating the touch in view of the reliability value and an activity context.

10. The method of claim 9, wherein the touch-sensitive device is a touch-sensitive display and the activity context includes at least one factor selected from the list consisting of a determination of whether the location of the touch is in a window associated with an application, a determination of an active application, a determination of a state of the application, a determination of an active region in a window, a determination of whether multiple inputs are being provided, a determination of whether multiple inputs are expected to be provide substantially simultaneously, a determination of whether a profile of the touch matches a known gesture, and a determination of whether another valid touch is being made in a different location on the touch-sensitive display.

11. A computer readable medium including computer executable instructions for performing the steps of:

(a) receiving a touch input from a touch-sensitive display, the touch input including a location of a touch on the touch-sensitive display and a reliability value;

(b) determining activity context for the touch; and

(c) determining a confidence level for the touch based on the reliability value and the activity context.

12. The computer readable medium of claim 11, wherein the determining of activity context in (b) comprises:

(i) determining an active application;

(ii) determining whether the location of the touch is inside a window associated with the active window; and

(iii) determining whether the touch matches an expected gesture.

13. The computer readable medium of claim 11, wherein the determining the confidence level in (c) comprises:

(i) determining variability of the reliability value over time, and

(ii) reducing the confidence level as variability in the reliability value increases.

14. The computer readable medium of claim 11, wherein the determining in (c) comprises:

(i) determining whether the location of the touch is a window configured to receiving a simple touch input; and

(ii) if the location is in the window, setting the confidence level to high.

15. The computer readable medium of claim 11, further comprising:

(d) if the confidence level exceeds a predetermined level, transmitting an input associated with the location of the touch to an application.

16. The computer readable medium of claim 11, further comprising:

(d) if the confidence level does not exceed a predetermined level but does exceed a threshold level, providing a visual indication on the display near the touch.

17. A method of rejecting unintentional input to a touch-sensitive display, the method comprising:

(a) receiving a first touch on the touch-sensitive display;

(b) providing a first level of filtering to the first touch;

(c) generating a first reliability value based on a set of parameters;

(d) determining a first confidence level based on the first reliability value and an activity context; and

(e) if the confidence level is not high enough, rejecting the first touch as an input.

18. The method of claim 17, wherein (a)-(e) are repeated for a second touch.

19. The method of claim 18, wherein the second touch is being applied at substantially the same time as the first touch.

20. The method of claim 17, wherein the determining in (d) comprises:

(i) determining the variability of the reliability value over time.