WO2013179422A1 - Système de panneau tactile et dispositif électronique - Google Patents

Système de panneau tactile et dispositif électronique Download PDF

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Publication number
WO2013179422A1
WO2013179422A1 PCT/JP2012/063963 JP2012063963W WO2013179422A1 WO 2013179422 A1 WO2013179422 A1 WO 2013179422A1 JP 2012063963 W JP2012063963 W JP 2012063963W WO 2013179422 A1 WO2013179422 A1 WO 2013179422A1
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WIPO (PCT)
Prior art keywords
touch panel
touch
signal
difference
unit
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PCT/JP2012/063963
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English (en)
Japanese (ja)
Inventor
宮本　雅之
眞一 芳田
西岡　明
湯元　学
高濱　健吾
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シャープ株式会社
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Priority to PCT/JP2012/063963 priority Critical patent/WO2013179422A1/fr
Priority to JP2014518153A priority patent/JP5845344B2/ja
Publication of WO2013179422A1 publication Critical patent/WO2013179422A1/fr

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    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F3/00—Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
    • G06F3/01—Input arrangements or combined input and output arrangements for interaction between user and computer
    • G06F3/03—Arrangements for converting the position or the displacement of a member into a coded form
    • G06F3/041—Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
    • G06F3/0416—Control or interface arrangements specially adapted for digitisers
    • G06F3/0418—Control or interface arrangements specially adapted for digitisers for error correction or compensation, e.g. based on parallax, calibration or alignment
    • G06F3/04184—Synchronisation with the driving of the display or the backlighting unit to avoid interferences generated internally
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F3/00—Input arrangements for transferring data to be processed into a form capable of being handled by the computer; Output arrangements for transferring data from processing unit to output unit, e.g. interface arrangements
    • G06F3/01—Input arrangements or combined input and output arrangements for interaction between user and computer
    • G06F3/03—Arrangements for converting the position or the displacement of a member into a coded form
    • G06F3/041—Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
    • G06F3/044—Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means by capacitive means
    • G06F3/0445—Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means by capacitive means using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer

Definitions

  • the present invention relates to a touch panel system and an electronic apparatus including the touch panel system, and more particularly to a touch panel system and an electronic apparatus that can reliably and effectively remove (cancel) noise generated by a display device or the like. .
  • touch panel systems are rapidly being installed in various electronic devices such as mobile information devices such as smartphones and vending machines such as ticket vending machines.
  • Such a touch panel system usually has a structure in which a touch panel is laminated on the upper part (front surface) of the display device. For this reason, the sensor provided on the touch panel is susceptible to not only noise such as a clock generated in the display device but also other external noise. Such noise leads to a decrease in detection sensitivity of the touch operation.
  • Patent Document 1 describes a touch panel system (coordinate input device) with such noise countermeasures.
  • the touch panel system of Patent Document 1 includes a noise processing unit in order to remove noise.
  • FIG. 19 is a block diagram illustrating the noise processing unit 100 provided in the touch panel system of Patent Document 1.
  • the noise processing unit 100 includes a filter unit 101, a logic inversion unit 102, and an addition unit 103.
  • the filter unit 101 receives an output signal (analog signal) from a sensor provided on a touch panel (not shown). Further, the filter unit 101 extracts an AC signal component included in the input signal as a noise signal.
  • the logic inversion unit 102 inverts the phase of the extracted noise signal by 180 degrees.
  • the adding unit 103 adds a noise signal whose phase is inverted by 180 degrees to the input signal including the noise signal input to the filter unit 101.
  • the noise signal extracted by the filter unit 101 is inverted, and the inverted signal is added to the input signal (analog signal) from the sensor. That is, an inverted signal having the same level as the noise component is added to the noise component included in the input signal from the sensor. Thereby, the noise superimposed on the input signal from the sensor is canceled. Therefore, it is possible to reduce the influence of noise included in the input signal from the sensor.
