System and method for parallel touch sensing

Abstract

A system and method for sensing capacitance using an input device is provided. The input device includes a display, a touch sensor, and a processing system. The touch sensor has a plurality of transmitting electrodes, including a first subset of transmitting positive electrodes driven by a positive polarity sensing signal and a second subset of transmitting negative electrodes driven by a negative polarity sensing signal. Each transmitting positive electrode is spatially alternating with one of the transmitting negative electrodes from the second set of transmitting negative electrodes. The touch sensor includes a plurality of receiving electrodes arranged as differential pairs. Each differential pair includes a receiving positive electrode coupled to one or more of the transmitting positive electrodes from the first subset and a receiving negative electrode coupled to one or more of the transmitting negative electrodes from the second subset. The processing system transmits a positive polarity sensing signal and a negative polarity sensing signal, receives a first result signal from the receiving positive electrodes, and receives a second result signal from the receiving negative electrodes. The first and second result signals are combined to reduce noise.

Description

[Technical Field]

[0001] Cross-reference with related applications: This application claims the benefits of U.S. Patent Application No. 18 / 643,808, filed on 23 April 2024, entitled “System and Method for Parallel Touch Sensing,” and U.S. Provisional Application No. 63 / 465,201, filed on 9 May 2023, entitled “System and Method for Parallel Sensing in a Touch Sensor,” all of which are expressly incorporated by reference.

[0002] This disclosure, as a whole, relates to touch sensors. [Background technology]

[0003] Input devices such as touch sensors (commonly also called touchpads, touch sensors, or proximity sensors) are used in a variety of electronic systems. Typically, a touch sensor includes a sensing area, often demarcated by a defined area. Within this area, the touch sensor determines the presence, location, and / or movement of one or more input objects, usually allowing the user to provide user input for interacting with the electronic system. The input device may also be a touchscreen, comprising multiple electrodes, allowing the user to provide user input for interacting with the electronic system. In recent years, foldable devices with touchscreens or other types of capacitive sensors have been developed. Touch sensors may be integrated with displays, for example, as is commonly seen in mobile phones, laptops, and similar devices.

[0004] Touch sensor devices operating within electronic systems can distinguish between different types of touch events. For example, a finger touch may be interpreted as a selection of a specific location on a touchscreen, while a palm touch across a larger area of ​​the touchscreen may be interpreted differently and enable different functions. Detecting objects of varying dimensions can be unreliable with existing solutions, especially when noise reduction is applied. [Overview of the Initiative]

[0005] In an exemplary embodiment, a touch sensor is provided. The touch sensor includes a plurality of transmitting electrodes having a first subset of transmitting positive electrodes driven by a positive polarity sensing signal and a second subset of transmitting negative electrodes driven by a negative polarity sensing signal. Each transmitting positive electrode of the first subset of transmitting positive electrodes is spatially alternating with one transmitting negative electrode of the second subset of transmitting negative electrodes. The touch sensor also includes a plurality of receiving electrodes arranged as differential pairs. Each differential pair includes a receiving positive electrode coupled with at least one transmitting positive electrode of the first subset and a receiving negative electrode coupled with at least one transmitting negative electrode of the second subset. The touch sensor further includes a sensor circuit that supplies positive polarity sensing signals and negative polarity sensing signals, receives a first result signal from the receiving positive electrode, and receives a second result signal from the receiving negative electrode. The first and second result signals are combined to reduce noise.

[0006] In a further exemplary embodiment, an input device is provided. The input device includes a display, a touch sensor, and a processing system. The touch sensor has a plurality of transmitting electrodes having a first subset of transmitting positive electrodes driven by a positive polarity sensing signal and a second subset of transmitting negative electrodes driven by a negative polarity sensing signal. Each transmitting positive electrode of the first subset of transmitting positive electrodes is spatially alternating with a transmitting negative electrode of the second subset of transmitting negative electrodes. The touch sensor includes a plurality of receiving electrodes arranged as differential pairs. Each differential pair includes a receiving positive electrode coupled with at least one of the transmitting positive electrodes of the first subset and a receiving negative electrode coupled with at least one of the transmitting negative electrodes of the second subset. The processing system transmits a positive polarity sensing signal and a negative polarity sensing signal, receives a first result signal from the receiving positive electrodes, and receives a second result signal from the receiving negative electrodes. The first and second result signals are combined to reduce noise.

[0007] In yet another exemplary embodiment, a capacitance sensing method is provided. This method includes driving a plurality of transmitting positive electrodes with a positive polarity sensing signal and driving a plurality of transmitting negative electrodes with a negative polarity sensing signal, in a configuration in which a plurality of transmitting positive electrodes are spatially alternating with a plurality of transmitting negative electrodes. This method also includes receiving a first result signal from a plurality of receiving positive electrodes, in a configuration in which each receiving positive electrode is coupled with at least one of a plurality of transmitting electrodes, and receiving a second result signal from a plurality of receiving negative electrodes, in a configuration in which each receiving negative electrode is coupled with at least one of a plurality of transmitting negative electrodes. This method further includes combining the second result signal and the first result signal and determining the presence of an input object based on the combined result signal. [Brief explanation of the drawing]

[0008] [Figure 1] Figure 1 is a block diagram of an input device according to one or more embodiments.

[0009] [Figure 2] Figure 2 is a block diagram of an input device having an integrated display according to one or more embodiments.

[0010] [Figure 3] Figure 3 is a block diagram of a touch sensor having electrodes configured for parallel touch sensing, according to one or more embodiments.

[0011] [Figure 4] Figure 4 is a block diagram of a touch sensor having electrodes configured for parallel touch sensing, according to one or more embodiments.

[0012] [Figure 5A] Figure 5A shows the waveform of the resulting signal from the differential receiving electrode in a touch sensor device over a series of frames according to one or more embodiments.

[0013] [Figure 5B]FIG. 5B shows waveforms of result signals from differential receiving electrodes in a touch sensor device, spanning multiple differential receiving electrodes in the touch sensor device, according to one or more embodiments.

[0014] [Figure 6] FIG. 6 shows a method of performing capacitance sensing using parallel touch sensing, according to one or more embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The following detailed description is merely exemplary in nature and is not intended to limit the disclosure, application, or use of the methods and systems described herein. Further, there is no intention to be bound by any theory, whether explicitly or implicitly presented in the above technical field, background art, brief description of the drawings, or the following detailed description.

