Patent application number | Description | Published |
20110074734 | DETECTING THE LOCATION OF AN OBJECT ON A TOUCH SURFACE - An apparatus is operated to determine the location of at least one object on a touch surface of a light transmissive panel. In the apparatus, an illumination arrangement introduces radiation into the panel for propagation by internal reflection between the touch surface and the opposite surface, so as to generate a grid of intersecting radiation paths in a sensing area, and a detection arrangement measures the transmitted energy in the radiation paths. A data processor then determines, based on the transmitted energy, the location based on an attenuation of two or more radiation paths caused by the object touching the touch surface within the sensing area. In the apparatus, the illumination arrangement generates at least a subset of the radiation paths by sweeping at least one beam of radiation along the touch surface. The detection arrangement comprises a fixed re-directing device which receives and re-directs the beam onto a common detection point while the beam is swept along the touch surface, and a radiation detector which is located at the common detection point to measure the energy of the beam(s). | 03-31-2011 |
20110074735 | DETECTING THE LOCATIONS OF A PLURALITY OF OBJECTS ON A TOUCH SURFACE - An apparatus is controlled to detect locations of a plurality of objects on a touch surface of a panel. An input scanner arrangement introduces at least three beams of radiation into the panel for propagation by internal reflection, and sweeps the beams inside the panel across a sensing area, preferably in at least two different principal directions. At least one radiation detector is arranged to receive the beams from the input scanner arrangement while they are swept across the sensing area. A data processor is connected to the radiation detector(s) and operated to identify the locations based on an attenuation of the beams caused by the objects touching the touch surface within the sensing area, the attenuation being identifiable from an output signal of the radiation detector(s). Each output signal may be further processed to generate a transmission signal, by dividing the output signal by a background signal which represents the output signal without any object on the touch surface. | 03-31-2011 |
20110090176 | DETERMINING THE LOCATION OF ONE OR MORE OBJECTS ON A TOUCH SURFACE - A device operates on output signals from a light sensor arrangement in a touch-sensing apparatus to determine a position of an object on a touch surface. The apparatus includes a light transmissive panel that defines the touch surface and an opposite surface. A light source arrangement provides sheets of light inside the panel, wherein each sheet comprises light that propagates by internal reflection between the touch surface and the opposite surface from one or more incoupling points to a set of outcoupling points. The light sensor arrangement generates the output signals, which represent light reaching the outcoupling points. The apparatus is configured such that an object touching the touch surface locally attenuates at least two sheets of light. To determine the position, the device identifies, in the output signals, a set of signal profiles originating from said object. The device determines at least part of an attenuated light path across the panel based on each signal profile, and identifies the position of the object on the touch surface based on the thus-determined attenuated light paths. In determining the attenuated light path, the device applies a predetermined width function which is representative of a dependence of signal profile width on distance to the incoupling point due to light scattering caused by at least one of the touch surface and the opposite surface. | 04-21-2011 |
20110227874 | TOUCH SENSING APPARATUS AND METHOD OF OPERATING THE SAME - A touch sensing apparatus is controlled to determine the position of one or more objects ( | 09-22-2011 |
20120068973 | Determining The Location Of An Object On A Touch Surface - An apparatus is operated to determine the location of at least one object on a touch surface ( | 03-22-2012 |
20120162142 | TOUCH-SENSITIVE SYSTEM AND METHOD FOR CONTROLLING THE OPERATION THEREOF - A touch-sensitive system comprises a light transmissive panel defining a touch surface and an opposite surface; an illumination arrangement comprising emitters configured to introduce light into the panel for propagation in the panel in an emission pattern; a light detection arrangement comprising detectors configured to receive the light propagating in the panel. A control unit is arranged to control the operation of the touch-sensitive system. The control unit executes a control method to monitor the light received in the light detecting arrangement for detection of touches on the touch surface, the touches attenuating the light propagating in the panel. The control method also selects a mode for the emission pattern in dependence of the occurrence of touches on the touch surface and controls the emission pattern in accordance with the selected mode. | 06-28-2012 |
