Patent application number | Description | Published |
20080309622 | Periodic sensor autocalibration and emulation by varying stimulus level - The automatic calibration of a sensor panel is disclosed by varying the amplitude of an input stimulus Vstim to simulate a full-touch condition and calibrating each pixel of the sensor panel in accordance with the difference between the simulated full-touch condition and a baseline full-touch condition. To accomplish this, a baseline full scale output FS_targ_cal can be measured at during pre-delivery calibration for each pixel using a test fixture capable of applying a no-touch to full-touch condition given a nominal Vstim. A full-touch condition can then be emulated for each pixel by lowering Vstim until the current full scale output FS_targ_current equals FS_targ_cal, and determining the Vstim value Vstim_cal at that point. During field calibration, Vstim_cal can be applied to each pixel to simulate a full-touch condition, and FS_targ_current can be obtained and compared against FS_targ_cal. Each analog channel can then be tuned so that in subsequent full-touch conditions, FS_targ_current will approximately equal FS_targ_cal. | 12-18-2008 |
20080309625 | Multiple simultaneous frequency detection - The use of multiple stimulation frequencies and phases to generate an image of touch on a touch sensor panel is disclosed. Each of a plurality of sense channels can be coupled to a column in a touch sensor panel and can have multiple mixers. Each mixer in the sense channel can utilize a circuit capable generating a demodulation frequency of a particular frequency. At each of multiple steps, various phases of selected frequencies can be used to simultaneously stimulate the rows of the touch sensor panel, and the multiple mixers in each sense channel can be configured to demodulate the signal received from the column connected to each sense channel using the selected frequencies. After all steps have been completed, the demodulated signals from the multiple mixers can be used in calculations to determine an image of touch for the touch sensor panel at each frequency. | 12-18-2008 |
20080309628 | Detection of low noise frequencies for multiple frequency sensor panel stimulation - The identification of low noise stimulation frequencies for detecting and localizing touch events on a touch sensor panel is disclosed. Each of a plurality of sense channels can be coupled to a separate sense line in a touch sensor panel and can have multiple mixers, each mixer using a demodulation frequency of a particular frequency, phase and delay. With no stimulation signal applied to any drive lines in the touch sensor panel, pairs of mixers can demodulate the sum of the output of all sense channels using the in-phase (I) and quadrature (Q) signals of a particular frequency. The demodulated outputs of each mixer pair can be used to calculate the magnitude of the noise at that particular frequency, wherein the lower the magnitude, the lower the noise at that frequency. Several low noise frequencies can be selected for use in a subsequent touch sensor panel scan function. | 12-18-2008 |
20090009483 | SINGLE-CHIP TOUCH CONTROLLER WITH INTEGRATED DRIVE SYSTEM - A touch controller for controlling a touch sensor panel is provided. The touch controller includes a plurality of sense channels that receive sensor signals from the touch sensor panel, a drive system that generates a plurality of stimulation signals based on a supply voltage on the order of digital logic level supply voltages, the stimulation signals for simultaneously stimulating multiple drive lines of the touch sensor panel, and a channel controller that controls the sense channels and the drive system. The plurality of sense channels, the drive system, and the channel controller are formed on a single chip. | 01-08-2009 |
20090189867 | Auto Scanning for Multiple Frequency Stimulation Multi-Touch Sensor Panels - The use of multiple stimulation frequencies and phases is disclosed to detect touch events on a touch sensor panel in a low-power state. Simultaneously during every frame, a number of rows of the touch sensor panel can be driven with a positive phase of one or more stimulation signals, and the same number of different rows can be driven with the anti-phase of those same stimulation signals. Because the same number of rows are stimulated with the in-phase and anti-phase components of the one or more stimulation signals, the resulting charges injected into a given column cancel each other out. However, a touch event will create an imbalance, and a non-zero charge will be detected. The detection of the touch event can then trigger the system to wake up, activate a panel processor, and perform a full panel scan, where the location of the touch event can be identified. | 07-30-2009 |
