Data processing in relation to a multi-touch sensing apparatus

• US 9,158,401 B2
• Filed: 06/29/2011
• Issued: 10/13/2015
• Est. Priority Date: 07/01/2010
• Status: Active Grant

• Current Assignee: FlatFrog Laboratories AB
• Original Assignee: FlatFrog Laboratories AB
• Inventors: Christiansson, Tomas, Fhraeus, Christer, Wassvik, Ola
• Primary Examiner(s): Pervan, Michael
• Application Number:
  US13/807,159
• Publication Number:
  US 20130154983A1
• Time in Patent Office: 1,567 Days
• Field of Search: 178 1801- 1907, 345173-178
• US Class Current: 1/1
• 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 2203/04808 Several contacts: gestures triggering a specific function, e.g. scrolling, zooming, right-click, when the user establishes several contacts with the surface simultaneously; e.g. using several fingers or a combination of fingers and pen
• CPC Class Codes: G06F 3/041 Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
• CPC Class Codes: G06F 3/04166 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 3/04186 Touch location disambiguation
• 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 3/04883 for inputting data by handwriting, e.g. gesture or text

Abstract

A device obtains a signal representative of objects on a touch surface of a multi-touch sensing apparatus and executes a method for extracting touch data from the signal. The method operates in a sequence of detection frames. Each detection frame comprises the steps of: obtaining (300) the signal; processing (301) the signal for identifying touches; determining (302) a set of identified touches and touch data for the set of identified touches; and outputting (303) the touch data. At least one of the steps of processing (301) and determining (302) includes a prioritization that actively favors certain touches to be identified and included in the set of identified touches, respectively. Temporal prioritization favors a touch that corresponds to a previous touch, which is identified in one or more preceding detection frames. Spatial prioritization favors a touch that is located within at least one predefined subarea on the touch surface. The and prioritization enables the touch data to be generated in way that is predictable, consistent and in accordance with user expectations within a general or specific context.

Claims

1. A method for extracting data from a multi-touch sensing apparatus, wherein said method operates in a sequence of detection frames, each detection frame comprising:

obtaining at least one signal representative of objects on a touch surface of the sensing apparatus;

processing said at least one signal for identifying a number of touches and determining age data for each touch, the age data representing a number of preceding detection frames in which the touch is deemed to be identified,

determining a set of identified touches and touch data for the set of identified touches; and

outputting the touch data;

wherein the set of identified touches is limited to a predefined maximum number of identified touches and wherein said set of identified touches is selected among the number of touches based on the age data.

2. A non-transitory computer program product comprising computer code which, when executed on a data-processing system, is adapted to carry out a method of claim 1.

3. A device for generating touch data, said device comprising:

an input; and

a signal processor connected to said input and configured to operate in a sequence of detection frames, each detection frame comprising the steps of obtaining via said input at least one signal representative of objects on a touch surface of a multi-touch sensing apparatus;

processing said at least one signal for identifying a number of touches;

determining age data for each touch, the age data representing a number of preceding detection frames in which the touch is deemed to be identified;

determining a set of identified touches and touch data for the set of identified touches; and

outputting said touch data;

wherein the set of identified touches is limited to a predefined maximum number of identified touches and wherein said set of identified touches is selected among the number of touches based on the age data.

4. A multi-touch sensing apparatus, comprising:

a touch surface, a plurality of sensors arranged within and/or around the touch surface and adapted to generate at least one signal representative of objects on the touch surface, and the device of claim 3.

5. A method for extracting data from a multi-touch sensing apparatus, said method comprising:

obtaining at least one signal representative of objects on a touch surface of the sensing apparatus;

processing said at least one signal for identifying a number of touches;

determining age data for each touch, the age data representing a number of preceding detection frames in which the touch is deemed to be identified;

determining a set of identified touches and touch data for the set of identified touches; and

outputting the touch data;

wherein the set of identified touches is limited to a predefined maximum number of identified touches and wherein said set of identified touches is selected among the number of touches based on the age data.

6. The method of claim 5, further comprising applying a maximum limit to the number of touches to be included in the set of identified touches.