[0016] The exemplary systems and methods described herein provide the ability to detect input objects of various dimensions, including cases where the touch area is relatively large compared to the overall touch sensor. In conventional approaches, reducing noise can be difficult when detecting relatively large objects. Such problems can occur, for example, because some noise reduction techniques feedback the average result signal from a number or all of the sensing circuits (e.g., electrodes) to the touch sensor for the purpose of reducing noise. As a result, large-area touches output a result signal approximated to the average signal, which causes the touch signal to be canceled out or become very small, making measurement and detection difficult. According to the exemplary embodiments, the parallel sensing method and system are used to accurately and reliably detect input objects of various dimensions, including large input objects, and at the same time facilitate the reduction of noise generated by various sources.

[0017] FIG. 1 shows an input device 100 that supplies an input to an electronic system 102. This input device 100 can be used to implement capacitive parallel sensing in at least some of the modes described herein. Electronic systems in some non-limiting examples include desktop computers, laptop computers, netbook computers, tablets, terminals, kiosks, mobile phones (e.g., cellular phones), in-vehicle multimedia centers, Internet of Things (IoT) devices, and others. The input device 100 may be part of the electronic system 102 or a separate component communicatively connected to the electronic system 102.

[0018] The input device 100 includes a processing system 110 and sensor electrodes 105. The processing system 110 operates the sensor electrodes 105 to detect one or more input objects 140 or other conditions within the sensing region of the input device 100. Examples of the input object 140 include a finger and a stylus as shown in FIG. 1. The input object may include parts of the hand other than the finger, such as the palm and the side of the hand.

[0019] The sensing region of the input device 100 encompasses any space above, around, within, and / or in the vicinity of the input device 100. In this space, the input device 100 can detect user inputs, such as those provided by one or more input objects 140. In certain embodiments, the input device 100 can detect other conditions, such as the angle at which a foldable device is open.

[0020] The sensor electrode 105 is coupled to the processing system 110 via a conductive path such as a trace 150. The exemplary pattern of the sensor electrode 105 shown in Figure 1 comprises an array of sensor electrodes 105 arranged in multiple rows and columns. In one example, the sensor electrodes 105 are arranged in rows such as rows 170-181. In other embodiments, the sensor electrodes may be arranged in columns. The sensor electrodes 105 may be arranged in other patterns such as polarity arrays, repeating patterns, non-repeating patterns, non-uniform arrays, or other suitable arrangements. The sensor electrodes 105 may have any suitable shape, such as circular, rectangular, rhombus, star, square, non-convex, convex, non-concave, concave, or other geometric shapes.

[0021] The sensor electrode 105 may be arranged on a common layer. For example, the sensor electrode 105 may be arranged on the first surface of the common substrate. In other embodiments, the sensor electrode 105 may be arranged on two or more layers. For example, part of the sensor electrode 105 may be arranged on the first layer, and another part of the sensor electrode may be arranged on the second layer. The first and second layers may be arranged on different surfaces of the common substrate, or on different substrates.

[0022] The sensor electrode 105 may be composed of a conductive material such as a metal mesh or indium tin oxide (ITO). Furthermore, the sensor electrodes 105 may be ohmic insulated from each other so that one or more insulators separate the sensor electrodes and prevent electrical short circuits between them.

[0023] The processing system 110 includes a sensor circuit 104. Furthermore, the processing system 110 may also include a determination circuit 106. The processing system 110 operates the sensor electrode 105 to detect one or more input objects 140 or other conditions within the sensing area of ​​the input device 100. The processing system 110 is partially or entirely housed within one or more integrated circuits (ICs). For example, the processing system 110 may include a single IC chip, or it may include multiple IC chips. The processing system may also include one or more individual circuits.

[0024] The sensor circuit 104 is coupled to the sensor electrode 105 via the wiring trace 150 and drives the sensor electrode 105 with a sensing signal to detect one or more input objects 140 in the sensing area of ​​the input device 100. The sensor circuit 104 may also drive the sensor electrode 105 with other signals, such as a guard signal and / or a ground signal.

[0025] The sensor circuit 104 includes digital and / or analog circuits. For example, the sensor circuit 104 includes a transmitting circuit (or driving circuit) that drives or transmits a sensing signal to the sensor electrode 105, and a receiving circuit that receives a result signal from the sensor electrode 105. The transmitting circuit may include one or more amplifiers and / or one or more modulators that drive the sensing signal to the sensor electrode 105.

[0026] The processing system 110 may include an analog-to-digital converter (ADC and / or DAC) 154 and an analog front end (AFE) equipped with, for example, an integrator that receives the result signal from the sensor electrode 105. The processing system 110 may also include a compensation circuit 156 that supplies a signal to compensate for background capacitance. The ADC (and / or DAC) 154, AFE 152 and compensation circuit 156 may be part of the sensor circuit 104 or may form a separate circuit.

[0027] The sensor circuit 104 may drive the sensor electrodes in various modes. In some modes, the sensor circuit 104 may use all of the sensor electrodes 105 to detect an input object. In other modes, the sensor circuit 104 may use only a subset of the sensor electrodes 105 to detect an input object.

[0028] In certain embodiments or modes, the sensor circuit 104 drives one or more first sensor electrodes 105 with a transcapacitive sensing signal and receives the resulting signal with one or more second sensor electrodes 105 to operate the sensor electrodes 105 for transcapacitive sensing. Operating the sensor electrodes 105 for transcapacitive sensing detects a change in the capacitive coupling between the sensor electrode driven by the transcapacitive sensing signal and the sensor electrode acting as the receiving electrode. This capacitive coupling can be reduced when an input object (e.g., input object 140) coupled to the system ground approaches the sensor electrodes. Driving the sensor electrodes 105 with a transcapacitive sensing signal includes modulating the sensor electrodes 105 with reference to a reference voltage, such as the system ground. Transcapacitive sensing can be used in combination with parallel touch sensing modes, as shown in Figures 3 to 6. However, it will be understood that transcapacitive sensing is not limited to parallel touch sensing modes. For example, transcapacitive sensing may include driving a row of sensor electrodes 105 with a transcapacitive sensing signal, reading a column of sensor electrodes 105 to obtain a result signal, and / or the reverse process.