20090212642 | CHARGE RECYCLING FOR MULTI-TOUCH CONTROLLERS - The recycling of charge when two or more of the drive lines of a touch sensor panel are being simultaneously stimulated with the in-phase and anti-phase components of a stimulation signal is disclosed. To perform charge recycling, a discharge path can be selectively formed between drive lines being stimulated with the in-phase and anti-phase components of the stimulation signal. A multiplexer can be coupled to the driver of each drive line and the common discharge path. When charge recycling is to be performed, control logic can configure the multiplexers to isolate the driver and connect the drive lines being stimulated with the in-phase component of the stimulation signal with the drive lines being stimulated with the anti-phase component of the stimulation signal. The capacitance on the charged-up drive lines can then discharge to the capacitance on the discharged drive lines. | 08-27-2009 |
20090244014 | SAR ADC WITH DYNAMIC INPUT SCALING AND OFFSET ADJUSTMENT - An apparatus for generating an image of touch on or about a touch-sensitive surface comprising a touch panel is disclosed. The touch panel can include a plurality of touch sensors configured for detecting one or more touch events occurring at distinct locations at about the same time. Each touch event can comprise a touching of an object against the touch-sensitive surface. A plurality of receive channels can be coupled to the touch panel for generating values representative of detected touch events. The receive channels can include a charge redistribution successive approximation register digital-to-analog converter (SAR ADC) configured to convert an analog waveform into a digital representation via a binary search and outputting the digital representation to an output register. The SAR ADC architecture can be such that it the dynamic input range can be scaled and offset adjusted. | 10-01-2009 |
20090315850 | Multipoint Touch Surface Controller - A multipoint touch surface controller is disclosed herein. The controller includes an integrated circuit including output circuitry for driving a capacitive multi-touch sensor and input circuitry for reading the sensor. Also disclosed herein are various noise rejection and dynamic range enhancement techniques that permit the controller to be used with various sensors in various conditions without reconfiguring hardware. | 12-24-2009 |
20100059295 | Single-chip multi-stimulus sensor controller - A multi-stimulus controller for a multi-touch sensor is formed on a single integrated circuit (single-chip). The multi-stimulus controller includes a transmit oscillator, a transmit signal section that generates a plurality of drive signals based on a frequency of the transmit oscillator, a plurality of transmit channels that transmit the drive signals simultaneously to drive the multi-touch sensor, a receive channel that receives a sense signal resulting from the driving of the multi-touch sensor, a receive oscillator, and a demodulation section that demodulates the received sense signal based on a frequency of the receive oscillator to obtain sensing results, the demodulation section including a demodulator and a vector operator. | 03-11-2010 |
20100060590 | Channel Scan Architecture for Multiple Stimulus Multi-Touch Sensor Panels - A channel scan architecture for detecting touch events on a touch sensor panel is disclosed. The channel scan architecture can combine drive logic, sense channels and channel scan logic on a single monolithic chip. The channel scan logic can be configured to implement a sequence of scanning processes in a panel subsystem without intervention from a panel processor. The channel scan architecture can provide scan sequence control to enable the panel processor to control the sequence in which individual scans are implemented in the panel subsystem. Type of scans that can be implemented in the panel subsystem can include a spectral analysis scan, touch scan, phantom touch scan, ambient light level scan, proximity scan and temperature scan. | 03-11-2010 |
20100064160 | Circuit Having a Low Power Mode - Embodiments of the invention include an IC that includes a core used for ordinary operation and a thin power circuit. The thin power circuit can be configured to use very little power. The IC can also include a digital interface and a connection thereto. The IC can initiate transition to low power mode during which the core and various I/O pads can be shut down. However, the thin power circuit can be kept powered up. The thin power circuit can monitor the digital interface for a predefined wake up signal. When the wake up signal is detected, the thin power circuit can power up the core and any powered down I/O pads. The thin power circuit can also include a dedicated power on reset (POR) cell. This POR cell can be distinct than other POR cells used for the IC and can be specifically designed to for efficient operation. | 03-11-2010 |
20100164898 | Channel Scan Logic - A device that can autonomously scan a sensor panel is disclosed. Autonomous scanning can be performed by implementing channel scan logic. In one embodiment, channel scan logic carries out many of the functions that a processor would normally undertake, including generating timing sequences and obtaining result data; comparing scan result data against a threshold value (e.g., in an auto-scan mode); generating row count; selecting one or more scanning frequency bands; power management control; and performing an auto-scan routine in a low power mode. | 07-01-2010 |
