Multi-touch input discrimination

• US 9,778,807 B2
• Filed: 12/30/2015
• Issued: 10/03/2017
• Est. Priority Date: 01/03/2007
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Westerman, Wayne Carl
• Primary Examiner(s): MARINELLI, PATRICK
• Application Number:
  US14/985,233
• Publication Number:
  US 20160110027A1
• Time in Patent Office: 643 Days
• Field of Search: 345156-184, 345104, 178 1801- 2004, 715863
• CPC Class Codes: G06F 2203/04101 2.5D-digitiser, i.e. digitiser detecting the X/Y position of the input means, finger or stylus, also when it does not touch, but is proximate to the digitiser's interaction surface and also measures the distance of the input means within a short range in the Z direction, possibly with a separate measurement setup
• 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 3/041 Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
• 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 3/04182 Filtering of noise external to the device and not generated by digitiser components
• CPC Class Codes: G06F 3/0421 by interrupting or reflecting a light beam, e.g. optical touch-screen
• CPC Class Codes: G06F 3/044 by capacitive means
• CPC Class Codes: G06F 3/0488 using a touch-screen or digitiser, e.g. input of commands through traced gestures
• CPC Class Codes: G06T 7/11 Region-based segmentation
• CPC Class Codes: G06V 40/107 Static hand or arm
• CPC Class Codes: G09G 2320/0606 Manual adjustment
• CPC Class Codes: G09G 2320/0626 for control of overall brightness
• CPC Class Codes: G09G 2320/0633 by amplitude modulation of the brightness of the illumination source
• CPC Class Codes: G09G 2320/0653 Controlling or limiting the speed of brightness adjustment of the illumination source
• CPC Class Codes: G09G 2330/021 Power management, e.g. power saving
• CPC Class Codes: G09G 2360/144 the light being ambient light
• CPC Class Codes: G09G 3/20 for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
• CPC Class Codes: G09G 3/2003 Display of colours specific for liquid crystal displays G09G3/3607
• CPC Class Codes: G09G 5/10 Intensity circuits

Abstract

Techniques for identifying and discriminating between different types of contacts to a multi-touch touch-screen device are described. Illustrative contact types include fingertips, thumbs, palms and cheeks. By way of example, thumb contacts may be distinguished from fingertip contacts using a patch eccentricity parameter. In addition, by non-linearly deemphasizing pixels in a touch-surface image, a reliable means of distinguishing between large objects (e.g., palms) from smaller objects (e.g., fingertips, thumbs and a stylus) is described.

Claims

1. A method to identify an input to a touch-surface device, comprising:

obtaining a proximity image from an array of sensing elements;

segmenting the proximity image to identify one or more patches;

generating a proximity sensor signal when an object is proximate a proximity sensor, the proximity sensor distinct from the array of sensing elements;

determining a signal density value for at least one of the one or more patches; and

using the signal density value and the proximity sensor signal to determine an object adjacent to or in contact with the touch-surface device; and

wherein each patch has a plurality of pixels and each pixel has a pixel value and the signal density value is determined by dividing the sum of all pixel values in a patch by a radius of the patch.

2. The method of claim 1, wherein the radius of the patch comprises a geometric mean radius of the patch.

3. The method of claim 1, further comprising performing a control operation of the touch-surface device based on the determining of the object adjacent to or in contact with the touch-surface touch surface device.

4. The method of claim 3, wherein the control operation comprises causing the touch-surface device to change an operational state.

5. The method of claim 3, wherein the control operation comprises performing a specified function.

6. The method of claim 3, wherein the control operation comprises ignoring the object contacting the touch-surface.

7. The method of claim 1, wherein the touch-surface device comprises one of the devices selected from the group consisting of:

a tablet computer system, a hand-held computer system, a portable music player system, a portable video player system.

8. The method of claim 1, wherein the touch-surface device comprises a mobile telephone.

9. The method of claim 1, wherein using the signal density value and the proximity sensor signal for determining the object adjacent to or in contact with the touch-surface device comprises, in part, utilizing threshold values of the signal density to discriminate when an object is hovering over the touch-surface device or in contact with the touch-surface device.

10. A program storage device, readable by a programmable control device, comprising instructions stored thereon for causing the programmable control device to perform the method of claim 1.

11. A touch-surface device, comprising:

a memory for storing a proximity image of a touch surface of the touch-surface device, the proximity image obtained from an array of sensing elements;

a processor operative for;

segmenting the proximity image to identify one or more patches;

generating a proximity sensor signal when an object is proximate a proximity sensor, the proximity sensor distinct from the array of sensing elements;

determining a signal density value for at least one of the one or more patches; and

using the signal density value and the proximity sensor signal for determining an object adjacent to or in contact with the touch-surface device; and

wherein each patch has a plurality of pixels and each pixel has a pixel value and the signal density value is determined by dividing the sum of all pixel values in a patch by a radius of the patch.

12. A touch surface device as recited in claim 11 wherein the radius of the patch comprises a geometric mean radius of the patch.

13. A touch surface device, comprising:

a memory for storing a proximity image of a touch surface of the touch-surface device, the proximity image obtained from an array of sensing elements;

a processor operative for;

segmenting the proximity image to identify one or more patches;

generating a proximity sensor signal when an object is proximate a proximity sensor, the proximity sensor distinct from the array of sensing elements;

determining a signal density value for at least one of the one or more patches; and

using the signal density value and the proximity sensor signal for determining an object adjacent to or in contact with the touch-surface device; and

wherein each patch has a plurality of pixels and each pixel has a pixel value and the signal density value is determined by dividing a sum of all pixel values in a patch by the number of pixels in the patch.

14. A method to identify an input to a touch-surface device, comprising:

obtaining a proximity image from an array of sensing elements;

segmenting the proximity image to identify one or more patches;

generating a proximity sensor signal when an object is proximate a proximity sensor, the proximity sensor distinct from the array of sensing elements;

determining a signal density value for at least one of the one or more patches; and

using the signal density value and the proximity sensor signal to determine an object adjacent to or in contact with the touch-surface device; and

wherein each patch has a plurality of pixels and each pixel has a pixel value and the signal density value is determined by dividing a sum of all pixel values in a patch by the number of pixels in the patch.

15. A program storage device, readable by a programmable control device, comprising instructions stored thereon for causing the programmable control device to perform the method of claim 14.

16. The method of claim 14, wherein using the signal density value and the proximity sensor signal for determining the object adjacent to or in contact with the touch-surface device comprises, in part, utilizing threshold values of the signal density to discriminate when an object is hovering over the touch-surface device or in contact with the touch-surface device.

17. A method to identify an input to a touch-surface device, comprising:

obtaining a proximity image from an array of sensing elements;

segmenting the proximity image to identify one or more patches;

generating a proximity sensor signal when an object is proximate a proximity sensor, the proximity sensor distinct from the array of sensing elements;

determining a signal density value for at least one of the one or more patches; and

using the signal density value and the proximity sensor signal to determine an object adjacent to or in contact with the touch-surface device; and

wherein each patch has a plurality of pixels and each pixel has a pixel value and the signal density value is determined by dividing the sum of all pixel values in a patch by the area of the patch.

18. A program storage device, readable by a programmable control device, comprising instructions stored thereon for causing the programmable control device to perform the method of claim 17.

19. The method of claim 17, wherein using the signal density value and the proximity sensor signal for determining the object adjacent to or in contact with the touch-surface device comprises, in part, utilizing threshold values of the signal density to discriminate when an object is hovering over the touch-surface device or in contact with the touch-surface device.