Abstract: One embodiment provides a capacitive sensor for determining the presence of an object, such as a user's finger or a stylus. The sensor includes a substrate on which electrodes are deposited. A resistive drive electrode is arranged on one side of the substrate and a resistive sense electrode is arranged on the other side of the substrate. A shorting connection connects between two locations on one of the electrodes. The electrodes are connected to respective drive and sense channels.

Abstract: In one embodiment, a sensor includes a substrate; multiple interconnected sense elements arranged in a first direction on a surface of the substrate; and first interconnected drive elements arranged on a surface of the substrate in the first direction. Each respective one of the first interconnected drive elements are located adjacent to and between respective ones of the sense elements to form first sets of sense and drive elements alternating in the first direction. The sensor also includes second interconnected drive elements arranged on a surface of the substrate in a second direction. Each respective one of the second interconnected drive elements are located between respective ones of the sense elements to form second sets of sense and drive elements alternating in the second direction.

Abstract: In one embodiment, a method includes receiving two or more output signals responsive to two or more capacitive couplings. Each of the capacitive couplings has occurred between a pointing object and one of two or more sensing areas within a sensing region, and each of the sensing areas has a position within the sensing region. The method includes, if two or more of the output signals each have an output-signal level that exceeds a predefined activation level, then selecting a particular one of the sensing areas with output-signal levels exceeding the predefined activation level as an intended one of the sensing areas based on a predefined ranking scheme that takes into account the positions of the sensing areas within the sensing region.

Abstract: An apparatus for controlling functions of an appliance is described having a touch-sensitive control panel resistant to accidental activation. The touch-sensitive panel has a plurality of proximity sensor areas which may be selected by a user wishing to activate associated functions of the appliance. Driver circuitry coupled to the sensor areas is operable to output detection signals to a controller in response to a user selecting ones of the sensor areas. The controller is configured to activate functions of the appliance in response to these detection signals. For one or more functions of the appliance, for example a switching on function, the controller is configured to only activate the function when a user makes a pre-determined combination of at least two selections from the plurality of sensor areas. This reduces the chances of potentially dangerous functions being activated inadvertently and can further help a designer to provide an intuitive and uncluttered appearance to the control panel.

Abstract: A capacitive touch sensor providing an automatic switch-off function for an apparatus in which the sensor is incorporated is provided. The sensor includes a sensing element coupled to a capacitance measurement circuit for measuring the capacitance of the sensing element. A control circuit is operable to determine from the capacitance measurement whether an object is in proximity with the sensor. The determined presence of an object may he used to toggle a function of the apparatus. Furthermore, when it is determined that an object has not been in proximity with the sensor for a predetermined time duration, an output signal for switching off the apparatus is provided. The predetermined time duration may be selected from a number of predefined time durations, or may be programmed using a resistor-capacitor network. Pulses may be applied to the control circuit to override features of the automatic switch-off functionality.

Abstract: Methods and apparatus related to a sensor are discussed herein. The sensor can include a sensing element having a sensing path, the sensing element coupled to a sensing channel, and a processor configured to interpret a signal generated by the sensing channel indicative of a capacitance between the sensing path and a system ground. The processor can have a first mode configured to set a parameter to a desired value. The desired value can be related to a first position of an object sensed along the sensing path and a range of parameter values mapped to a length of the sensing path. A second mode can adjust the parameter based on a displacement of the object along the sensing path.

Abstract: The invention relates to an energy saving headset that comprises a power management unit operable to reduce the power consumption of the headset when a user is not present. The power management unit uses capacitive sensing to detect the presence of the user. Capacitive sensing is advantageous since it provides a flexible and reliable sensor that can accurately detect the presence or absence of a user either by detecting user proximity or user contact. Moreover, in various embodiments, the sensitivity of a capacitive sensor may be adjusted to account for user movement or changes in environmental conditions, such as, for example, the presence of water, or sweat, on the headset to further improve sensing reliability. The invention further relates to headsets using user presence signals based on capacitive sensing to control other functions of the headset or to control external devices to which the headset is connected, either wirelessly or by wires.

Abstract: A touchscreen display assembly has a substrate and a plurality of electrodes distributed across at least an active area of the substrate. At least one of the electrodes comprises a group of redundant electrode lines electrically coupled to an external electrical circuit connection and further coupled to one another remote from the external electrical circuit connection.

Abstract: A touchscreen includes touchscreen electrode elements distributed across an active area of a substrate, and the touchscreen overlays a display. The touchscreen electrode elements are configured to avoid creating moiré patterns between the display and the touchscreen, such as angled, wavy, zig-zag, or randomized lines. In a further example, the electrodes form a mesh pattern configured to avoid moiré patterns.

Abstract: A controller includes drive circuitry to drive one target drive electrode of a touch sensitive device with a series of predetermined phase pulses and to drive at least one other drive electrode of the touch sensitive device with a corresponding series of out-of-phase pulses. Sense circuitry receives signal transferred to sense electrodes from the drive electrodes of the touch sensitive device. The received signal is responsive to one or more touches on the touch sensitive device.

Abstract: A touchscreen display assembly has an array of first electrodes distributed across an active area of the touchscreen display assembly such that the density of first electrodes increases in a first direction across the touchscreen. An array of second electrodes is distributed across an active area of the touchscreen display assembly such that the density of second electrodes decreases in the first direction across the touchscreen. The position in the first direction of an input on the touchscreen can be determined by the proportion of first and second electrodes density in the area of the input.