[0029] A transcapacitive sensing signal is a periodic or aperiodic signal that varies between two or more voltages. Furthermore, the transcapacitive sensing signal typically has a frequency between 50 Hz and 1 MHz, although other frequencies may be used in other embodiments. The amplitude range of the transcapacitive sensing signal, from minimum to maximum, may be in the range of about 1 V to about 10 V. However, in other embodiments, the amplitude range of the transcapacitive sensing signal may be greater than about 10 V or less than about 1 V. In addition, the transcapacitive sensing signal may have a square wave, sine wave, triangle wave, trapezoidal wave, sawtooth wave, or other waveform.

[0030] In some embodiments, operating the sensor electrode 105 to receive the resulting signal includes maintaining the sensor electrode 105 at a substantially constant voltage or modulating the sensor electrode 105 with respect to a transcapacitive sensing signal. The resulting signal includes effects corresponding to one or more transcapacitive sensing signals and / or one or more environmental interference sources (e.g., other electromagnetic signals).

[0031] In other embodiments or modes, the sensor circuit 104 operates the sensor electrode 105 for absolute capacitance sensing by driving one or more first sensor electrodes 105 with an absolute capacitance sensing signal and receiving a result signal with the driven sensor electrode. Operating the sensor electrode 105 for absolute capacitance sensing detects a change in the capacitive coupling between the sensor electrode driven by the absolute capacitance sensing signal and an input object (e.g., input object 140). The capacitive coupling of the sensor electrode 105 driven by the absolute capacitance sensing signal changes when an input object (e.g., input object 140) coupled to the system ground approaches the sensor electrode.

[0032] The absolute capacitance sensing signal is a periodic or aperiodic signal that varies between two or more voltages. Furthermore, the absolute capacitance sensing signal typically has a frequency between approximately 50 kHz and approximately 1 MHz. However, other frequencies may be used in other embodiments. In addition, the absolute capacitance sensing signal may have a square wave, sine wave, triangular wave, trapezoidal wave, sawtooth wave, or other waveform. The amplitude range of the absolute capacitance sensing signal from minimum to maximum may be in the range of approximately 1 V to approximately 10 V. However, in other embodiments, the amplitude range of the absolute capacitance sensing signal may be greater than approximately 10 V or less than approximately 1 V. In various embodiments, driving the sensor electrode 105 with the absolute capacitance sensing signal includes modulating the sensor electrode 105. The resulting signal received during the performance of absolute capacitance sensing may include the effects corresponding to one or more absolute capacitance sensing signals and / or one or more environmental interference sources (e.g., other electromagnetic signals). The absolute capacitance sensing signal may be the same as or different from the transcapacitive sensing signal used in transcapacitive sensing.

[0033] In certain embodiments, the sensor circuit 104 drives a subset of sensor electrodes 105 with a guard signal. Sensor electrodes driven with a guard signal may be referred to as guarded sensor electrodes or guard electrodes. Driving sensor electrodes with a guard signal reduces the voltage difference between the guarded sensor electrodes and sensor electrodes driven in parallel with an absolute capacitance sensing signal. As a result of driving a guard signal on one or more first sensor electrodes and simultaneously driving sensing signals on one or more second sensor electrodes, the capacitance between the guarded sensor electrodes and the sensor electrodes driven with the absolute capacitance sensing signal changes little to no.

[0034] It will be understood that the sensor circuit 104 can drive the sensor electrode 105 in multiple modes. For example, the sensor circuit 104 can drive the sensor electrode 105 in transcapacitive mode during a first period and in absolute capacitive mode during a second period. Furthermore, the sensor circuit 104 can drive the sensor electrode 105 in multiple versions of a particular mode. For example, the sensor circuit 104 can drive the sensor electrode in parallel transcapacitive sensing mode during a first period and in non-parallel transcapacitive sensing mode during a second period. Non-parallel transcapacitive sensing includes, for example, driving one row or column with a transcapacitive sensing signal and reading the resulting signal from the other row or column, as described above. Parallel transcapacitive sensing includes performing both driving and reading with electrodes facing approximately the same direction (e.g., non-overlapping).

[0035] The determination circuit 106 receives a result signal from the sensor circuit 104, processes the result signal, and determines a change in the capacitive coupling of the sensor electrode 105. The determination circuit 106 uses the change in the capacitive coupling of the sensor electrode 105 to determine the position information of one or more input objects (e.g., input object 140), or a change in capacitance due to other reasons. The determination circuit 106 may also perform other functions, such as measuring the amount of noise present in one or more areas of the sensing region, and / or determining whether the position information is corrupted or degraded by noise. In certain embodiments, the determination circuit 106 may synthesize the result signals. For example, the determination circuit 106 may subtract the result signal from one receiving electrode from the result signal from another receiving electrode to form a differential signal.

[0036] In one or more embodiments, a measured value of the change in capacitive coupling determined from the result signal received from the sensor electrode 105 may be used by the determination circuit 106 to form a capacitive image. The result signal used to detect the change in capacitive coupling is received in a capacitive frame. A capacitive frame may correspond to one or more capacitive images. Multiple capacitive images can be acquired over multiple periods, and the differences between these images can be used to derive information about the input object 140 within the sensing area of ​​the input device 100. For example, consecutive capacitive images acquired over consecutive periods can be used to track the movement of one or more input objects entering the sensing area, moving out of the sensing area, and moving within the sensing area.

[0037] As used herein, “location information” broadly encompasses absolute position, relative position, velocity, acceleration, and other appropriate types of spatial information in zero, one, two, or three dimensions. Exemplary “zero-dimensional” location information includes near / far distance or contact / non-contact information. Exemplary “one-dimensional” location information includes position along an axis. Exemplary “two-dimensional” location information includes motion on a plane. Exemplary “three-dimensional” location information includes instantaneous or average velocity in space. Further examples include other representations of spatial information. Historical data relating to one or more types of location information, such as historical data tracking position, motion, or instantaneous velocity over time, may also be determined and / or stored.

[0038] Figure 2 shows an example of an input device 100, which is shown superimposed on and / or integrated with the display of the display device 200. The display of the display device 200 may be any suitable type of display, such as light-emitting diodes (LEDs), micro-LEDs, organic LEDs (OLEDs), micro-OLEDs, liquid crystal displays (LCDs), plasma displays, electroluminescent displays (ELs), or other display technologies.

[0039] The display device 200 includes a display panel 210 which is communicatively coupled to a display driver 208 and a gate selection circuit 230. The display panel 210 includes display electrodes which are driven to update the subpixel electrodes 226 of the display panel 210. The display electrodes include data lines 222, gate lines 224, and others. The display driver 208 may be part of the processing system 110 (Figure 1) or may be a separate component.