  • the touch panel system of Patent Document 1 handles an AC signal component included in an input signal from a sensor as noise.
  • the AC signal is extracted by the filter unit 101 and then the phase is inverted by 180 degrees by the logic inversion unit 102.
  • the adder 103 adds the inverted signal to the input signal including the AC signal component.
  • the process of extracting the AC signal component in the filter unit 101 is the most important for noise processing.
  • Patent Document 1 does not disclose the configuration of the filter unit 101 in detail. For this reason, it is unclear to what extent the touch panel system of Patent Document 1 can remove noise.
  • Patent Document 1 an AC signal component included in an analog signal is treated as noise. That is, in the touch panel system of Patent Document 1, it is assumed that only impulse noise is basically removed, and noise other than impulse noise is excluded from removal. For this reason, it is not possible to reliably cancel various noises other than impulse noise.
  • the present invention has been made in view of the above-described conventional problems, and its purpose is to reliably remove various types of noise, reduce power consumption, and improve detection sensitivity of touch operations. It is providing the touch panel system and electronic device which can be used.
  • a touch panel system includes a plurality of sense lines and a plurality of drive lines that are provided so as to intersect with the sense lines and form capacitance between the sense lines.
  • a touch line controller that drives the drive lines in parallel
  • a touch panel controller that processes the signals of the sense lines to generate touch information, and an effective area on the touch panel based on the touch information.
  • An area setting unit for setting, and the touch panel controller is calculated by a subtracting unit that calculates a difference between signals of the adjacent sense lines, a code sequence that drives the drive lines in parallel, and the subtracting unit.
  • a decoding unit that calculates the difference distribution of the capacitance, and a touch detection unit that generates the touch information based on the difference distribution of the capacitance calculated by the decoding unit.
  • the effective area set on the touch panel is updated based on the touch information to set a new effective area, and the drive line drive circuit passes through the currently set effective area.
  • At least one of a first operation for selectively driving the drive line and a second operation for the touch panel controller to selectively process the signal of the sense line passing through the currently set effective area is performed. It is characterized by being.
  • the subtracting unit acquires a difference signal value between adjacent sense lines. That is, a difference between adjacent sense lines having higher noise correlation is obtained. Thereby, the noise component is removed from the output signal of the sense line, and the original signal of the touch operation is extracted. Therefore, various types of noise reflected on the touch panel can be reliably removed (cancelled).
  • a touch panel is driven in parallel and a decoding part decodes the difference value of the electrostatic capacitance calculated in the subtraction part.
  • the electrostatic capacity signal is obtained by multiplying the code length (N times), the signal strength of the electrostatic capacity increases without depending on the number of drive lines.
  • the signal intensity is the same as that of the conventional method, the number of drive lines can be reduced, and the power consumption can be reduced.
  • the drive line it is possible to prevent the drive line from being driven unnecessarily by the first operation. For this reason, it is possible to reduce the power consumption for driving the drive line, and it is possible to suppress the generation of noise and improve the detection sensitivity of the touch operation. In addition, it is possible to improve the detection accuracy of the touch position by driving the drive line in a limited manner. Moreover, unnecessary signal processing can be prevented by the second operation. Therefore, it is possible to reduce power consumption for signal processing. In addition, the detection accuracy of the touch position can be improved by limitedly processing the signal of the sense line passing through the effective area.
  • a sense line Sn selected from the sense lines and two sense lines (sense line Sn + 1, sense line Sn-1) adjacent to the sense line Sn
  • a first difference ((Sn + 1) ⁇ Sn) that is a difference between the signal of the sense line Sn + 1 and the signal of the sense line Sn + 1, or a second difference that is a difference between the signal of the sense line Sn and the signal of the sense line Sn ⁇ 1.
  • a switch for switching the signal of the sense line input to the subtracting unit may be further provided so that the difference (Sn ⁇ (Sn ⁇ 1)) is calculated.
  • the switch includes two terminals, and one terminal is selected, and the code series for driving the drive lines in parallel is the drive line shown below.
