Patent application number | Description | Published |
20090115431 | Capacitive position sensor - A capacitive touch sensor is provided having sensing path for setting a color parameter to a desired value within a range, the color parameter being color hue, color saturation or color temperature. The sensor has a first mode of operation in which a parameter can be set approximately to a desired value and a second mode in which the value can be refined to the exact amount. In the first mode, the full range of possible values is mapped onto the sensing path and a user touch selects a value within the full range according to its position along the sensing path. In the second mode a finer adjustment is provided for, either by mapping a narrower sub-range of the full range onto the sensing path, or by allowing incremental adjustment of the parameter from the value initially set in the first mode, each incremental unit of adjustment being triggered by the object being displaced through a pre-determined threshold displacement along the sensing path. Switching from the first mode to the second mode is triggered if moving displacement of the object along the sensing path from the first point of touch exceeds a minimum threshold value. This provides an intuitive transition for the user from coarse to fine adjustment. | 05-07-2009 |
20090303198 | CAPACITIVE SENSING WITH HIGH-FREQUENCY NOISE REDUCTION - A method and apparatus for sensing the presence of a body from a change in an amount of charge present on a capacitively charged key includes performing a measurement burst which generates a plurality of signal sample values from a plurality of measurement cycles. Each of the measurement cycle includes inducing charge onto the key during a drive part of the measurement cycle, measuring during a signal measurement part of the measurement cycle the charge induced on the key during the drive part of the measurement cycle, and generating a signal sample value to represent of the charge measured from the key during the signal measurement part of the measurement cycle. The method includes comparing the value of the plurality of the signal sample values of the measurement burst with a determined range of accepted values between a determined maximum and a determined minimum value, and processing any of the plurality of signal sample values, which are outside the determined accepted range to the effect that the presence of the body can be determined only from a change in the value of one or more of the plurality of signal samples which are within the determined accepted range. By removing the effects of signal sample values, which are outside the determined accepted range of values, then the effects of noise, such as rectangular noise, which might otherwise cause a body to be erroneously detected can be substantially reduced. | 12-10-2009 |
20090303203 | CAPACITIVE SENSING WITH LOW-FREQUENCY NOISE REDUCTION - A method of sensing the presence of a body from a change in an amount of charge present on a capacitively charged key. The method comprises inducing charge onto the key during a drive part of a measurement cycle, coupling a signal measurement capacitor to the key during a signal measurement part of the measurement cycle to the effect that the charge induced on the key during the drive part of the measurement cycle is transferred to the signal measurement capacitor, determining from a noise measurement part of the measurement cycle an amount of charge induced on the key by noise during the signal measurement part of the measurement cycle, and controlling the drive part, the signal measurement part and the noise measurement parts of the cycle to provide the charge sensing circuit with a measurement of the signal from which the noise induced on the key has been or can be substantially cancelled. | 12-10-2009 |
20100044122 | Capacitive Touch Screen with Noise Suppression - A capacitive touch sensor wherein the touch sensitive panel has drive electrodes arranged on the lower side of a substrate and sense electrodes arranged on the upper side. The drive electrodes are shaped and dimensioned to substantially entirely cover the touch sensitive area with individual drive electrodes being separated from each other by small gaps, the gaps being so small as to be practically invisible. The near blanket coverage by the drive electrodes also serves to screen out interference from noise sources below the drive electrode layer, such as drive signals for an underlying display, thereby suppressing noise pick-up by the sense electrodes that are positioned above the drive electrodes. | 02-25-2010 |