20100173680 | CHANNEL SCAN LOGIC - A device that can autonomously scan a sensor panel is disclosed. Autonomous scanning can be performed by implementing channel scan logic. In one embodiment, channel scan logic carries out many of the functions that a processor would normally undertake, including generating timing sequences and obtaining result data; comparing scan result data against a threshold value (e.g., in an auto-scan mode); generating row count; selecting one or more scanning frequency bands; power management control; and performing an auto-scan routine in a low power mode. | 07-08-2010 |
20100188356 | CHANNEL SCAN LOGIC - A device that can autonomously scan a sensor panel is disclosed. Autonomous scanning can be performed by implementing channel scan logic. In one embodiment, channel scan logic carries out many of the functions that a processor would normally undertake, including generating timing sequences and obtaining result data; comparing scan result data against a threshold value (e.g., in an auto-scan mode); generating row count; selecting one or more scanning frequency bands; power management control; and performing an auto-scan routine in a low power mode. | 07-29-2010 |
20110025634 | DETECTION OF LOW NOISE FREQUENCIES FOR MULTIPLE FREQUENCY SENSOR PANEL STIMULATION - The identification of low noise stimulation frequencies for detecting and localizing touch events on a touch sensor panel is disclosed. Each of a plurality of sense channels can be coupled to a separate sense line in a touch sensor panel and can have multiple mixers, each mixer using a demodulation frequency of a particular frequency, phase and delay. With no stimulation signal applied to any drive lines in the touch sensor panel, pairs of mixers can demodulate the sum of the output of all sense channels using the in-phase (I) and quadrature (Q) signals of a particular frequency. The demodulated outputs of each mixer pair can be used to calculate the magnitude of the noise at that particular frequency, wherein the lower the magnitude, the lower the noise at that frequency. Several low noise frequencies can be selected for use in a subsequent touch sensor panel scan function. | 02-03-2011 |
20110061947 | Power Management for Touch Controller - Power management for a touch controller is disclosed. The touch controller can include a transmit section for transmitting stimulation signals to an associated touch sensor panel to drive the panel, where the touch controller can selectively adjust the transmit section to reduce power during the transmission. The touch controller can also include a receive section for receiving touch signals resulting from the driving of the panel, where the touch controller can selectively adjust the receive section to reduce power during the receipt of the touch signals. The touch controller can also include a demodulation section for demodulating the received touch signals to obtain touch event results, where the touch controller can selectively adjust the demodulation section to reduce power during the demodulation of the touch signals. The touch controller can also selectively reduce power below present low levels during idle periods. The touch controller can be incorporated into a touch sensitive device. | 03-17-2011 |
20110061948 | Touch Controller with Improved Diagnostics Calibration and Communications Support - A touch controller with improved diagnostics calibration and communication support includes a data capture register configured to sample data from one or a plurality of touch panel sense channels at an output of an analog to digital (A/D) converter. The sampled data is bit packed, and a demodulation waveform is captured, correlated with the sampled data. The contents of the data capture register, including the sampled data and the demodulation waveform, are transferred to a memory configured to create one or more records from the transferred contents. A processor can be used to extract the one or more records captured in the memory to display to a user for diagnostics or calibration. | 03-17-2011 |
20110061949 | MEASURING BODY CAPACITANCE EFFECT IN TOUCH SENSITIVE DEVICE - Measuring an effect of body capacitance in a touch sensitive device is disclosed. This effect can be caused by poor grounding of a user or other objects touching the device or of the device itself. The device can operate in a stray capacitance mode to measure a body capacitance effect and in a normal mode to detect a touch on the device. During the stray capacitance mode, the device can obtain a body capacitance measurement from the device. During the normal mode, the device can obtain a touch measurement from the device. The device can calculate a body capacitance factor based on a ratio between the body capacitance measurement and the touch measurement and use the body capacitance factor to compensate for erroneous or distorted touch output values from the device. Various components of the device can be switchably configured according to the particular mode. | 03-17-2011 |