[0040] Data line 222 is coupled to display driver 208, and gate line 224 is coupled to gate selection circuit 230. Each subpixel electrode 226 is coupled to one of the gate lines 224 and one of the data lines 222. The gate selection circuit 230 drives gate selection and gate deselection signals to the gate line 224 to select (activate) and deselect (deactivate) the corresponding subpixel to update it.

[0041] The display driver 208 includes a display driver circuit that drives a data line 222 with a subpixel data signal to update a selected subpixel electrode 226 and update the display of the display device 200. For example, the display driver 208 may drive a display update signal on the data line 222 during the corresponding display update period.

[0042] The display driver 208 updates the subpixel electrodes 226 during a display frame to update the image displayed on the display panel 210. The display frame is updated or refreshed approximately every 16 ms, generating a display refresh rate of approximately 60 Hz. In other embodiments, other display refresh rates may be used. For example, the display refresh rate may be 90 Hz, 120 Hz, 140 Hz, or higher.

[0043] The display driver 208, sensor circuit 104, determination circuit 106, AFE 152, ADC (and / or DAC) 154, and compensation circuit 156 may be part of a common processing system (e.g., processing system 110 forms a touch controller and a display controller). Alternatively, the display driver 208 may be part of a first processing system, and the sensor circuit 104, AFE 152, ADC (and / or DAC) 154, compensation circuit 156, and determination circuit 106 may be part of a second processing system. Furthermore, the display driver 208, sensor circuit 104, AFE 152, ADC 154, compensation circuit 156, and determination circuit 106 may be part of a common IC chip. Alternatively, one or more of these components may be placed on a first IC chip, and one or more other of these components may be placed on a second IC chip, and so on. Alternatively, the sensor circuit 104, AFE 152, ADC (and / or DAC) 154, compensation circuit 156, and / or determination circuit 106 may be implemented entirely or partially by one or more individual circuits.

[0044] In various embodiments, the sensor circuit 104 performs capacitance sensing by driving the sensor electrodes at the capacitance frame rate during the capacitance frame. Furthermore, each capacitance frame may include multiple periods during which different sensor electrodes 105 perform capacitance sensing.

[0045] The "capacitance frame rate" (the rate at which consecutive capacitance images are acquired) may be the same as or different from the "display frame rate" (the rate at which display images are updated, and updating display images includes refreshing the screen to redisplay the same image). In various embodiments, the capacitance frame rate is an integer multiple of the display frame rate. In other embodiments, the capacitance frame rate is a fractional multiple of the display frame rate. In yet another embodiment, the capacitance frame rate may be any fractional or integer multiple of the display frame rate. Furthermore, the capacitance frame rate may be a rational number (e.g., 1 / 2, 2 / 3, 1, 3 / 2, 2) times the display frame rate. In one or more embodiments, the capacitance frame rate may remain constant while the display frame rate changes. In other embodiments, the capacitance frame rate may increase or decrease while the display frame rate remains constant. Alternatively, to minimize interference "beat frequency" between display updates and input sensing, the capacitance frame rate may be asynchronous with the display refresh rate, or the ratio of the capacitance frame rate to the display rate may be an unrational number.

[0046] In one or more embodiments, capacitance sensing (or input sensing) and display updating may occur during periods of at least partial overlap. For example, the sensor circuit 104 operates the sensor electrode 105 for capacitance sensing while the display driver 208 operates the gate line 224 and data line 222 to update the image displayed on the display panel 210. For example, updating the display panel 210 and operating the sensor electrode 105 for capacitance sensing may be asynchronous. Furthermore, updating the display panel 210 and operating the sensor electrode 105 for capacitance sensing may or may not be synchronous.

[0047] In one or more embodiments, the updating of the display panel 210 and the operation of the sensor electrode 105 to perform capacitance sensing may occur in non-overlapping periods. For example, the updating of the display panel 210 may occur during the display update period, while the operation of the sensor electrode 105 to perform capacitance sensing may occur during the non-display update period. The non-display update period may be a blanking period that occurs between the last line of one display frame and the first line of the next display frame (e.g., during a vertical blanking period). Furthermore, the non-display update period may occur between the display line update periods of two consecutive display lines in a display frame and have at least the same duration as the display line update periods. In such embodiments, the non-display update period may be called a long horizontal blanking period or a long h-blanking period, and the blanking period occurs between two display line update periods in a display frame and has at least the same duration as the display line update periods.

[0048] Figure 3 shows an example of a touch sensor having sensor electrodes 105 for parallel sensing according to a particular embodiment. In the example in Figure 3, the sensor electrodes 105 can operate in transcapacitive sensing mode. The sensor electrodes 105 used for parallel sensing may include all or only a subset of the sensor electrodes of the input device 100. For example, in the case of a touch sensor with 16 × 40 electrodes, the parallel sensing mode may include only 6 transmitting electrodes and 10 receiving electrodes, compared to 16 transmitting electrodes and 40 receiving electrodes in non-parallel transcapacitive sensing. Of course, this is merely an example, and all of the sensor electrodes 105 or any suitable subset thereof may be used.

[0049] The illustrated sensor electrodes 301-319 are arranged approximately parallel to each other, for example, without overlapping. Although electrodes 301-319 are illustrated in a vertical direction, they may face any desired direction, such as horizontally or diagonally. While each of electrodes 301-319 is shown as a single sensor element, it will be understood that each of sensor electrodes 301-319 may contain one or more individual electrodes, as shown and described in relation to rows or columns 170-181 in Figure 1, for example.

[0050] In the embodiment shown in Figure 3, seven transmitting electrodes 301-307 and twelve receiving electrodes 308-319 are shown. The number of transmitting and receiving electrodes is not limited to the number shown and can vary greatly depending on, for example, the overall dimensions of the touch sensor, the desired resolution, the pitch of the sensor electrodes, and the desired dimensions of the sensor used for parallel touch sensing.