  • d 1 (d 11 , d 12 ,..., d 1N )
  • d 2 (d 21 , d 22 ,..., d 2N )
  • ⁇ ⁇ d M (d M1 , d M2 ,..., d MN )
  • the decoding unit may calculate an inner product of the code sequence for driving the drive lines in parallel and the difference output sequence corresponding to the code sequence.
  • the subtracting unit includes a first AD converting unit that converts an analog signal into a digital signal, and the subtracting unit converts the analog signal obtained from the sense line into the first AD converting unit.
  • the first difference and the second difference may be calculated by calculating a difference between the digital signals after the digital signal is converted by the unit.
  • noise can be removed by performing a subtraction process after converting an analog signal output from the touch panel into a digital signal.
  • the subtraction unit includes a second AD conversion unit that converts an analog signal into a digital signal, and the subtraction unit calculates a difference between the analog signals obtained from the sense lines.
  • the first difference and the second difference may be calculated by converting the difference between the analog signals into a digital signal by the second AD converter.
  • the analog signal output from the touch panel can be subtracted from the analog signal and then converted into a digital signal to remove noise.
  • the subtractor calculates a difference between analog signals obtained from the adjacent sense lines, thereby calculating the first difference and the second difference. It is preferable to provide.
  • the analog signal output from the touch panel can be subtracted with the fully differential amplifier as it is, and then converted into a digital signal to remove noise.
  • a non-touch operation information storage unit that stores the difference distribution of the capacitance calculated by the decoding unit during a non-touch operation, and the static information calculated by the decoding unit during a touch operation.
  • a calibration unit that subtracts the capacitance difference distribution during the non-touch operation stored in the non-touch operation information storage unit from the capacitance difference distribution.
  • the non-touch operation time information storage unit stores the capacitance difference distribution during the non-touch operation decoded by the decoding unit.
  • a calibration part subtracts the difference distribution of the electrostatic capacity at the time of non-touch operation memorize
  • the touch detection unit determines presence / absence of a touch operation based on a comparison between a difference between signals of adjacent sense lines calculated by the subtraction unit and a positive and negative threshold. May be.
  • the touch detection unit determines the presence / absence of the touch operation based on the difference between the signals of the adjacent sense lines from which the noise signal has been removed. Therefore, the presence / absence of a touch operation can be accurately determined.
  • the touch detection unit may calculate the difference between the capacitances based on a comparison between a difference between signals of adjacent sense lines calculated by the subtraction unit and a positive and negative threshold.
  • the touch information may be generated by creating an increase / decrease table in which the distribution is ternarized and converting the increase / decrease table into a binary image.
  • the difference between the signals of the adjacent sense lines from which the noise signal has been removed is input to the touch detection unit.
  • the touch detection unit uses the difference between the signals of the adjacent sense lines and the comparison between the positive and negative threshold values stored in the touch detection unit to increase or decrease the difference distribution of the signals of each sense line in three values. Create a table. Further, the touch detection unit binarizes the increase / decrease table, thereby converting the increase / decrease table into a binary image. Thereby, touch position candidates are extracted from the converted binary image. Therefore, by recognizing touch information (touch size, touch position, etc.) based on this binary image, it is possible to more accurately recognize touch information in addition to the presence or absence of a touch operation.
  • the touch panel system further includes an adding unit that adds the difference calculated by the subtracting unit, the touch panel includes at least one sub sense line, and the subtracting unit includes the sub sense line and the sub sense line.
  • a third difference that is a difference from a sense line adjacent to the sense line is further calculated, and the adding unit adds the first difference, the second difference, and the third difference. preferable.
  • the sense line and the sub sense line are provided in the same plane (on the same plane) on the touch panel.
  • various output signals of the sense line and the sub-sense line include various noise signals reflected on the touch panel.
  • the subtracting unit calculates a difference between the output signal of the sense line including the signal by the touch operation and the noise signal, and the output signal of the sub sense line including the noise signal.