20110063154 | TOUCH CONTROLLER WITH IMPROVED ANALOG FRONT END - A controller for a touch sensor includes a transimpedance amplifier, and a feedback resistor coupled to an input of the transimpedance amplifier and to an output of the transimpedance amplifier. At least one multiplexor may be coupled to the input of the transimpedance amplifier and configured to multiplex a plurality of analog inputs to one dedicated channel. The controller may further include a bandpass filter coupled to the output of the transimpedance amplifier. The output of the bandpass filter may be input to an anti-aliasing filter, which feeds into an analog to digital converter. Alternatively, the output of the bandpass filter may be input to a sigma-delta analog to digital converter. | 03-17-2011 |
20110063229 | METHOD TO COMPENSATE FOR THE FREQUENCY DEPENDENCE OF SENSE SIGNAL PREPROCESSING - Compensating for the frequency dependence of sense signal preprocessing in preprocessing channel circuitry is provided. The frequency dependence of the preprocessing channels can be modified to change a frequency dependent channel into a frequency independent channel, to change a frequency independent channel into a frequency dependent channel, or to change the frequency dependency characteristics of a frequency dependent channel. Modification of frequency dependency may be accomplished, for example, by modifying certain parameters of a preprocessing channel's components, which can include components for amplifying, filtering, phase adjusting, demodulating, decrypting, for example. A pipelined process may be used to modify the frequency dependency of multiple channels. Compensating for frequency dependencies can have multiple advantages, such as reduction of memory requirements and DIE size. | 03-17-2011 |
20110063993 | Automatic Low Noise Frequency Selection - Automatic low noise frequency selection for a touch sensitive device is disclosed. A low noise stimulation frequency can be automatically selected by device logic without intervention of the device processor to stimulate the device to sense a touch event at the device. The device logic can automatically select a set of low noise frequencies from among various frequencies based on the amount of noise introduced by the device at the various frequencies, where the frequencies with the lower noise amounts can be selected. The device logic can also automatically select a low noise frequency from among the selected set as the low noise stimulation frequency. The device logic can be implemented partially or entirely in hardware. | 03-17-2011 |
20110187677 | SEGMENTED VCOM - Disclosed herein are liquid-crystal display (LCD) touch screens that integrate the touch sensing elements with the display circuitry. The integration may take a variety of forms. Touch sensing elements can be completely implemented within the LCD stackup but outside the not between the color filter plate and the array plate. Alternatively, some touch sensing elements can be between the color filter and array plates with other touch sensing elements not between the plates. In another alternative, all touch sensing elements can be between the color filter and array plates. The latter alternative can include both conventional and in-plane-switching (IPS) LCDs. In some forms, one or more display structures can also have a touch sensing function. Techniques for manufacturing and operating such displays, as well as various devices embodying such displays are also disclosed. | 08-04-2011 |
20110273402 | SAR ADC WITH DYNAMIC INPUT SCALING AND OFFSET ADJUSTMENT - An apparatus for generating an image of touch on or about a touch-sensitive surface comprising a touch panel is disclosed. The touch panel can include a plurality of touch sensors configured for detecting one or more touch events occurring at distinct locations at about the same time. Each touch event can comprise a touching of an object against the touch-sensitive surface. A plurality of receive channels can be coupled to the touch panel for generating values representative of detected touch events. The receive channels can include a charge redistribution successive approximation register digital-to-analog converter (SAR ADC) configured to convert an analog waveform into a digital representation via a binary search and outputting the digital representation to an output register. The SAR ADC architecture can be such that it the dynamic input range can be scaled and offset adjusted. | 11-10-2011 |
20120019467 | SINGLE-CHIP MULTI-STIMULUS SENSOR CONTROLLER - A multi-stimulus controller for a multi-touch sensor is formed on a single integrated circuit (single-chip). The multi-stimulus controller includes a transmit oscillator, a transmit signal section that generates a plurality of drive signals based on a frequency of the transmit oscillator, a plurality of transmit channels that transmit the drive signals simultaneously to drive the multi-touch sensor, a receive channel that receives a sense signal resulting from the driving of the multi-touch sensor, a receive oscillator, and a demodulation section that demodulates the received sense signal based on a frequency of the receive oscillator to obtain sensing results, the demodulation section including a demodulator and a vector operator. | 01-26-2012 |