[0051] A first subset of transmitting electrodes 301, 303, 305, and 307 represents positive polarity transmitting electrodes, referred to as transmitting positive electrodes, and a second subset of transmitting electrodes 302, 304, and 306 represents negative polarity transmitting electrodes, referred to as transmitting negative electrodes. The transmitting positive and transmitting negative electrodes are arranged alternately, for example, transmitting negative electrode 302 spatially follows transmitting positive electrode 301, transmitting negative electrode 303 spatially follows transmitting negative electrode 302, and so on. As will be described in detail later, the transmitting positive electrodes are driven by a positive polarity sensing signal, and the transmitting negative electrodes are driven by a relatively negative sensing signal, or a sensing signal with the opposite polarity. For example, the negative polarity sensing signal may be the inverse of the positive polarity transmitting signal, and the negative polarity sensing signal is 180 degrees out of phase with respect to the positive polarity sensing signal. In some embodiments, the transmitting electrodes may be driven by a positive polarity sensing signal at one point in time and by a negative polarity sensing signal at another point in time. Therefore, the terms “transmit positive” and / or “transmit negative” may refer to a specific point in time. Touch-to-display (T2D) noise can be reduced by alternating the polarity or phase of the transmitted sensing signal.

[0052] The receiving electrodes 308-319 are arranged as a differential pair. Receiving electrodes 308, 311, 312, 315, 316, and 319 are receiving positive electrodes arranged to capacitively couple with at least one transmitting positive electrode. For example, receiving positive electrode 308 is capacitively coupled adjacent to transmitting positive electrode 301. As a second example, receiving positive electrode 319 is capacitively coupled adjacent to transmitting positive electrode 307.

[0053] The receiving electrodes 309, 310, 313, 314, 317, and 318 are receiving negative electrodes arranged to capacitively couple with the transmitting negative electrode. For example, receiving negative electrode 309 is capacitively coupled adjacent to transmitting negative electrode 302. As a second example, receiving negative electrode 318 is capacitively coupled adjacent to transmitting negative electrode 306. The receiving positive and receiving negative electrodes generate a resulting signal with signal strength depending on whether or not an input object is present nearby. The resulting signal may also include noise generated by the display or other sources, one example being zebra noise generated by a displayed zebra pattern, which is, for example, a pattern of alternating dark rows or columns and bright rows or columns.

[0054] Capacitive coupling exists between the transmitting electrode and the adjacent receiving electrode. For example, as shown in the figure, capacitance C0 + This represents capacitive coupling between the transmitting positive electrode 301 and the receiving positive electrode 308. Capacitance C0 - This represents capacitive coupling between the transmitting negative electrode 302 and the receiving negative electrode 309. The amount of capacitive coupling changes depending on the presence or absence of an input object, and also changes due to the other factors mentioned above.

[0055] As shown in the example in Figure 3, the arrangement of transmitting and receiving electrodes yields a differential pair of receiving positive and receiving negative electrodes positioned between the transmitting positive and transmitting negative electrodes. For example, the first receiving electrode pair 308, 309 is positioned between the transmitting positive electrode 301 and the transmitting negative electrode 302. Similarly, the second receiving electrode pair 310, 311 is positioned between the transmitting negative electrode 302 and the transmitting positive electrode 303, and so on. Each electrode pair, for example, a pair of adjacent receiving electrodes, forms a differential pair. Noise can be reduced by combining the resulting signals. For example, noise can be reduced by subtracting the resulting signal read from one receiving electrode of the differential pair from the resulting signal read from the other receiving electrode of the differential pair, for example, by subtracting the resulting signal read from the receiving negative electrode 309 from the resulting signal read from the receiving positive electrode 308. Since noise tends to affect each receiving electrode of the differential pair equally, the noise can be minimized or eliminated. Subtracting one result signal from another in this way cancels out or reduces noise such as display noise.

[0056] Figure 3 shows an example with a total of 19 electrodes. Such exemplary arrangements may include transmitting positive electrodes at both ends of the sensor electrode 105. Many other arrangements are possible. For example, in an 18-electrode arrangement, one of the end transmitting electrodes may be removed. In another example, in a 17-electrode arrangement, both end transmitting electrodes may be removed. In yet another example, in a 16-electrode arrangement, three consecutive electrodes may be removed, for example, the three electrodes on the far right as shown in Figure 3, or the three electrodes on the far left. These configurations are, of course, shown as examples and are not limiting.

[0057] Generally, receiving positive and receiving negative electrodes are always provided in pairs, but depending on the total number of electrodes, the end transmitting electrodes may not be present. However, with respect to the transmitting positive and transmitting negative electrodes, the difference in the total number of rows of all driving transmitting electrodes is usually either 0 (the number of transmitting positive and transmitting negative electrodes is the same) or 1 (the number of positive and negative electrodes is different). These configurations minimize touch-to-display (T2D) noise because the noise from the transmitting positive electrode usually cancels out or minimizes the noise from the transmitting negative electrode.

[0058] In some embodiments, the transmitting and receiving electrodes may be shifted over time, and this process may include, for example, converting one or more transmitting electrodes into receiving electrodes and converting one or more receiving electrodes into receiving electrodes or transmitting electrodes with opposite polarities. For example, FIG. 3 may show the configuration of the transmitting and receiving electrodes in a first period (e.g., the first capacitance frame). In a subsequent second period (e.g., the second capacitance frame), electrode 308 becomes the transmitting positive electrode, electrode 309 becomes the receiving positive electrode, electrode 302 becomes the receiving negative electrode, electrode 310 becomes the transmitting negative electrode, and so on, and the configuration may shift. This sequence reflects a shift from left to right, but a shift from right to left is also conceivable. Shifting the electrodes as described above can facilitate minimizing dead spots within the detection pattern, such as when the input object is directly above the transmitting electrode or when the input object is centered between the receiving electrodes.

[0059] During operation, the touch controller or other processing system 110 drives the transmitting positive electrode with a positive-polarity sensing signal and drives the transmitting negative electrode with, for example, a sensing signal of opposite polarity (e.g., a negative-polarity sensing signal or an inverted positive-polarity sensing signal) to generate a differential signal. The processing system 110 may read the resultant signal on the receiving electrodes and process it as a differential resultant signal. For example, the resultant signal at the receiving positive electrode 308 (C0 + ) and the resultant signal at the receiving negative electrode 309 (C0 - ) are read and processed as a differential pair. Similarly, the processing system 110 processes the receiving pairs 310 (C1 - ), 311 (C1 + ), the receiving pairs 312 (C2 + ), 313 (C2 - ), the receiving pairs 314 (C3 - ), 315 (C3 + ), the receiving pairs 316 (C4 + ), 317 (C4 - ), the receiving pairs 318 (C5 - ), 319 (C5 +The resulting signals from each pair are read and processed. The resulting signals from each pair are combined, for example, into a differential signal (C i + -C i - It is processed as C. i This corresponds to capacitive coupling between the transmitting electrode and the adjacent receiving electrode. In this way, noise can be reduced as described above by subtracting one result signal from the other result signal. Before the result signals are processed in this manner, other noise reduction techniques such as analog display noise suppression (ADNS) may be applied to the result signals to avoid saturation of system components such as AFE.