20100045632 | Capacitive Position Sensor - A capacitive position sensor has a two-layer electrode structure. Drive electrodes extending in a first direction on a first plane on one side of a substrate. Sense electrodes extend in a second direction on a second plane on the other side of the substrate so that the sense electrodes cross the drive electrodes at a plurality of intersections which collectively form a position sensing array. The sense electrodes are provided with branches extending in the first direction part of the way towards each adjacent sense electrode so that end portions of the branches of adjacent sense electrodes co-extend with each other in the first direction separated by a distance sufficiently small that capacitive coupling to the drive electrode adjacent to the co-extending portion is reduced. Providing sense electrode branches allow a sensor to be made which has a greater extent in the first direction for a given number of sense channels, since the co-extending portions provide an interpolating effect. The number of sense electrode branches per drive electrode can be increased which allows a sensor to be made which has ever greater extent in the first direction without having to increase the number of sense channels. | 02-25-2010 |
20100097077 | SENSOR AND METHOD OF SENSING - A touch sensor senses the presence of an object at one of a plurality of channels on a surface of the touch sensor, wherein proximity of the object to the touch sensor results in a change in capacitance at the position of the channel. The touch sensor includes a drive circuit and a charge sensing circuit, each coupled to each of the channels. The charge sensing circuit includes at least one charge measurement capacitor. A measurement cycle is applied to the touch sensor having a drive portion and a sense portion. During the drive portion a charge is applied to the channels and therefore the charge measurement capacitors of the touch sensor, and during a sense portion the charge measurement capacitors are discharged by a predetermined amount and the remaining charge on the charge measurement capacitors is measured. | 04-22-2010 |
20100097078 | Noise Handling in Capacitive Touch Sensors - In a capacitive sensor of the type having X electrodes which are driven and Y electrodes that are used as sense channels connected to charge measurement capacitors, signal measurements are made conventionally by driving the X electrodes to transfer successive packets of charge to the charge measurement capacitors. However, an additional noise measurement is made by emulating or mimicking the signal measurement, but without driving the X electrodes. The packets of charge transferred to the charge accumulation capacitor are then indicative of noise induced on the XY sensing nodes. These noise measurements can be used to configure post-processing of the signal measurements. | 04-22-2010 |
20100097133 | Signal Processing - An iterative method for generating a series of output signal values from a series of input signal values is described. Iterations of the method comprise the steps of obtaining a current input signal value for the current iteration, comparing the current input signal value with an output signal value determined in a previous iteration, updating a counter value determined in the previous iteration based on the result of the comparison between the current input signal value and the previous output signal value such that the updated counter value replaces the counter value determined in the previous iteration, determining a slew value based on the counter value; and adding the slew value to the previously determined output signal value to generate a new current output signal value. Thus different slew values may be added to the previous output signal to obtain a new output signal. The counter value is updated so that its value reflects recent trends in the input signals. E.g. if the input signal is on an upward trend, the counter value may achieve a relative high value, for example because it is incremented each time an input signal exceeds a previously determined output signal. The magnitude of the slew values may increase as the counter value increases, thereby allowing the output signals to more rapidly track changes in the input signals. | 04-22-2010 |
20100123670 | Touch Screen Sensor - A two-dimensional touch sensor comprising a plurality of electrodes arranged in a mesh pattern on a substrate. Each electrode is formed by interconnected metal traces, the metal being intrinsically opaque, but the metal traces being sufficiently narrow to be practically invisible. The metal traces have a width less than or equal to 10 μm and occupy less than or equal to 5% of the area of each electrode. The electrodes can be deposited additively via a printing process, for example using copper as the metal. The narrow width of the tracks allows the film to be highly transparent, since the electric field used in capacitive touch screens can be made to propagate with very low metal densities. | 05-20-2010 |
20100164889 | MULTIPLE ELECTRODE TOUCH SENSITIVE DEVICE - Two different sets of electrodes in a touch sensitive device are formed to produce an electric field gradient from one end of the electrodes to the other end when opposite ends of the electrodes are driven with different voltages. A signal measuring cycle is performed by alternately driving the ends of one set of electrodes, while using the other set of electrodes to receive signals. The roles of the sets of electrodes are then reversed, such that the set that that was driven is now used to receive signals from the other set of electrodes. Reference signals may be obtained by driving both sides of one set of electrodes, and then both sides of the other set of electrodes. The signals obtained are then used to determine the touch position on the touch sensitive device. | 07-01-2010 |