20120098778 | CHANNEL SCAN LOGIC - A device that can autonomously scan a sensor panel is disclosed. Autonomous scanning can be performed by implementing channel scan logic. In one embodiment, channel scan logic carries out many of the functions that a processor would normally undertake, including generating timing sequences and obtaining result data; comparing scan result data against a threshold value (e.g., in an auto-scan mode); generating row count; selecting one or more scanning frequency bands; power management control; and performing an auto-scan routine in a low power mode. | 04-26-2012 |
20120113064 | DOWNSAMPLING DATA FOR CROSSTALK COMPENSATION - A touch sensitive device having circuitry to compensate for crosstalk from the device display to the device touch sensor panel is disclosed. The crosstalk compensation circuitry can include a downsampler and a crosstalk compensator. The downsampler can downsample a display image to a manageable size for transmission and processing and can then send the downsampled image to the crosstalk compensator so as to provide information about the display operation that can be used to estimate the expected amount of crosstalk caused by the display. The crosstalk compensator can estimate the amount of crosstalk based on the downsampled image and can then compensate a touch image captured by the touch sensor panel for the estimated amount, the touch image being indicative of a touch or hover event at the panel. | 05-10-2012 |
20120139846 | NOISE REDUCTION FOR TOUCH CONTROLLER - A touch controller having noise reduction circuitry is disclosed. The touch controller can include a transmit section for generating stimulation signals to drive a touch display to sense a touch or hover event. The touch controller can also include a receive section for processing touch signals from the touch display indicative of the touch or hover event. The touch controller can reduce noise introduced into the stimulation signals and propagated through the touch display into the touch signals, thereby interfering with touch and hover sensing. To reduce the noise, the transmit section's noise reduction circuitry can isolate and subtract the noise from the stimulation signals. In addition or alternatively, the receive section's noise reduction circuitry can isolate and subtract the noise from the touch signals. In addition or alternatively, the transmit section's noise reduction circuitry can isolate and subtract some of the noise from the stimulation signals, while the receive section's noise reduction circuitry to isolate and subtract the remainder of the noise from the touch signals. In additional to a touch display, the touch controller can be similarly employed with a touch sensor panel. | 06-07-2012 |
20120139865 | TOUCH DEVICE COMMUNICATION - A system for data communication between a plurality of touch devices is disclosed. The system can include a first touch device having a first touch surface, and at least one other touch device having at least one other touch surface. The first touch device and the at least one other touch device can include a touch controller detecting communications coupling between the first touch surface and the least one other touch surface. The first touch device and the at least one other touch device can include a communication unit communicating data between the first touch device and the at least one other touch device, via the first touch surface and the at least one other touch surface, when the communications coupling is detected. The communications coupling can be detected when a coupling conduit contacts, or is proximate to, the first touch surface and at least one other touch surface. | 06-07-2012 |
20120157167 | MULTI-TOUCH AUTO SCANNING - A system and method for autonomously scanning a sensor panel device, is disclosed. A sensor panel processor can be disabled after a first predetermined amount of time has elapsed without the sensor panel device sensing any events. One or more system clocks can also be disabled to conserve power. While the processor and one or more system clocks are disabled, the sensor panel device can periodically autonomously scan the sensor panel for touch activity. If one or more results from the autonomous scans exceed a threshold, the sensor panel device re-enables the processor and one or more clocks to actively scan the sensor panel. If the threshold is not exceeded, then the sensor panel device continues to periodically autonomously scan the sensor panel without intervention from the processor. The sensor panel device can periodically perform calibration functions to account for any drift that may be present in the system. | 06-21-2012 |
20120162129 | MULTI-TOUCH AUTO SCANNING - A system and method for autonomously scanning a sensor panel device is disclosed. A sensor panel processor can be disabled after a first predetermined amount of time has elapsed without the sensor panel device sensing any events. One or more system clocks can also be disabled to conserve power. While the processor and one or more system clocks are disabled, the sensor panel device can periodically autonomously scan the sensor panel for touch activity. If one or more results from the autonomous scans exceed a threshold, the sensor panel device re-enables the processor and one or more clocks to actively scan the sensor panel. If the threshold is not exceeded, the sensor panel device continues to periodically autonomously scan the sensor panel without intervention from the processor. The sensor panel device can periodically perform calibration functions to account for any drift that may be present in the system. | 06-28-2012 |