[0060] The embodiments described herein provide accurate detection for both small and large objects without sacrificing noise reduction. For example, a small object, including but not limited to a finger or stylus, may touch the touch sensor device at position 320. The position of the touch position 320 is closer to the receiving electrode 312 than to the receiving electrode 313. As a result of the difference in capacitive coupling, the touch generates a different result signal at the receiving electrode 312 than the result signal at the receiving electrode 313. These different result signals are analyzed by the processing system 110. For example, when the differential signal exceeds a threshold, the differential signal is interpreted by the processing system 110 as a touch at the position of the receiving electrode 312. The differential signals of other differential pairs, such as differential pairs 314, 315, are close to zero or at least below the threshold, and therefore indicate that there is no contact of an object with the touch sensor device along the receiving electrodes 314, 315.

[0061] As another example, a large object, including but not limited to the palm or side of the hand, may come into contact with the touch sensor device at position 322. The position 322 of the second contact covers a wider area than touch 320, and generally covers and capacitively couples with multiple differential receiving pairs, such as electrodes 316, 317, 318, 319. The differential signals measured by the processing system 110 at each differential pair are relatively large, for example, exceeding a threshold, thus indicating that an object has come into contact with the touch sensor device in the area of ​​receiving electrodes 316, 317 and receiving electrodes 318, 319. Similar to the example of the small object 320, the differential signals at other differential pairs, such as differential pairs 308, 309, are close to zero or below a threshold, thus indicating that an object has not come into contact with the touch sensor device at the positions of the other receiving electrodes.

[0062] In both the case of small objects such as touch 320 and large objects such as touch 322, the differential signal pairs are read and combined, processed as a difference signal, for example, by subtracting one signal from the other, thus canceling out noise. Unlike conventional touch sensors, this arrangement thus reduces noise and accurately detects touches from objects of various sizes, including relatively large objects.

[0063] It will be understood that touch sensors do not necessarily have to operate in parallel transcapacitive mode. For example, touch sensors may operate in conventional transcapacitive mode at various points in time. In this mode, a sensor in one direction, such as row direction, is driven by a sensing signal, and the resulting signal is read from an electrode in another direction, such as column direction, and vice versa. The electrodes may then operate in another mode for parallel transcapacitive sensing. At various points in time, the electrodes may operate in yet another mode for absolute capacitance sensing.

[0064] Figure 4 shows another example of a touch sensor 400 having sensor electrodes 105 for parallel sensing according to a particular embodiment. Similar to the example in Figure 3, the sensor electrodes shown in Figure 4 may operate in parallel transcapacitive sensing mode for at least a certain period of time. The operation of the touch sensor shown in Figure 4 is substantially the same as that of the example in Figure 3 and will not be repeated here. Similar to the example in Figure 3, the touch sensor 400 may consist of only a subset of all electrodes available for capacitive sensing.

[0065] The sensor electrodes 401-416 are shown arranged approximately parallel to each other and drawn perpendicularly, but they may face any desired direction. The embodiment shown in Figure 4 shows six transmitting electrodes 401-406 and ten receiving electrodes 407-416, but as with Figure 3, this embodiment is not limited to a specific number of electrodes and any suitable number may be used. The transmitting electrodes are arranged so that their polarity alternates, for example, a transmitting positive electrode 401 is followed by a transmitting negative electrode 402, then a transmitting positive electrode 403, and so on. The transmitting positive electrode may be driven by a positive polarity sensing signal that is the opposite of the negative polarity sensing signal used to drive the transmitting negative electrode, for example, with a phase shift of 180 degrees. The alternating arrangement of the transmitting positive and transmitting negative electrodes reduces T2D noise as described above.

[0066] The receiving electrodes 407-416 are arranged as a differential pair between the transmitting positive and transmitting negative electrodes. For example, the receiving positive electrode 407 is adjacent to the transmitting positive electrode 401 and is capacitively coupled. As a second example, the receiving negative electrode 416 is adjacent to the transmitting negative electrode 406 and is capacitively coupled. The arrangement of the differential pair of receiving electrodes reduces display noise as described above.

[0067] However, unlike the example in Figure 3, the touch sensor 400 shown in Figure 4 includes mismatched electrodes, such as sensor electrodes of different lengths for transmitting and / or receiving. For example, transmitting electrodes 404-406 and receiving electrodes 413-416 are longer than transmitting electrodes 401-403 and receiving electrodes 407-412. Furthermore, in the illustrated example, at least one differential pair of receiving electrodes 411, 412 is mismatched in that the receiving negative electrode 412 is longer than the receiving positive electrode 411. In this particular example, the longer electrodes are positioned closer to the processing system 110 compared to the shorter electrodes, but the embodiment here assumes electrodes of various lengths without limitation in terms of the relative positions of the electrodes.

[0068] Embodiments in which the transmitting and receiving electrodes have different lengths are effective for noise reduction and accurate detection of touches of varying sizes, regardless of the size mismatch. It will be understood that any size mismatch of the transmitting electrodes, for example, transmitting electrodes 401-406, is not fatal from the standpoint of noise reduction. Mismatches between receiving electrodes may be more pronounced, but this configuration minimizes the impact on display noise reduction. For example, in this example, there is a slight dimensional mismatch between the receiving electrodes of the differential pair 411, 412. However, the impact on noise reduction can be minimized by keeping the amount of mismatch to a minimum, for example, less than 80%, less than 90%, or less than 6%, and / or by positioning the mismatch close to the processing system 110 with respect to the far end of the sensor.

[0069] Figure 5A shows the waveform 500 of the differential receiving electrode signal over a series of capacitive sensing frames in the region near the touch in a touch sensor device under noisy conditions. The y-axis (vertical axis) represents the signal intensity of the differential signal measured by one or more differential receiving electrode pairs within the touch region. For example, the y-axis can represent the signal level of the differential signal measured between the receiving electrodes, as illustrated and described in relation to Figure 3. The x-axis (horizontal axis) represents the frame number, for example, a series of measurements over time. As can be seen from Figure 5A, the resulting signal can be read over a series of frames, each frame representing readings obtained from some or all of the receiving electrodes from a burst of sensing signal.

