Abstract: Apparatus (22) for processing signals from a touch panel (10) is described. The touch panel (10) includes a layer of piezoelectric material (16) disposed between a plurality of sensing electrodes (14, 20) and at least one common electrode (15). The apparatus (22) includes a first circuit (23) for connection to the plurality of sensing electrodes (14, 20). The first circuit (23) is configured to generate a plurality of first pressure signals (29). Each first pressure signal (29) corresponds to one or more sensing electrodes (14, 20) and is indicative of a pressure acting on the touch panel (10) proximate to the corresponding one or more sensing electrodes (14, 20). The apparatus (22) also includes a second circuit (24) for connection to the at least one common electrode (15). The second circuit (24) is configured to generate a second pressure signal (30) indicative of a total pressure applied to the touch panel (10).

Abstract: A touchscreen system for generating localised haptic excitations includes a touchscreen panel for measuring force and/or capacitance. The touchscreen system includes one or more first piezoelectric transducers arranged to generate excitations in the touchscreen panel along a first line. The touchscreen system includes one or more second piezoelectric transducers arranged to generate excitations in the touchscreen panel along a second line which is inclined to the first line at an angle. The touchscreen system includes a pressure and/or capacitance sensing module connected to the touchscreen panel and configured to measure a force and/or capacitance from the touchscreen panel.

Abstract: A method for processing signals from a touchscreen panel includes obtaining a partial frame by sampling parts of a frame from a touch panel which comprises an array of sensor areas (step S1). The method also includes generating, based on the partial frame, a new frame which comprises estimates of the un-sampled parts (step S2). The method also includes determining whether at least one touch event is present in the new frame (step S3), and upon a positive determination, for each touch event, determining a location of the touch event in the new frame and obtaining a sub-frame by sampling a region of a subsequent frame from the touch panel frame at and around the location (step S4). The method also includes outputting touch information based on one or more sub-frames (step S7).

Abstract: A pressure sensing architecture for use with liquid crystal (LC), organic light emitting diode (OLED), electrophoretic, or other similarly fabricated displays. The described architecture includes a bottom TFT structure and a top structure with color filter material, and with liquid crystal, electrophoretic or OLED material provided in between. A piezoelectric or equivalent material is provided within the display assembly. Transmitting and receiving electrodes can be used to electrically bias the piezoelectric or equivalent material, which provides an analog electrical signal in response to incident touch pressure.

Abstract: A device (48) for combined capacitance and pressure measurements includes a number of first input/output terminals for a projected capacitance touch panel, wherein the projected capacitance touch panel includes a layer of piezoelectric material disposed between a plurality of first electrodes and at least one second electrode. The device also includes a plurality of second input/output terminals for a capacitive touch controller. The device also includes a plurality of separation stages, each separation stage connecting at least one first input/output terminal to a corresponding second input/output terminal, and each separation stage including a first frequency-dependent filter for filtering signals between first and second input/output terminals.

Abstract: An apparatus for combined capacitance and pressure sensing is described. The apparatus includes a multiplexer (75) having a plurality of inputs (76) and an output (F), a touch panel (29), and a front end module (3). The touch panel includes a layer structure (5; FIG. 15) comprising one or more layers, each extending perpendicularly to a thickness direction, the one or more layers including a layer of piezoelectric material (10; FIG. 15), the layer structure having first (6) and second (7; FIG. 15) opposite faces, and the layer(s) arranged between the first and second faces such that the thickness direction of each layer is perpendicular to the first and second faces. The touch panel also includes a plurality of first electrodes (8) disposed on the first face, each first electrode connected to a respective input of the multiplexer. The touch panel also includes at least one second electrode (9) disposed on the second face.

Abstract: An apparatus for combined capacitance and pressure sensing is described. The apparatus includes a multiplexer (75) having a plurality of inputs (76) and an output (F), a touch panel (29), and a front end module (3). The touch panel includes a layer structure (5; FIG. 15) comprising one or more layers, each extending perpendicularly to a thickness direction, the one or more layers including a layer of piezoelectric material (10; FIG. 15), the layer structure having first (6) and second (7; FIG. 15) opposite faces, and the layer(s) arranged between the first and second faces such that the thickness direction of each layer is perpendicular to the first and second faces. The touch panel also includes a plurality of first electrodes (8) disposed on the first face, each first electrode connected to a respective input of the multiplexer. The touch panel also includes at least one second electrode (9) disposed on the second face.

Abstract: A method for processing signals from a touchscreen panel includes obtaining a partial frame by sampling parts of a frame from a touch panel which comprises an array of sensor areas (step S1). The method also includes generating, based on the partial frame, a new frame which comprises estimates of the un-sampled parts (step S2). The method also includes determining whether at least one touch event is present in the new frame (step S3), and upon a positive determination, for each touch event, determining a location of the touch event in the new frame and obtaining a sub-frame by sampling a region of a subsequent frame from the touch panel frame at and around the location (step S4). The method also includes outputting touch information based on one or more sub-frames (step S7).

Abstract: A device (48) for combined capacitance and pressure measurements includes a number of first input/output terminals for a projected capacitance touch panel, wherein the projected capacitance touch panel includes a layer of piezoelectric material disposed between a plurality of first electrodes and at least one second electrode. The device also includes a plurality of second input/output terminals for a capacitive touch controller. The device also includes a plurality of separation stages, each separation stage connecting at least one first input/output terminal to a corresponding second input/output terminal, and each separation stage including a first frequency-dependent filter for filtering signals between first and second input/output terminals.

Abstract: A device for combined capacitance and pressure measurements includes a plurality of first input/output terminals for a projected capacitance touch panel wherein the projected capacitance touch panel includes a layer of piezoelectric material disposed between a plurality of sensing electrodes and a common electrode. The device also includes a plurality of second input/output terminals for a capacitive touch controller. The device also includes a plurality of separation stages, each separation stage connecting one first input/output terminal to a corresponding second input/output terminal, and each separation stage includes a first frequency-dependent filter for filtering signals between respective first and second input/output terminals.

Abstract: Switching of power modes for touch screens is disclosed. In example embodiments a touch detect mode may be activated for touchscreen operation. The touchscreen may be a projected capacitance screen that includes force sensing based on piezo electric sensors. The touch detect mode may be a low power mode in which at least one channel, but fewer than all channels of the touch screen are monitored. When is determined that a touch event has occurred a switch to a scan mode for touchscreen operation may be performed. Scan mode may be a higher power mode in which all channels of the touch screen are scanned at least for position sensing. The touch detect mode monitoring may be implemented by monitoring the total charge on the at least one channel and providing a voltage signal. When the voltage signal meets predetermined criteria an indication of a touch event may be generated.

Abstract: A method is described including receiving (S3) a first array of values obtained from measuring an array of touch panel sensor areas (FIG. 4; In,m). The method also includes generating (S4) a second array of values based on subtracting a reference array of values from the first array of values. The method also includes determining (S5) presence of at least one touch event in dependence upon the second array of value and, upon a negative determination (S8) generating a new reference array based on exponential smoothing of the reference array and the first array using a weighting factor, wherein the weighting factor is zero, and storing the new reference matrix and, upon a positive determination (S6) outputting the second array (FIG. 9).