20120182251 | DISPLAY TO TOUCH CROSSTALK COMPENSATION - A touch sensitive display capable of compensating for crosstalk in the display is disclosed. Crosstalk in display components can be reduced, eliminated, or otherwise compensated for by reducing or eliminating parasitic capacitances that cause the crosstalk. To do so, gate voltages to the display components, such as thin film transistors (TFTs), that introduce the parasitic capacitances can be reduced or otherwise adjusted. In one approach, the gate voltage can be set at multiple different low levels to generate respective sets of touch signals having different amounts of crosstalk. The different crosstalk amounts can then be used to determine and compensate for the crosstalk in the touch signals. In another approach, gate voltage can be modulated between multiple different low levels to push crosstalk out of band with the generated touch signals. The out-of-band crosstalk can then be used to compensate for the crosstalk in the touch signals. | 07-19-2012 |
20120194477 | INTERACTIVE HOLOGRAPHIC DISPLAY DEVICE - A display apparatus configured to produce an interactive three-dimensional holographic image is disclosed. The display apparatus can include one or more coherent light sources configured to produce one or more beams, based on obtained image data of an object to display, and a lens assembly configured to direct the one or more beams to form a holographic image of the object. The lens assembly can include a collimating lens and a lens capable of beam steering one or more beams, including a micro-lens assembly with at least one micro-lens configured to generate a plurality of beams associated with a plurality of desired viewing angles. One or more optical sensors can be configured to obtain information regarding whether an interactive device interrupts the one or more beams, and a processor unit can determine a location of the interactive device with respect to the holographic image. | 08-02-2012 |
20120268423 | TOUCH SCREEN LIQUID CRYSTAL DISPLAY - Disclosed herein are liquid-crystal display (LCD) touch screens that integrate the touch sensing elements with the display circuitry. The integration may take a variety of forms. Touch sensing elements can be completely implemented within the LCD stackup but outside the not between the color filter plate and the array plate. Alternatively, some touch sensing elements can be between the color filter and array plates with other touch sensing elements not between the plates. In another alternative, all touch sensing elements can be between the color filter and array plates. The latter alternative can include both conventional and in-plane-switching (IPS) LCDs. In some forms, one or more display structures can also have a touch sensing function. Techniques for manufacturing and operating such displays, as well as various devices embodying such displays are also disclosed. | 10-25-2012 |
20120280932 | SCAN SEQUENCE GENERATOR - A sensor panel device that can generate and use a stimulus signal having multiple different waveforms for detecting events on or near the sensor panel is disclosed. Among other things, such a stimulus signal can be used to reject environmental noise present in the device. In some embodiments, the stimulus signal has multiple waveforms having different frequencies. Logic circuitry can generate representative values from output of the different waveforms applied to one or more sensing nodes in the sensor panel device. From the representative values, a final value can be generated that represents whether an event occurred at or near the one or more sensing nodes. | 11-08-2012 |
20130069904 | NOISE REJECTION CIRCUIT FOR TOUCH SENSITIVE DISPLAY - A noise rejection circuit for a touch sensitive display is disclosed. The noise rejection circuit can reject noise introduced by the touch sensitive display's display device into its touch panel. The noise rejection circuit can be integrated into the touch circuitry of the touch sensitive display and can include a resistor to sense the noise and an amplifier to isolate the sensed noise for rejection. | 03-21-2013 |
20130069905 | CONCURRENT TOUCH AND NEGATIVE PIXEL SCAN - A concurrent touch and negative pixel scan performed at a touch panel is disclosed. The concurrent scan can include sensing an object proximate to the touch panel and sensing a negative pixel effect, based the object's grounding condition, at the touch panel, at the same time. As a result, sense signals indicative of the proximity of the object and coupling signals indicative of the negative pixel effect's magnitude can be captured concurrently. Because the negative pixel effect can cause errors or distortions in the sense signals, the coupling signals can be used to compensate the sense signals for the negative pixel effect. | 03-21-2013 |