20120162144 | Touch Surface With A Compensated Signal Profile - An apparatus, method and computer-readable medium for determining a location of at least one object on a touch surface of a light transmissive panel. The method comprises the steps of: introducing light into the panel for propagation by internal reflection between the touch surface and an opposite surface; receiving the light propagating in the panel; and iteratively i) determining a current signal profile of light received by the light detection arrangement, ii) updating, when a condition is met, a background signal profile of light received by the light detection arrangement, iii) calculating a current compensated signal profile as a function of the background signal profile and the current signal profile and iv) determining, when the object touches the touch surface and thereby attenuates the light propagating in the panel, the location as a function of the compensated signal profile. | 06-28-2012 |
20120169672 | TOUCH SURFACE WITH VARIABLE REFRACTIVE INDEX - An apparatus for determining a location of at least one object on a touch surface, comprising: a light transmissive panel defining the touch surface and including a controllable reflective boundary; an illumination arrangement configured to introduce light into the panel; a control device configured to selectively control the reflective boundary such that the light may pass between a first layer and a second layer via an opening in the reflective boundary; a light detection arrangement configured to measure the light passed via the opening and impinged on the touch surface; and a processor unit configured to determine the location as a function of the measured light passed via the opening and the selective control of the reflective boundary. A method and computer readable medium is also described. | 07-05-2012 |
20120200538 | TOUCH SURFACE WITH TWO-DIMENSIONAL COMPENSATION - An apparatus for determining an interaction between an object and a touch surface of a panel. An illumination arrangement introduces light into the panel for propagation by internal reflection between the touch surface and an opposite surface and towards a receiving light detection arrangement. A processor unit is configured to iteratively i) determine, based on the received light, a current light status representing a two-dimensional distribution of light in the panel, ii) determine the interaction with the object as a function of the current light status and a previously updated background status representing a two-dimensional distribution of light in the panel caused by contaminations, and iii) update the background status as a function of the interaction. A method and computer readable medium are also described. | 08-09-2012 |
20120212441 | DETERMINING TOUCH DATA FOR ONE OR MORE OBJECTS ON A TOUCH SURFACE - A touch-sensing apparatus comprises a light transmissive panel, in which sheets of light are propagated by internal reflection between a touch surface and an opposite surface from an incoupling site to an outcoupling site. The touch-sensing apparatus is configured such that objects touching the touch surface cause a local attenuation of at least two sheets of light. A light sensor arrangement is optically connected to the outcoupling site to measure transmitted light energy. A data processor is connected to the light sensor arrangement and configured to execute a touch determination process. The process operates on at least one projection signal which is indicative of a spatial distribution of light within the outcoupling site. | 08-23-2012 |
20120256882 | TOUCH SURFACE WITH IDENTIFICATION OF REDUCED PERFORMANCE - A device is configured to process data from a touch-sensitive apparatus for the purpose of identifying a reduced performance of components in the apparatus. The apparatus may be an FTIR system that comprises a light transmissive panel, an illumination arrangement for introducing light into the panel, and a light detection arrangement for receiving the light propagating in the panel and for measuring the energy of the received light. The device comprises a processor unit which is configured to obtain a signal comprising a time series of signal values that represent the energy of the light received by the light detection arrangement; calculate a parameter value representing a temporal variability of the signal values in the signal; and identify, based on the parameter value, a reduced performance of any of the illumination arrangement and the light detection arrangement. The temporal variability may be calculated to represent one of an absolute noise level and a signal-to-noise ratio of the signal, and enables the reduced performance to be identified while objects touch the light transmissive panel. | 10-11-2012 |
20120268403 | EXTRACTING TOUCH DATA THAT REPRESENTS ONE OR MORE OBJECTS ON A TOUCH SURFACE - A touch-sensing apparatus is based on frustrated total internal reflection (FTIR). The apparatus comprises a panel, in which sheets of light are propagated by internal reflection between a touch surface and an opposite surface. A light sensor arrangement is optically connected to the panel to measure transmitted light energy on detection lines across the touch surface. Each detection line represents a light path across the touch surface from a light source to a light sensor. An object that touches the touch surface will frustrate the propagating light and cause a local attenuation among the detection lines. A data processor is connected to the light sensor arrangement and configured to execute a process for extracting touch-related data. | 10-25-2012 |
