Abstract: A touch system is described having a method of determining touch of one or more objects on a touch surface of a touch-sensitive apparatus, wherein the method operates in a time sequence of frames, each frame comprising the steps of: for a current frame, processing an output signal of the touch sensitive apparatus to generate one or more touch traces, each touch trace having one or more characteristics; and outputting a confirmed touch signal for each touch trace having a touch trace matching at least one of said one or more characteristics in a first number of frames preceding the current frame, wherein the first number of frames is determined in dependence on said one or more characteristics.

Abstract: An optical IR touch sensing apparatus configured to determine, based on output signals of light detectors, a light energy value for each light path across a touch surface, and generate a transmission value for each light path based on the light energy value. A processor is then configured to process the transmission values to determine an object reference point on the touch surface where the light is attenuated or occluded by an object and determine, from a set of light paths unaffected by an object, a set of object boundary light paths comprising one or more light paths passing closest to the object reference point. The characteristics of the object may then be determined in dependence on the set of object boundary light paths.

Abstract: A method of operating an optical touch apparatus is described wherein, the optical touch apparatus comprising a panel, a plurality of emitters and a plurality of detectors arranged with respect to the panel, the plurality of detectors configured to receive light from the plurality of emitters thereby defining detection samples of light transmitted between pairs of emitters and detectors. The optical touch apparatus being further configured to operate in an ambient light evaluation mode comprising the steps of: generating a first set of samples over a first integration time and a second set of samples over a second integration time using at least one detector, and applying a filter to at least the first and second set of samples to generate a residual ambient light value indicative of ambient light noise, wherein the touch apparatus is configured to perform the following steps: operating according to the ambient light evaluation mode for a plurality of repetitions.

Abstract: An optical IR touch sensing apparatus configured to determine, based on output signals of light detectors, a light energy value for each light path across a touch surface, and generate a transmission value for each light path based on the light energy value. A processor is then configured to process the transmission values to determine an object reference point on the touch surface where the light is attenuated or occluded by an object and determine, from a set of light paths unaffected by an object, a set of object boundary light paths comprising one or more light paths passing closest to the object reference point. The characteristics of the object may then be determined in dependence on the set of object boundary light paths.

Abstract: The present application describes a touch sensitive device comprising a touch sensor and a wireless receiver. The touch sensitive device is configured to: identify a new touch interaction at a position on the touch surface, receive a signal from a pen comprising a unique identifier, and match the new touch interaction to the one or more unique identifiers. The new touch interaction is matched to one of the unique identifiers in dependence on a confidence value of each of the unique identifiers and wherein the confidence value of each unique identifier is determined in dependence on characteristics of a previous touch interaction matched to the respective unique identifier.

Abstract: A method of operating an optical touch apparatus is described wherein, the optical touch apparatus comprising a panel, a plurality of emitters and a plurality of detectors arranged with respect to the panel, the plurality of detectors configured to receive light from the plurality of emitters thereby defining detection samples of light transmitted between pairs of emitters and detectors. The optical touch apparatus being further configured to operate in an ambient light evaluation mode comprising the steps of: generating a first set of samples over a first integration time and a second set of samples over a second integration time using at least one detector, and applying a filter to at least the first and second set of samples to generate a residual ambient light value indicative of ambient light noise, wherein the touch apparatus is configured to perform the following steps: operating according to the ambient light evaluation mode for a plurality of repetitions.

Abstract: An optical IR touch sensing apparatus configured to determine, based on output signals of light detectors, a light energy value for each light path across a touch surface, and generate a transmission value for each light path based on the light energy value. A processor is then configured to process the transmission values to determine an object reference point on the touch surface where the light is attenuated or occluded by an object and determine, from a set of light paths unaffected by an object, a set of object boundary light paths comprising one or more light paths passing closest to the object reference point. The characteristics of the object may then be determined in dependence on the set of object boundary light paths.

Abstract: A method of controlling an interaction between a stylus and a touch sensitive device is disclosed. The stylus comprises a unique identifier and a wireless transmitter for wireless transmission of the unique identifier. The touch sensitive device comprises a wireless receiver for wirelessly receiving the unique identifier of one or more styluses. The method comprises transmitting the unique identifier from a first stylus to the touch sensitive device, determining from a database, a set of controls associated with the unique identifier, and controlling the interaction between the touch sensitive device and the user of the first stylus according to the set of controls. A touch interaction system is also disclosed.

Abstract: A stylus is described for controlling a computer device. The stylus comprises at least one user control and a contact sensor configured to detect a contact between the controller device and a touch surface. The stylus is configured to: detect an activation of the user control; whilst the user control continues to be activated, detecting, using the contact sensor, whether a contact between the controller device and a touch surface has occurred and transmitting a first control signal when a contact is detected, where no contact is detected, transmitting a second control signal when the user control is deactivated.

Abstract: A method of operating an optical touch apparatus is described wherein, the optical touch apparatus comprising a panel, a plurality of emitters and a plurality of detectors arranged with respect to the panel, the plurality of detectors configured to receive light from the plurality of emitters thereby defining detection samples of light transmitted between pairs of emitters and detectors. The optical touch apparatus being further configured to operate in an ambient light evaluation mode comprising the steps of: generating a first set of samples over a first integration time and a second set of samples over a second integration time using at least one detector, and applying a filter to at least the first and second set of samples to generate a residual ambient light value indicative of ambient light noise, wherein the touch apparatus is configured to perform the following steps: operating according to the ambient light evaluation mode for a plurality of repetitions.