  • the noise component is removed from the output signal of the sense line, and the original signal of the touch operation is extracted. Therefore, various types of noise reflected on the touch panel can be reliably removed (cancelled).
  • the sub-sense line signal (noise signal) is also removed from the output signal of each sense line. Therefore, noise can be removed more reliably.
  • the sense line and the sub-sense line are adjacent to each other, that is, the sense line and the sub-sense line are arranged closest to each other, and the sense line and the sub-sense line are arranged under substantially the same conditions. It becomes a state. For this reason, the noise signal value included in the output signal of the sub sense line can be regarded as the same as the noise signal value included in the output signal of the sense line. Thereby, the noise component reflected on the touch panel can be more reliably removed by the subtraction processing by the subtraction unit. Therefore, the detection sensitivity of the touch operation can be further increased.
  • the subtracting unit includes a third AD converting unit that converts an analog signal into a digital signal, and the subtracting unit outputs the analog signal obtained from the sense line or the sub-sense line. After converting into a digital signal by the third AD converter, the first difference, the second difference, and the third difference may be calculated by calculating a difference between the digital signals.
  • noise can be removed by performing a subtraction process after converting an analog signal output from the touch panel into a digital signal.
  • the subtraction unit includes a fourth AD conversion unit that converts an analog signal into a digital signal, and the subtraction unit is a difference between analog signals obtained from the sense line or the sub-sense line. Then, the difference between the analog signals is converted into a digital signal by the fourth AD conversion unit, thereby calculating the first difference, the second difference, and the third difference. Good.
  • the analog signal output from the touch panel can be subtracted from the analog signal and then converted into a digital signal to remove noise.
  • the subtracting unit calculates a difference between analog signals obtained from the sense line or the sub-sense line to thereby calculate the first difference, the second difference, and the third difference. It is preferable to further include a fully differential amplifier for calculating
  • the analog signal output from the touch panel can be subtracted with the fully differential amplifier as it is, and then converted into a digital signal to remove noise.
  • the fully differential amplifier has a rail-to-rail operation in an input common mode voltage range.
  • a fully differential amplifier capable of rail-to-rail operation.
  • the fully differential amplifier can operate in a voltage range from the power supply voltage (Vdd) to GND. Therefore, the problem of output saturation does not occur in the output signal from the fully differential amplifier.
  • the addition unit may advance the addition process in the order of the distance from the sub sense line and use the addition result for the next addition process.
  • the adder sequentially advances the addition process in a direction away from the sub-sense line while using the addition result. Therefore, the addition processing speed can be increased.
  • the sub sense line may not detect a touch operation of the touch panel.
  • the output signal of the sub sense line does not include a signal due to the touch operation.
  • the signal value of the touch operation is not reduced by the subtraction process of the subtraction unit. That is, the noise component is removed without reducing the touch operation signal detected on the sense line. Therefore, the detection sensitivity of the touch operation can be further increased.
  • the sub sense line may be provided in a region where the touch operation is not performed on the touch panel.
  • the sub sense line is provided avoiding an area (touch area) where the user performs a touch operation. For this reason, the sub-sense line detects noise reflected on the touch panel without the user performing a touch operation, but does not detect a signal due to the touch operation. Therefore, it is possible to reliably avoid the sub-sense line from detecting the touch operation.
  • the output signal of the sub sense line does not include a signal due to the touch operation.
  • the signal value of the touch operation is not reduced by the subtraction process of the subtraction unit. That is, the noise component is removed without reducing the touch operation signal detected on the sense line. Therefore, the detection sensitivity of the touch operation can be further increased.
  • the drive line drive circuit gives the unique code sequence set for each drive line to each of the drive lines passing through the effective area, and It is preferable not to give the code sequence to each of the drive lines that do not pass.
  • the touch panel controller can easily identify the fluctuations in the signal of the sense line caused by the touch operation.
  • the touch panel controller further includes an amplification unit that selectively amplifies the signal of the sense line passing through the effective region.