20130076646 | FORCE SENSOR INTERFACE FOR TOUCH CONTROLLER - A force sensor interface in a touch controller of a touch sensitive device is disclosed. The force sensor interface can couple to touch circuitry to integrate one or more force sensors with touch sensors of the device. The force sensor interface can include one portion to transmit stimulation signals generated by the touch circuitry to the force sensors to drive the sensors. The interface can also include another portion to receive force signals, indicative of a force applied to the device, from the force sensors for processing by the touch circuitry. The device can use the touch circuitry to concurrently and seamlessly operate both the force sensors and the touch sensors. | 03-28-2013 |
20130076648 | POWER MANAGEMENT FOR INTEGRATED TOUCH SCREENS - Reducing or eliminating the effects of noise that can be generated by a power system of a touch screen device, such as a gate line voltage system that applies voltage to gate lines of the touch screen, is provided. In one example, a power supply, such as a charge pump, can be disabled during active touch sensing, such that noise from the charge pump is not generated during touch sensing. In some examples, a voltage regulator can help to maintain the gate voltage level at or above a desired threshold. In some cases, noise entering the touch sensing system can have a lasting effect on noise-sensitive components, even after the noise source is disabled. In these cases, a post-noise stabilizing system can be included to stabilize, reset, etc., noise-sensitive components of the touch sensing system, which can help to reduce or eliminate the lasting effect of noise. | 03-28-2013 |
20130207906 | QUADRATURE DEMODULATION FOR TOUCH SENSITIVE DEVICES - Demodulation circuits and processes for demodulating touch signals from a touch sensor using the demodulation circuits are provided. The demodulation circuits can include circuitry configured to determine an adjustable phase delay based at least in part on a quadrature component of the touch signal or the phase-adjusted touch signal. The demodulation circuit can further include circuitry for applying the adjustable phase delay to the touch signal to compensate for phase delays in the touch signal caused by the touch sensor and/or other components. The demodulation circuit can dynamically change the adjustable phase delay to compensate for time-varying phase delays caused by the touch sensor and/or other components. | 08-15-2013 |
20130265242 | TOUCH SENSOR COMMON MODE NOISE RECOVERY - A touch sensor panel configured to minimize the effect on touch or proximity event detection caused by a common mode noise event. The touch sensor panel includes circuitry that works to minimize the amount of time that the touch sensor panel is unable to accurately sense touch and proximity events due to a common mode noise event. The touch sensor panel can also re-acquire data that was collected during the time that the sensor panel was unable to accurately detect touch and proximity events, when a common mode noise event is detected. | 10-10-2013 |
20130271410 | TOUCH DETECTION USING MULTIPLE SIMULTANEOUS FREQUENCIES - The use of multiple stimulation frequencies and phases to generate an image of touch on a touch sensor panel is disclosed. Each of a plurality of sense channels can be coupled to a column in a touch sensor panel and can have multiple mixers. Each mixer in the sense channel can utilize a circuit capable generating a demodulation frequency of a particular frequency. At each of multiple steps, various phases of selected frequencies can be used to simultaneously stimulate the rows of the touch sensor panel, and the multiple mixers in each sense channel can be configured to demodulate the signal received from the column connected to each sense channel using the selected frequencies. After all steps have been completed, the demodulated signals from the multiple mixers can be used in calculations to determine an image of touch for the touch sensor panel at each frequency. | 10-17-2013 |
20140028634 | STYLUS DEVICE - Styluses capable of generating stylus stimulation signals and touch sensitive devices capable of receiving stylus stimulation signals are disclosed. In one example, a stylus can receive a stimulation signal from a touch sensor of a touch sensitive device and generate a stylus stimulation signal by changing an amplitude or frequency of the received stimulation signal. The stylus can transmit the stylus stimulation signal back into the touch sensor of the touch sensitive device. The touch sensor can generate a touch signal based on the device's own stimulation signals and the stylus stimulation signal. The touch sensitive device can process the touch signal to determine a location of the stylus on the touch sensor. The stylus can include a force sensor to detect an amount of force applied to a tip of the stylus. The stylus stimulation signal can be modulated based on the force detected by the force sensor. | 01-30-2014 |
20140028635 | MODULAR STYLUS DEVICE - Modular styluses having a base module an expansion module are disclosed. The base module can include a stylus tip, a stylus stimulation signal circuit capable of generating a stimulation signal, a processor for controlling the stylus stimulation signal circuit, and a connection interface for selectively connecting the base module to an expansion module. The expansion module can include a power source for providing power to the stylus stimulation signal circuit and the processor. The expansion module can also include one or more of a power source, camera, audio recorder, communication circuit, gyroscope, accelerometer, laser pointer, projector, or the like. The projector can be used to display an image on a surface and to allow a user to edit a document by moving the stylus across the projected image. | 01-30-2014 |