Abstract: Touch sensitivity is enabled using a touch system that comprises a panel configured to conduct signals, along detection lines across a touch surface. A signal processor operates in a sequence of repetitions to: generate data samples that represent detected signal energy on the actual detection lines; generate based on the data samples, an interpolated sinogram comprising interpolation samples that represent fictitious detection lines which have a desired location on the touch surface; and reconstruct a signal interaction pattern for the touch surface based on the interpolated sinogram. The signal processor implements an error correction to counteract the influence of a change in validity status for a data sample among the data samples, by identifying interpolation samples affected by the change in validity status, and by setting each identified interpolation sample to a value that maintains a relative signal transmission of the fictitious detection line from a former repetition.

Abstract: A signal processor implements a technique for detecting objects on a panel which transmits signals inside the panel such that the objects are allowed to interact with (e.g. attenuate) the signals by contact with a touch surface of the panel. The signal processor operates to define cells that have a given location on the touch surface and are associated with a respective set of intersecting paths for the signals across the touch surface. The signal processor operates to obtain (90) an output signal from a signal detection arrangement that measures a signal property for each path; process (91) the output signal to obtain an interaction value for each path; and generate (93-95?) a cell value of a selected cell among the cells as either a robust measure of central tendency (e.g. a median) or a minimum/maximum among the interaction values for the intersecting paths. The signal processor determines (97) presence or absence of an object in the selected cell based on the cell value.

Abstract: A device implements a method for detecting contamination of an FTIR-based panel. The apparatus generates projection signals representing detection lines that have propagated on a plurality of propagation paths by total internal reflection (TIR) inside a transmissive panel such that contamination on the panel surface causes attenuation (frustration) of at least one of the projection signals. The device generates a transmission value for each detection line in the transmissive panel, and determines the presence of contamination on the surface of the panel by comparing the transmission values according to at least one of the presented comparison techniques.

Abstract: A device implements a method for estimating the application force of a touching object onto a touch surface in an FTIR-based projection-type touch-sensing apparatus. The apparatus generates projection signals representing radiation that has propagated on a plurality of propagation paths by total internal reflection (TIR) inside a transmissive panel beneath a touch surface of the transmissive panel such that a touching object on the touch surface causes attenuation (frustration) of at least one of the projection signals. The device generates a time series of force values, which represent the application force, based on a time series of magnitude values, which represent a magnitude of a peak in two-dimensional interaction patterns generated by image reconstruction processing of the projection signals, the peak corresponding to the touching object on the touch surface. The force estimation may involve one or more corrections.

Abstract: An optical IR touch sensing apparatus configured to determine, based on output signals of light detectors, a light energy value for each light path across a touch surface, and generate a transmission value for each light path based on the light energy value. A processor is then configured to process the transmission values to determine an object reference point on the touch surface where the light is attenuated or occluded by an object and determine, from a set of light paths unaffected by an object, a set of object boundary light paths comprising one or more light paths passing closest to the object reference point. The characteristics of the object may then be determined in dependence on the set of object boundary light paths.

Abstract: An optical IR touch sensing apparatus configured to determine, based on output signals of light detectors, a light energy value for each light path across a touch surface, and generate a transmission value for each light path based on the light energy value. A processor is then configured to process the transmission values to determine a region around the object reference point on the touch surface and a set of light paths intersecting the region. By performing statistical analysis of the set of light paths, characteristics of the object may be determined.

Abstract: Touch sensitivity is enabled using a touch system that comprises a panel configured to conduct signals along detection lines across a touch surface. A signal processor obtains observed values for the detection lines, and identifies an interaction pattern on the touch surface as a solution to a function that comprises an aggregation of differences, for each detection line, between the observed value and a projected value, which is given by a projection function that defines a functional relation between the interaction pattern and the projected value for each detection line. The signal processor implements a normalization to ensure that the interaction pattern indicates weak touches even in the presence of strong touches.

Abstract: A signal processor in a touch-sensitive apparatus generates a 2D representation of touch interaction on a touch surface by tomographic processing. The signal processor generates observed values for detection lines that correspond to signal propagation paths across the touch surface. The observed values correspond to sampling points in a sample space defined by a first dimension representing a rotation angle of the detection line on the touch surface and a second dimension representing a distance of the detection line from a predetermined origin on the touch surface. The signal processor processes the observed values, by interpolation in the sample space, to generate estimated values for matched sampling points in the sample space using a tomographic reconstruction function.

Abstract: A device implements a method of tracking objects on a touch surface of an FTIR based touch-sensitive apparatus. An interaction map is generated that indicates local changes in interaction on the touch surface. The interaction map is processed for identification of positive and negative peaks that represent a locally increased and decreased interaction in the interaction map, respectively. To suppress the impact of interferences, a dedicated first heuristic and/or second heuristic is applied to identify potentially false peaks among the positive peaks. The first heuristic designates a positive peak as a potentially false peak when the positive peak is deemed to be associated with one or more of the negative peaks. The second heuristic designates a positive peak as a potentially false peak when the positive peak is deemed to be located along one of the movement trajectories.

Abstract: A method, gesture interpretation unit and touch sensing device receiving touch input data indicating touch inputs on a touch surface of the touch sensing device, wherein the touch input data comprises positioning data and pressure data for each touch input, and determining from the touch input data: first, second and third touch input from a first, a second and a third object on the touch surface, and wherein the first, second and third objects are present on the touch surface during overlapping time periods; and while continuous contact of the first, second and third objects with the touch surface is maintained: calculating a geometric center of mass, and a pressure center of mass, for the first, second and third touch inputs; comparing the GCM with the determining a movement vector based on the result of the comparison; and moving the graphical interactive object in relation to the movement vector.