[0070] At time 510, a large object may have been placed on the touch sensor device. This object may include, but is not limited to, a palm, side, etc., as shown in touch 322 in Figure 3. The resulting signal level may have increased at the receiving electrode adjacent to the touch area. This reflects a large differential signal received by the receiving electrode pair. At time 520, an interference signal may have been introduced, such as display interference due to the display of a zebra pattern, but it will be understood that this embodiment is effective in mitigating various types of noise. As can be seen from the figure, the intensity of the resulting signal due to the touch is much greater than the noise, as a result of noise reduction provided, for example, by differential measurement.

[0071] At time 530, the large object may have been removed from contact with the touch sensor device. Figure 5A also shows signals from touches by smaller objects, such as touch 320 shown in Figure 3. As a specific example, at time 540, a finger may have been placed on the touch sensor device. As shown in Figure 5A, the signal level increases and may be detected as a finger touch on the touch sensor device. Thus, as explained with reference to Figure 3, the differential pair of the receiving electrode and the differential pair of the transmitting electrode can detect both large and small objects while reducing noise.

[0072] Figure 5B shows the waveform 550 of the differential receiving electrode signal across a touch sensor device for small objects such as finger touches. The y-axis (vertical axis) represents the signal intensity level of the differential signal measured between each receiving electrode pair. The x-axis (horizontal axis) identifies a specific receiving electrode (Rx) pair by number. For example, referring to Figure 3, receiving electrodes 308 and 309 form pair 0, receiving electrodes 310 and 311 form pair 1, and so on. The illustrated example shows the signal intensity across 12 receiving electrode pairs, each pair having a receiving positive electrode and a receiving negative electrode. Of course, any appropriate number of receiving electrode pairs may be used as described above.

[0073] As shown in the figure, at position 560, the processing system 110 may read relatively low-level result difference signals for receiving electrode pair 1 (e.g., corresponding to receiving electrodes 310 and 311) and receiving electrode pair 2 (e.g., corresponding to receiving electrodes 312 and 313), indicating that no object is in contact with the touch sensor device in the vicinity of receiving electrode pairs 1 and 2. For example, the signal strength indicated by receiving electrode pairs 1 and 2 may not exceed the threshold 590.

[0074] At position 570, the processing system 110 may read relatively high-level result differential signals, for example, sensing signals exceeding threshold 590, for receiving electrode pair 3 (e.g., corresponding to receiving electrodes 314 and 315) and receiving electrode pair 4 (e.g., corresponding to receiving electrodes 316 and 317). High-level differential signals indicate that an object is in contact with or near the touch sensor device in the vicinity of receiving electrode pairs 3 and 4.

[0075] At position 580, the processing system 110 may again read low-level result differential signals for receiving electrode pairs 5-12, for example, differential signals below threshold 590. Low-level differential signals indicate that no object is in contact with the touch sensor device in the vicinity of receiving electrode pairs 5-12.

[0076] Figure 6 shows a method 600 for operating a touch sensor according to the parallel touch sensing embodiment described herein. It will be understood that the method 600 does not need to be performed in the order shown, and that each step may be performed in parallel or simultaneously unless otherwise specified.

[0077] In stage 602, the processing system 110, for example, the sensor circuit 104, drives the transmitting electrode with a sensing signal. For example, relating to Figure 3, the processing system 110 drives the transmitting positive electrode with a positive polarity sensing signal and drives the transmitting negative electrode with a sensing signal of the opposite polarity. As mentioned above, the negative polarity sensing signal may be, for example, the inverse signal of the positive polarity sensing signal, or it may be a positive polarity sensing signal made negative.

[0078] In stage 604, the processing system 110 reads the result signal from the differential pair of receiving electrodes. The differential pair may be read simultaneously, sequentially, or in any other order. Reading the result signal may include the application of noise reduction techniques such as ADNS.

[0079] In stage 606, the signal strength from each differential pair is determined. The signal strength may be determined, for example, by combining the signals read from the receiving positive and receiving negative terminals of each differential pair. As a specific example, for each differential pair, the result signal from the receiving negative terminal may be subtracted from the result signal of the adjacent receiving positive terminal, or vice versa. As mentioned above, subtracting the result signal from one differential pair from the other differential pair reduces noise by removing (subtracting) noise from the result signal.

[0080] In stage 608, the processing system 110 determines whether the object is in proximity to one or more areas of the touch sensor. For example, if the differential result signals from the differential pair at the corresponding position exceed a threshold, it is determined that the object is in proximity to a specific area of ​​the touch sensor.

[0081] The process 600 may be repeated across multiple capacitance frames. Furthermore, as described in relation to Figure 3, the process 600 may also include shifting the transmitting and receiving electrodes to the left or right to facilitate the detection of input objects in areas such as dead spots within the detection pattern.

[0082] Herein, the method and system can be used to more efficiently implement functions and features such as dose mode. Dose mode is a low-power state used, for example, to conserve power. In conventional technology, two sensing signal bursts may be required to detect a touch in order to return from dose mode. As reflected in the method and system described in relation to Figures 3 to 6, this embodiment can detect a touch in a single burst, and the detected touch can be used to return the electronic device from low-power mode. As mentioned above, further power savings can be achieved by using a system and method that can be implemented using only a subset of the total number of electrodes constituting the touch sensor.

[0083] Considering the above, it will be understood that exemplary embodiments of this disclosure can be implemented in a manner that minimizes the effects of noise, provides accurate detection of input objects of various sizes, and minimizes power consumption.

[0084] All references cited herein, including publications, patent applications, and patents, are incorporated herein by reference to the same extent as they are incorporated in whole, as if they were listed herein, with each reference being shown to be incorporated individually and specifically by reference.

[0085] In the context describing the present invention (particularly in the context of the claims), the terms “one” and “one,” this and “at least one,” and similar referents are to be interpreted as including both singular and plural forms, unless otherwise specified herein or unless the context clearly contradicts this interpretation. When the term “at least one” is followed by a list of one or more items (for example, “at least one of A and B”), unless otherwise specified herein or unless the context clearly contradicts this interpretation, it is to be interpreted as meaning one item selected from the listed items (A or B), or any combination of two or more listed items (A and B). The terms “comprising,” “having,” “including,” and “containing” are to be interpreted as open-ended terms (i.e., “including, but not limited to.”) unless otherwise specified herein. The descriptions of value ranges in this specification are intended to serve as a convenient way to refer individually to each individual value within the range, unless otherwise specified herein, and each individual value is incorporated into the specification as if it were individually described herein.

