Abstract: A circuit for switching an LCD between display and touch modes is disclosed. The circuit can include one or more switches configured to switch one or more drive, sense, and data lines in LCD pixels according to the mode. During touch mode, the circuit switches can be configured to switch one or more drive lines to receive stimulation signals, one or more sense lines to transmit touch signals, and one or more data lines to transmit residual data signals. During display mode, the circuit switches can be configured to switch one or more drive lines and sense lines to receive common voltage signals and one or more data lines to receive data signals. The circuit can be formed around the border of the LCD chip or partially or fully on a separate chip.

Abstract: Touch screens with more compact border regions can include an active area that includes touch sensing circuitry including drive lines, and a border region around the active area. The border region can include an area of sealant deposited on conductive lines, and transistor circuitry, such as gate drivers, between the active area and the sealant. The conductive lines can extend from the sealant to the active area without electrically connecting to the transistor circuitry. The conductive lines can have equal impedances and can connect the drive lines to a touch controller off of the touch screen. A set of drive signal characteristics for the drive lines can be obtained by determining a transfer function associated with each drive line, obtaining an inverse of each transfer function, and applying a set of individual sense signal characteristics to the inverse transfer functions to obtain the corresponding set of drive signal characteristics.

Abstract: A touch panel electrode structure for user grounding correction in a touch panel is discloses. The electrode structure can include an array of electrodes for sensing a touch at the panel, and multiple jumpers for selectively coupling groups of the electrodes together to form electrode rows and columns that cross each other. In some examples, the array can have a linear configuration and can form the rows and columns by coupling diagonally adjacent electrodes using the jumpers in a zigzag pattern, or the array can have a diamond configuration and can form the rows and columns by coupling linearly adjacent electrodes using the jumpers in a linear pattern. In various examples, each electrode can have a solid structure with a square shape, a reduced area with an outer electrode and a physically separate center electrode, a hollow center, or a solid structure with a hexagonal shape.

Abstract: An integrated touch sensitive display is provided. The integrated touch sensitive display can include rows and columns of touch electrodes. Various modulation techniques can be applied to one or more of the touch electrodes to allow sense circuitry to individually measure a capacitance associated with each of the touch electrodes. The capacitances can be used to determine a location and/or amount of touch or hover events at or near the integrated touch sensitive display.

Abstract: Touch sensitive displays are disclosed that can include circuitry that is segmented into multiple portions that can be independently operated. Touch sensitive display circuitry can be split in half with an upper portion and a lower portion that can each be independently operated. The separate circuitry portions can be used for performing display operations and for performing touch sensing operations. Display operations can be performed in one portion of the display while touch sensing operations are simultaneously performed in another portion of the display. Periodically, the operation being performed in a given portion of the display can be switched so as to alternatingly update that portion of the display and sense touch events in that region.

Abstract: A touch panel capable of measuring both mutual and self capacitance is disclosed. The touch panel can measure self capacitance and mutual capacitance at various electrode patterns and, based on the self capacitance measurements, the mutual capacitance measurements, or both, calculate a touch signal indicative of an object touching or hovering over the touch panel. In some examples, the measurements can also be used to determine a correction factor, indicative of an adverse condition at the touch panel, and the correction factor used to correct the touch signal for the adverse condition. The touch panel can have a row-column electrode pattern or a pixelated electrode pattern.

Abstract: A fingerprint sensor is incorporated in a display stack in an electronic device. A single fingerprint can be captured at one time at a single pre-defined fixed location on a display. Alternatively, a single fingerprint can be acquired at one time at any location on a display. Alternatively, multiple touches on the display can be acquired substantially simultaneously where only one fingerprint is captured at a time or where all of the fingerprints are acquired at the same time. The fingerprint sensor can be implemented as an integrated circuit connected to a bottom surface of a cover sheet, near the bottom surface of the cover sheet, or connected to a top surface of a display. Alternatively, the fingerprint sensor can be implemented as a full panel fingerprint sensor.

Abstract: A touch controller that can configure touch circuitry according to a scan plan, which can define a sequence of scan events to be performed on a touch panel is disclosed. The touch controller can include a configurable transmit section to generate stimulation signals to drive the panel, a configurable receive section to receive and process touch signals from the panel, and a configurable memory to store the touch signals. The touch controller can also include a programmable scan engine to configure the transmit section, the receive section, and the memory according to the scan plan. The touch controller advantageously provides more robust and flexible touch circuitry to handle various types of touch events at the panel. An active stylus that can generate stimulation signals that can be detected by the touch controller during various touch events at the panel is also disclosed.