20130044073 | TOUCH DETERMINATION BY TOMOGRAPHIC RECONSTRUCTION - A touch-sensitive apparatus comprises a panel configured to conduct signals from a plurality of peripheral incoupling points to a plurality of peripheral outcoupling points. Actual detection lines are defined between pairs of incoupling and outcoupling points to extend across a surface portion of the panel. The signals may be in the form of light, and objects touching the surface portion may affect the light via frustrated total internal reflection (FTIR). A signal generator is coupled to the incoupling points to generate the signals, and a signal detector is coupled to the out-coupling points to generate an output signal. A data processor operates on the output signal to enable identification of touching objects. The output signal is processed ( | 02-21-2013 |
20130154983 | DATA PROCESSING IN RELATION TO A MULTI-TOUCH SENSING APPARATUS - 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 ( | 06-20-2013 |
20130285968 | TOUCH DETERMINATION WITH SIGNAL ENHANCEMENT - Multi-touch sensitivity is enabled using a touch-sensitive apparatus comprising a panel for conducting signals from a plurality of incoupling points to a plurality of outcoupling points, thereby defining detection lines between pairs of incoupling and outcoupling points. Signal generators coupled to the incoupling points generate the signals, and signal detectors coupled to the outcoupling points generate an output signal indicative of one or more touches on the surface portion. A signal processor obtains the output signal which, if converted into a set of data samples of a given input format, enables a predetermined reconstruction algorithm to determine an interaction pattern on the surface portion. The signal processor generates, based on the output signal, a modified set of data samples in the given input format; and operates the predetermined reconstruction algorithm on the modified set of data samples so as to determine a modified interaction pattern on the surface portion. | 10-31-2013 |
20130342490 | TOUCH DETERMINATION WITH SIGNAL COMPENSATION - A multi-touch system includes a panel for conducting signals, e.g. by FTIR, from incoupling points to outcoupling points, to define detection lines across the panel. A signal processor operates in a repeating sequence of iterations to obtain an output signal from a detector coupled to the outcoupling points and generate a formatted signal value for each detection line, and operate a reconstruction algorithm on the formatted signal values to determine an interaction pattern on the panel. The signal processor also, at least intermittently in the sequence of iterations, operates compensation data on the formatted signal values to compensate for contaminations on the panel, and calculates updated compensation data based on an interference pattern determined as a function of the interaction pattern, the interference pattern being a 2D representation of contamination-induced signal interferences. The influence of contaminations in the interaction pattern is thereby suppressed. | 12-26-2013 |
20140002400 | IMAGE RECONSTRUCTION FOR TOUCH DETERMINATION | 01-02-2014 |
20140055421 | TRACKING OBJECTS ON A TOUCH SURFACE - A device implements a method of tracking objects on a touch surface of an FTIR based touch-sensitive apparatus. The method repeatedly operates to generate an interaction pattern that indicates local changes in interaction on the touch surface, identify apparent peaks in the interaction pattern, and update existing movement trajectories based on the apparent peaks. An error suppression process is executed at least intermittently in the method to process the apparent peaks and/or the existing movement trajectories to identify implicated trajectories with a potential tracking problem, define two or more movement propositions for each implicated trajectory, and cause an evaluation of the movement propositions in one or more subsequent repetitions of the method. The error suppression process improves tracking by postponing the final decision on how to track the object of the implicated trajectory until more information is available. | 02-27-2014 |
20140085241 | DEVICE AND METHOD FOR DETERMINING REDUCED PERFORMANCE OF A TOUCH SENSITIVE APPARATUS - A device for processing data from a touch sensitive apparatus is provided. The apparatus includes a light transmitting panel with a touch surface and an opposed back surface, an illumination arrangement configured to introduce light into the panel for propagation by internal reflection between the touch surface and the back surface, and a light detection arrangement configured to receive the light after propagation in the panel. A processor unit in the device obtains a monitored signal which is functionally dependent on transmitted light detected by the light detection arrangement; reconstructs, based on the monitored signal, a two-dimensional attenuation field representing an attenuation of the transmitted light on the touch surface; calculates an expected monitored signal based on the reconstructed attenuation field; and compares the expected monitored signal with the monitored signal in order to determine a reduced performance of the apparatus. | 03-27-2014 |