Abstract: A device includes a plurality of adjacent electrodes for a touch sensitive device. The electrodes run generally in a first direction. Adjacent electrodes are interdigitated to provide one or more interpolation sections of the electrodes. Touch sensitive devices may utilize such interdigitated electrodes as drive electrodes, along with transverse sense electrodes formed over a display.

Abstract: A capacitive sensor for determining the presence of an object, such as a user's finger or a stylus, is provided. The sensor comprises a substrate, for example made of transparent plastics material, such as PET, on which electrodes are deposited. A resistive drive electrode for example formed of transparent ITO, is arranged on one side of the substrate and a resistive sense electrode, which again may be of transparent ITO, is arranged on the other side of the substrate. Thus an overall transparent sensor may be provided. A shorting connection is also provided which is configured to connect between two locations on one of the electrodes. The electrodes are connected to respective drive and sense channels. By providing the shorting connection between two locations on one or other (or both) of the electrodes, a lower resistance connection is provided between other locations on the electrode and the corresponding drive or sense channel.

Abstract: Apparatus and methods are described for selecting which of a plurality of simultaneously activated keys in a keyboard based on capacitive sensors is a key intended for selection by a user. In embodiments of the invention keys are preferentially selected as the user intended key based on their positions within the keyboard. Thus a key which is frequently wrongly activated when a user selects another key, e.g. because the key is adjacent the intended key and the user normally passes his finger over it while approaching the desired key, can be suppressed relative to the desired key based on their relative positions. For example, keys may be associated with predefined rankings according to their position within the keyboard and in use keys are preferentially select according to their rankings. Alternatively, signals from the keys may be scaled by weighting factors associated with their positions and a key selected according to the weighted signals.

Abstract: Method and apparatus are provided for a capacitive sensor. In an example, a capacitive sensor can include a first sensing element, a sensing channel operable to generate a first signal indicative of first capacitance between the sensing element and a system ground, and a processor responsive to a change in the first capacitance between the first sensing element and ground. The processor can be configured to adjust a parameter value based on a first duration of the change in the first capacitance.

Abstract: A touch sensitive position sensor for detecting the position of an object in two dimensions is described. The position sensor has first and second resistive bus-bars spaced apart with an anisotropic conductive area between them. Electric currents induced in the anisotropic conductive area by touch or proximity flow preferentially towards the bus-bars to be sensed by detection circuitry. Because induced currents, for example those induced by drive circuitry, flow preferentially along one direction, pin-cushion distortions in position estimates are largely constrained to this single direction. Such one-dimensional distortions can be corrected for very simply by applying scalar correction factors, thereby avoiding the need for complicated vector correction.

Abstract: A sensor for determining a position for an adjacent object in two dimensions is described. The sensor comprises a substrate with a sensitive area defined by a pattern of electrodes, wherein the pattern of electrodes includes a first group of drive elements interconnected to form a plurality of row electrodes extending along a first direction, a second group of drive elements interconnected to form a plurality of column electrodes extending along a second direction, and a group of sense elements interconnected to form a sense electrode extending along both the first and second directions. The sensor further comprises a controller comprising a drive unit for applying drive signals to the row and column electrodes, and a sense unit for measuring sense signals representing a degree of coupling of the drive signals applied to the row and column electrodes to the sense electrode. Thus a 2D position sensor requiring only a single sense channel is provided.

Abstract: Keyboards, keypads and other data entry devices can suffer from a keying ambiguity problem. In a small keyboard, for example, a user's finger is likely to overlap from a desired key to onto adjacent ones. An iterative method of removing keying ambiguity from a keyboard comprising an array of capacitive keys involves measuring a signal strength associated with each key in the array, comparing the measured signal strengths to find a maximum, determining that the key having the maximum signal strength is the unique user-selected key, and maintaining that selection until either the initially selected key's signal strength drops below some threshold level or a second key's signal strength exceeds the first key's signal strength.

Abstract: A two-dimensional position sensor is formed by drive electrodes (52) and sense electrodes (62, 64, 66) both extending in the x-direction and interleaved in the y-direction. The sense electrodes comprise several groups, two of which co-extend in the x-direction over each different portions of extent in the x-direction. The drive and sense electrodes are additionally arranged to capacitively couple with each other. In use, drive signals are applied to the drive electrodes and then the resultant sense signals received from the sense electrodes measured. The position of a touch or stylus actuation on the sensor is determined in the x- and y-directions as follows. In the x-direction, the position is determined by an interpolation between sense signals obtained from co-extending pairs of sense electrodes, and in the y-direction by interpolation between sense signals obtained from different sequences of drive signals applied to the drive electrodes.

Abstract: A capacitive touch sensor employing adjacent drive and sense electrodes, in which an additional sense electrode is provided as well as a conventional drive electrode and sense electrode. The drive and two sense electrodes are arranged on the bottom side of a dielectric panel, the top side providing a sensing surface to be touched by a user's finger or a stylus. The additional sense electrode is positioned on the underside of the dielectric panel so that it is shielded from the drive electrode by the conventional sense electrode. The signal collected from the additional sense electrode is subtracted from the signal collected from the conventional sense electrode to cancel noise.