[0086] All methods described herein may be carried out in any suitable order, unless otherwise specified herein or unless the context clearly contradicts it. All examples or exemplary terms provided herein (e.g., "etc.") are intended solely to provide a clearer description of the invention and, unless otherwise claimed, do not limit the scope of the invention. No term used herein should be construed as indicating that an unclaimed element is essential for carrying out the invention.

[0087] This specification describes exemplary embodiments. Those skilled in the art will readily understand, by reading the above description, how these exemplary embodiments can be modified. The inventors expect that those skilled in the art will adopt such modifications as appropriate, and the invention is intended to be carried out in ways different from those specifically described herein. Therefore, the invention includes, to the extent permitted by applicable law, all modifications and equivalents of the subject matter described in the claims appended herein. Furthermore, unless otherwise stated herein, or unless clearly contradicted by the context, any combination of any possible modifications of the above elements is encompassed within the invention.

Claims

1. Multiple transmitting electrodes, Multiple receiving electrodes arranged as differential pairs, Sensor circuit and Equipped with, The plurality of transmitting electrodes are A first subset of transmitting positive electrodes driven by a positive polarity sensing signal, A second subset of the transmitting negative electrode driven by a negative polarity sensing signal, Equipped with, Each of the first subset of the transmitting positive electrodes is spatially alternating with one of the transmitting negative electrodes in the second subset of the transmitting negative electrodes. Each of the differential pairs is A receiving positive electrode coupled with at least one of the transmitting positive electrodes of the first subset, A receiving negative electrode coupled with at least one of the transmitting negative electrodes of the second subset, Equipped with, The sensor circuit supplies the positive polarity sensing signal and the negative polarity sensing signal, receives a first result signal from the receiving positive electrode, and receives a second result signal from the receiving negative electrode. The first result signal and the second result signal are combined to reduce noise. Touch sensor.

2. The negative polarity sensing signal is the inverse signal of the positive polarity sensing signal. The touch sensor according to claim 1.

3. One or more transmitting electrodes among the plurality of transmitting electrodes and one or more receiving electrodes among the plurality of receiving electrodes have different lengths from another one or more transmitting electrodes among the plurality of transmitting electrodes and another one or more receiving electrodes among the plurality of receiving electrodes. The touch sensor according to claim 1.

4. The plurality of transmitting electrodes and the plurality of receiving electrodes have the same length. The touch sensor according to claim 1.

5. The second result signal is subtracted from the first result signal to form a differential signal. The touch sensor according to claim 1.

6. The presence of an input object is determined by comparing the differential signal with a threshold value. The touch sensor according to claim 5.

7. The total number of the first subset of the transmitting positive electrodes is equal to the total number of the second subset of the transmitting negative electrodes. The touch sensor according to claim 1.

8. The difference between the total number of transmitting positive electrodes in the first subset and the total number of transmitting negative electrodes in the second subset is 1. The touch sensor according to claim 1.

9. The plurality of transmitting electrodes and the plurality of receiving electrodes operate in transcapacitive sensing mode. The touch sensor according to claim 1.

10. One or more of the plurality of transmitting electrodes are converted into receiving electrodes, and one or more of the plurality of receiving electrodes are converted into a receiving electrode or transmitting electrode with the opposite polarity. The touch sensor according to claim 1.

11. The display and Touch sensor and Processing system and, Equipped with, The aforementioned touch sensor is Multiple transmitting electrodes, Multiple receiving electrodes arranged as differential pairs, Equipped with, The plurality of transmitting electrodes are A first subset of transmitting positive electrodes driven by a positive polarity sensing signal, A second subset of the transmitting negative electrode driven by a negative polarity sensing signal, Equipped with, Each of the first subset of the transmitting positive electrodes is spatially alternating with one of the transmitting negative electrodes in the second subset of the transmitting negative electrodes. Each of the differential pairs is A receiving positive electrode coupled with at least one of the transmitting positive electrodes of the first subset, A receiving negative electrode coupled with at least one of the transmitting negative electrodes of the second subset, Equipped with, The processing system transmits the positive polarity sensing signal and the negative polarity sensing signal, receives a first result signal from the receiving positive electrode, and receives a second result signal from the receiving negative electrode. The first result signal and the second result signal are combined to reduce noise. Input device.

12. One or more transmitting electrodes among the plurality of transmitting electrodes and one or more receiving electrodes among the plurality of receiving electrodes have different lengths from another one or more transmitting electrodes among the plurality of transmitting electrodes and another one or more receiving electrodes among the plurality of receiving electrodes. The input device according to claim 11.

13. The second result signal is subtracted from the first result signal to form a differential signal, and the presence of an input object is determined by comparing the differential signal with a threshold. The input device according to claim 11.

14. The difference between the total number of transmitting positive electrodes in the first subset and the total number of transmitting negative electrodes in the second subset is 1 or less. The input device according to claim 11.

15. One or more of the plurality of transmitting electrodes are converted into receiving electrodes, and one or more of the plurality of receiving electrodes are converted into a receiving electrode or transmitting electrode with the opposite polarity. The input device according to claim 11.

16. Driving multiple transmitting positive electrodes with a positive polarity sensing signal, Driving multiple transmitting negative electrodes with a negative polarity sensing signal, Receiving a first result signal from multiple receiving positive electrodes, Receiving a second result signal from multiple receiving negative electrodes, The second result signal and the first result signal are combined, Based on the synthesized result signal, the presence of the input object is determined, Includes, The plurality of transmitting positive electrodes are spatially alternating with the transmitting negative electrodes. Each of the receiving positive electrodes is coupled with at least one of the plurality of transmitting positive electrodes. Each of the receiving negative electrodes is coupled with at least one of the plurality of transmitting negative electrodes. Transcapacitive sensing method.

17. Combining the second result signal and the first result signal is The second result signal is subtracted from the first result signal to generate a differential signal. including, The method according to claim 16.

18. The plurality of transmitting positive electrodes are driven simultaneously with the plurality of transmitting negative electrodes. The method according to claim 16.

19. The presence of an input object is determined by comparing the differential signal with a threshold value. Further including, The method according to claim 17.

20. One or more of the plurality of receiving positive electrodes or one or more of the plurality of receiving negative electrodes are driven by a detection signal, Receiving a result signal from one or more of the plurality of positive transmitting electrodes or one or more of the plurality of negative transmitting electrodes, Further including, The method according to claim 16.

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