20140125633 | TOUCH SENSING APPARATUS AND METHOD OF OPERATING THE SAME - A touch sensing apparatus includes a group of emitters arranged to emit light to illuminate at least part of the touch surface, a light detector arranged to receive light from the group of emitters, and a processing element. Each emitter is controlled to transmit a code by way of the emitted light such that the code identifies the respective emitter. The codes may at least partly be transmitted concurrently. The codes may be selected such that a value of an autocorrelation of each code is significantly higher than a value of a cross-correlation between any two codes of different emitters. The processing element processes an output signal from the light detector to separate the light received from the individual emitters based on the transmitted codes, and to determine the position of the object/objects based on the light received from the individual emitters. | 05-08-2014 |
20140267124 | TOUCH DETERMINATION BY TOMOGRAPHIC RECONSTRUCTION - A touch-sensitive apparatus comprises a panel configured to conduct signals from a plurality of peripheral incoupling points to a plurality of peripheral outcoupling points. Actual detection lines are defined between pairs of incoupling and outcoupling points to extend across a surface portion of the panel. The signals may be in the form of light, and objects touching the surface portion may affect the light via frustrated total internal reflection (FTIR). A signal generator is coupled to the incoupling points to generate the signals, and a signal detector is coupled to the outcoupling points to generate an output signal. A data processor operates on the output signal to enable identification of touching objects. The output signal is processed ( | 09-18-2014 |
20140300572 | TOUCH DETERMINATION BY TOMOGRAPHIC RECONSTRUCTION - Objects touching a surface portion attenuate transmitted signals. A data processor processes an output signal from a detector coupled to the outcoupling points, to generate a set of data samples indicative of detected energy for the actual detection lines. The set of data samples is further processed to generate a set of matched samples indicative of estimated detected energy for fictitious detection lines that extend across the surface portion in parallel groups at a plurality of different angles. The individual spacing between the fictitious detection lines in each group and the individual difference in angle between said groups are selected such that the set of matched samples transforms to Fourier coefficients arranged as data points on a pseudo-polar grid in a Fourier domain. The set of matched samples is processed by tomographic reconstruction to generate a two-dimensional distribution of an interaction parameter within the surface portion. | 10-09-2014 |
20140368471 | PERFORMANCE MONITORING AND CORRECTION IN A TOUCH-SENSITIVE APPARATUS - Touch sensitivity is enabled using a touch system that comprises a panel configured to conduct signals, e.g. by TIR, 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. | 12-18-2014 |
20140375607 | TRACKING OBJECTS ON A TOUCH SURFACE - A device implements a method of tracking objects on a touch surface of an FTIR based touch-sensitive apparatus. | 12-25-2014 |
20150035774 | EFFICIENT TOMOGRAPHIC PROCESSING FOR TOUCH DETERMINATION - Touch sensitivity is enabled using a touch system that comprises a panel configured to conduct signals, e.g. by TIR, along detection lines across a touch surface. A signal processor operates to generate data samples indicative of transmitted signal energy on parallel detection lines at a number of different angles across the touch surface; process the data samples for generation of interpolated Fourier coefficients at grid points in a regular grid in a Fourier domain; and operate a two-dimensional inverse Fourier transform on the interpolated Fourier coefficients so as to generate an interaction pattern for the touch surface. The interpolated Fourier coefficients are generated sequentially for individual groups of grid points. Each individual group comprises grid points that have equal distance to an origin in the regular grid, e.g. grid points that are mapped onto each other by one or ore lines of symmetry in the regular grid. The group-based processing may improve processing speed and/or reduce the need for data storage. | 02-05-2015 |
20150035803 | INTEGRATED TOUCH-SENSING DISPLAY APPARATUS AND METHOD OF OPERATING THE SAME - An integrated touch-sensing display is operated to detect the location of one or more objects on a touch surface. The integrated touch-sensing display defines a display area. A light guide ( | 02-05-2015 |
20150054759 | EFFICIENT TOMOGRAPHIC PROCESSING FOR TOUCH DETERMINATION - Touch sensitivity is enabled using a touch system that comprises a panel configured to conduct signals, e.g. by TIR, along detection lines across a rectangular touch surface with first and second spatial dimensions. A signal processor operates to transform energy values for the detection lines into Fourier coefficients arranged as data points on a regular grid defined by first and second frequency dimensions. To generate an interaction pattern for the touch surface, the signal processor operates a first 1D inverse FFT on the data points with respect to the second frequency dimension, so as to generate first values transformed into the second spatial dimension, and operates a second 1D inverse FFT on a selected subset of the first values with respect to the first frequency dimension to generate second values that represent the interaction pattern. The selected subset is defined by the data points that fall within an extent of the touch surface in the second spatial dimension, thereby reducing the total number of inverse FFT operations. | 02-26-2015 |