20100214259 | SENSOR AND METHOD OF SENSING - A sensor is arranged to determine the presence of an object from a change in a capacitance of a sensing element. The sensor includes a capacitance measurement circuit operable to perform measurement cycles to measure a capacitance of the sensing element, and a controller circuit. The control circuit is operable to detect a periodic noise signal induced on the sensing element, to determine a first part, of a repeating pattern of the periodic noise signal, which causes a change in an amount of charge present on the sensing element, which affects the measurement of the capacitance of the sensing element by the capacitance measurement circuit, to determine a second part of the repeating pattern of the periodic noise signal, which does not cause a change in the amount of charge present on the sensing element, and to control the measurement cycles of the capacitance measurement circuit to perform the measurement cycles during the second part of the periodic noise signal and not to perform the measurement cycles during the first part of the periodic noise signal. | 08-26-2010 |
20100321043 | TWO-DIMENSIONAL POSITION SENSOR - A two-dimensional position sensor is formed by drive electrodes ( | 12-23-2010 |
20110043226 | CAPACITIVE SENSOR - 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. | 02-24-2011 |
20110043482 | ANISOTROPIC TOUCH SCREEN ELEMENT - 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. | 02-24-2011 |
20110095990 | INTERDIGITATED TOUCHSCREEN ELECTRODES - 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. | 04-28-2011 |
20110095991 | DRIVING ELECTRODES WITH DIFFERENT PHASE SIGNALS - 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. | 04-28-2011 |
20110095997 | TOUCHSCREEN ELECTRODE ARRANGEMENT - 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. | 04-28-2011 |
20110102331 | REDUNDANT TOUCHSCREEN ELECTRODES - 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. | 05-05-2011 |
20110102361 | TOUCHSCREEN ELECTRODE CONFIGURATION - 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. | 05-05-2011 |
20110157085 | Capacitive Keyboard with Position-Dependent Reduced Keying Ambiguity - 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. | 06-30-2011 |
20110254802 | NOISE REDUCTION IN CAPACITIVE TOUCH SENSORS - In touch sensitive display devices, the display scanning circuitry responsible for driving images of the panel screen can cause noise on the electrodes of nearby touch sensors. The display controller circuit and/or the touch sensor controller circuit of the exemplary touchscreen display devices may be configured to reduce such noise during the touch sensor acquisition cycle by implementing one or more of several techniques in which a portion of each of the sensor acquisition cycles occurs within a period of reduced noise from a cycle of the scanning of the display. | 10-20-2011 |
20110279398 | TOUCH SCREEN ELECTRODE ENHANCEMENTS - Darkening layers and/or passivation layers are provided on electrodes of panels for touch sensitive screens. Darkening, for example, reduces reflections of ambient light that might otherwise increase electrode visibility. Passivation reduces performance degradation due to electrode oxidation. A darkening layer may also serve as a passivation layer. | 11-17-2011 |
20120013544 | POSITION-SENSING PANEL AND METHOD - An exemplary touch position sensing panel includes an opaque electrode layer and a transparent electrode layer separated from the opaque electrode layer by a substrate. The electrodes are arranged such that nodes are formed in areas where the electrodes cross over each other. The transparent electrode layer shields the opaque layer from electric field noise from electric field sources underlying the position-sensing panel, such as a display, while at the same time providing transparency to light emitted from the underlying display. Techniques are also discussed for forming the transparent electrode layer and/or the opaque electrode layer. | 01-19-2012 |
20120013545 | ENHANCED CONDUCTORS - Disclosed examples of electrode structures and methods of manufacture thereof may provide one or more advantages relating to enhanced conductivity, for example, while providing optically clear conductors. | 01-19-2012 |
20140015796 | Capacitive Sensor with Reduced Noise - A capacitive touch sensor of the type employing adjacent drive and sense electrodes, in which an additional sense electrode Y1 is provided as well as the conventional drive electrode Xn and sense electrode Y0. 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. As a consequence, the conventional sense electrode is much more sensitive to the proximity of the finger or stylus than the additional sense electrode which primarily registers noise. The signal collected form the additional sense electrode is then subtracted from the signal collected from the conventional sense electrode, thereby to cancel noise. Another design provides similar functionality with a capacitive touch sensor of the type employing single-ended electrodes. | 01-16-2014 |