Abstract: Displaying an image on a display screen is provided by periodically changing the scanning order in which rows of sub-pixels of the display screen are scanned. One scanning order can be selected to scan the rows in the update of a first image frame of the display, and then a different scanning order can be selected to scan the rows in the update of a second image frame. Particular scanning orders can be selected in order to reduce or eliminate the appearance of visual artifacts by changing the location of the visual artifacts across multiple image frames. For example, different scanning orders that result in visual artifacts at different positions on the display screen can be used, and the selection of scanning order can periodically change among the different scanning orders such that the position of the visual artifacts changes periodically during the updating of multiple image frames.

Abstract: A circuit for switching an LCD between display and touch modes is disclosed. The circuit can include one or more switches configured to switch one or more drive, sense, and data lines in LCD pixels according to the mode. During touch mode, the circuit switches can be configured to switch one or more drive lines to receive stimulation signals, one or more sense lines to transmit touch signals, and one or more data lines to transmit residual data signals. During display mode, the circuit switches can be configured to switch one or more drive lines and sense lines to receive common voltage signals and one or more data lines to receive data signals. The circuit can be formed around the border of the LCD chip or partially or fully on a separate chip.

Abstract: A display having data lines that can be configured between a display mode and a touch mode is disclosed. The display can have sense regions for sensing a touch or near touch on the display during the touch mode. These same regions can display graphics or data on the display during the display mode. During display mode, the data lines in the sense regions can be configured to couple to display circuitry in order to receive data signals from the circuitry for displaying. During touch mode, the data lines in the sense regions can be configured to couple to corresponding sense lines in the regions, which in turn can couple to touch circuitry, in order to transmit touch signals to the circuitry for sensing a touch or near touch. Alternatively, during touch mode, the data lines in the sense regions can be configured to couple to ground in order to transmit residual data signals to ground for discarding.

Abstract: 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.

Abstract: A touch screen to reduce touch pixel coupling. In some examples, the touch screen can include a first display pixel and a second display pixel in a row of display pixels, where the first display pixel can be configurable to be decoupled from the second display pixel during at least a touch sensing phase of the touch screen. In some examples, the touch screen can include a display pixel having a first and a second transistor, where the second transistor can be electrically connected to a gate terminal of the first transistor, and can be diode-connected. In some examples, the touch screen can include two display pixels, each display pixel having two transistors, where two of the transistors can be electrically connected to a first gate line, and the remaining two transistors can be individually electrically connected to a second and third gate line, respectively.

Abstract: A display may be provided with integral touch functionality. The display may include a common electrode layer having row electrodes arranged in rows and column electrodes interposed between the row electrodes of each row. The row electrodes may be electrically coupled by conductive paths. The row and column electrodes may be coupled to touch sensor circuitry that uses the row and column electrodes to detect touch events. Each electrode of the common electrode layer may cover a respective portion of an array of pixels. Each pixel of the display may have a respective aperture. The conductive paths that electrically couple row electrodes of the common electrode layer may cover or otherwise block some light from passing through pixels, resulting in reduced apertures. Dummy structures may be provided for other pixels that modify the apertures of the other pixels to match the reduced apertures associated with the conductive paths.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: Compensation of pixels included in a touch sensor panel that generate erroneous readings (so called “negative pixels”) due to a poor grounding condition of the object touching the touch sensor panel is disclosed herein. To compensate for the erroneous readings, sense lines of the touch sensor panel can include reverse driving circuits to facilitate calculation of an object-to-ground capacitance. If the calculated object-to-ground capacitance indicates the presence of a poor grounding condition, then the object-to-ground capacitance and detected pixel touch output values are used to estimate new pixel touch output values that are used instead of the detected pixel touch output values to determine touch event(s).

Abstract: A display having data lines that can be configured between a display mode and a touch mode is disclosed. The display can have sense regions for sensing a touch or near touch on the display during the touch mode. These same regions can display graphics or data on the display during the display mode. During display mode, the data lines in the sense regions can be configured to couple to display circuitry in order to receive data signals from the circuitry for displaying. During touch mode, the data lines in the sense regions can be configured to couple to corresponding sense lines in the regions, which in turn can couple to touch circuitry, in order to transmit touch signals to the circuitry for sensing a touch or near touch. Alternatively, during touch mode, the data lines in the sense regions can be configured to couple to ground in order to transmit residual data signals to ground for discarding.

Abstract: Displays with integrated touch sensing circuitry are provided. An integrated touch screen can include multi-function circuit elements that form part of the display circuitry of the display system that generates an image on the display, and also form part of the touch sensing circuitry of a touch sensing system that senses one or more touches on or near the display. The multi-function circuit elements can be, for example, capacitors in display pixels of an LCD that are configured to operate as display circuitry in the display system, and that may also be configured to operate as touch circuitry of the touch sensing system. For example, one or more circuit elements of the display pixel stackup can form a conductive portion of the touch sensing system, such as a charge collector, which can be operated with switches and conductive lines to sense touch.