20140043293 | SINGLE-CHIP MULTI-STIMULUS SENSOR CONTROLLER - A multi-stimulus controller for a multi-touch sensor is formed on a single integrated circuit (single-chip). The multi-stimulus controller includes a transmit oscillator, a transmit signal section that generates a plurality of drive signals based on a frequency of the transmit oscillator, a plurality of transmit channels that transmit the drive signals simultaneously to drive the multi-touch sensor, a receive channel that receives a sense signal resulting from the driving of the multi-touch sensor, a receive oscillator, and a demodulation section that demodulates the received sense signal based on a frequency of the receive oscillator to obtain sensing results, the demodulation section including a demodulator and a vector operator. | 02-13-2014 |
20140049497 | TOUCH CONTROLLER WITH IMPROVED DIAGNOSTICS CALIBRATION AND COMMUNICATIONS SUPPORT - A touch controller with improved diagnostics calibration and communication support includes a data capture register configured to sample data from one or a plurality of touch panel sense channels at an output of an analog to digital (A/D) converter. The sampled data is bit packed, and a demodulation waveform is captured, correlated with the sampled data. The contents of the data capture register, including the sampled data and the demodulation waveform, are transferred to a memory configured to create one or more records from the transferred contents. A processor can be used to extract the one or more records captured in the memory to display to a user for diagnostics or calibration. | 02-20-2014 |
20140092063 | SCAN SEQUENCE GENERATOR - A sensor panel device that can generate and use a stimulus signal having multiple different waveforms for detecting events on or near the sensor panel is disclosed. Among other things, such a stimulus signal can be used to reject environmental noise present in the device. In some embodiments, the stimulus signal has multiple waveforms having different frequencies. Logic circuitry can generate representative values from output of the different waveforms applied to one or more sensing nodes in the sensor panel device. From the representative values, a final value can be generated that represents whether an event occurred at or near the one or more sensing nodes. | 04-03-2014 |
20140139457 | INTEGRATED DISPLAY AND TOUCH SCREEN - Liquid crystal display (LCD) touch screens integrate touch sensing elements with display circuitry and may include in-plane-switching (IPS) LCDs. A method of operating the integrated touch sensing elements with the display circuitry includes dividing touch-sensing circuitry of the touch screen into a plurality of drive segments, each drive segment overlapping one or more display rows; updating the display at a predetermined refresh rate; stimulating the plurality of drive segments at a predetermined scan rate; and changing the sequence of stimulating the plurality of drive segments as required to prevent simultaneously stimulating a drive segment that overlaps a display row currently being updated. | 05-22-2014 |
20140152619 | TOUCH SCREEN LIQUID CRYSTAL DISPLAY - Disclosed herein are liquid-crystal display (LCD) touch screens that integrate the touch sensing elements with the display circuitry. The integration may take a variety of forms. Touch sensing elements can be completely implemented within the LCD stackup but outside the not between the color filter plate and the array plate. Alternatively, some touch sensing elements can be between the color filter and array plates with other touch sensing elements not between the plates. In another alternative, all touch sensing elements can be between the color filter and array plates. The latter alternative can include both conventional and in-plane-switching (IPS) LCDs. In some forms, one or more display structures can also have a touch sensing function. Techniques for manufacturing and operating such displays, as well as various devices embodying such displays are also disclosed. | 06-05-2014 |
20140267086 | DYNAMIC CROSS-TALK MITIGATION FOR INTEGRATED TOUCH SCREENS - A touch input device configured to mitigate the effects of dynamic cross talk noise is provided. The touch input device can dither an effective resistance of a plurality of gate lines proximal to the touch sensor panel in order to determine if a phase of a touch signal demodulator needs to be adjusted. | 09-18-2014 |
20140267087 | DYNAMIC CROSS-TALK MITIGATION FOR INTEGRATED TOUCH SCREENS - A touch input device configured to mitigate the effects of dynamic cross talk noise is provided. The touch input device can dither an effective resistance of a plurality of gate lines proximal to the touch sensor panel in order to determine if a phase of a touch signal demodulator needs to be adjusted. | 09-18-2014 |