  • the touch panel controller further includes a signal acquisition unit that selectively acquires the signal of the sense line passing through the effective area and outputs the signal in a time division manner.
  • the area setting unit sets a new effective area including a touch position which is a part of the touch information.
  • the area setting unit can set a new effective area that is likely to include the touch position next.
  • the area setting unit sets a new effective area having a size corresponding to a moving speed of a touch position which is a part of the touch information.
  • the area setting unit can set a new effective area that is likely to include the touch position next.
  • the area setting unit sets a new effective area that is the entire surface of the touch panel when the touch panel controller does not detect a touch operation.
  • the touch panel controller can detect the touch position no matter which position on the touch panel becomes the touch position next time.
  • the region setting unit sets a new effective region based on a touch position that is a part of the touch information, and the second mode.
  • the area setting unit may continuously set a new effective area that is the entire surface of the touch panel.
  • the first mode for reducing power consumption and improving the detection sensitivity of the touch operation and the touch position can be detected from the entire surface of the touch panel without omission.
  • the touch panel system can be operated in either of the second mode.
  • the area setting unit sets a new effective area based on the plurality of touch positions.
  • the area setting unit can set the effective area.
  • the area setting unit sets a new effective area based on the plurality of touch positions
  • a plurality of new effective areas corresponding to the touch positions are set. Each is preferably set.
  • an upper limit value is set for the number of new effective areas set by the area setting unit.
  • the number of valid areas that can be set by the area setting unit is limited to an upper limit value or less. For this reason, it is possible to suppress the calculation amount of the region setting unit from becoming excessive or the total area of the effective regions set by the region setting unit from becoming too large.
  • the area setting unit sets a new effective area that becomes the entire surface of the touch panel at every predetermined timing.
  • the touch operation is performed at another place on the touch panel. Even if it is performed, an effective area that is the entire surface of the touch panel is set at a predetermined timing, so that the touch position can be detected by the touch panel controller.
  • the code sequence may be an orthogonal sequence or an M sequence.
  • the touch panel system according to the present invention further includes a display device, and the touch panel is provided on the front surface of the display device.
  • the display device is preferably a liquid crystal display, a plasma display, an organic EL display, or a field emission display.
  • the display device is configured from various displays that are frequently used in everyday electronic equipment. Therefore, a highly versatile touch panel system can be provided.
  • an electronic device includes any one of the touch panel systems.
  • the touch panel system includes a subtracting unit that receives a signal from the main sensor unit and calculates a difference between signals of adjacent sense lines. That is, the subtracting unit obtains a differential signal value between adjacent sense lines with higher noise correlation. Thereby, the noise component is removed from the output signal of the main sensor unit, and the original signal of the touch operation is extracted. Therefore, it is possible to reliably remove (cancel) various types of noise reflected on the touch panel.
  • the effective area which is the area where the touch position is to be detected, is limitedly set in the touch panel based on the detected touch position. Therefore, avoiding useless detection can reduce power consumption and improve detection sensitivity of a touch operation.
  • FIG. 10 is a diagram illustrating processing necessary to obtain the same sensitivity as that of the driving touch panel of FIG. 10 by the driving touch panel of FIG. 9.
  • the touch panel system provided with the orthogonal sequence drive-type touch panel.
  • FIG. 17 is a circuit diagram illustrating an example of a fully differential amplifier in the touch panel system of FIG. 16. It is the schematic which shows the basic composition of another touch panel system which concerns on this invention. It is a block diagram which shows the noise process part provided in the touchscreen system of patent document 1.
  • FIG. It is the schematic which shows the basic composition of another touch panel system which concerns on this invention.
  • FIG. 21 is a flowchart showing basic processing of the touch panel system of FIG. 20. It is the schematic which shows the basic composition of another touch panel system which concerns on this invention. It is the schematic which shows the basic composition of another touch panel system which concerns on this invention. It is the schematic which shows the basic composition of another touch panel system which concerns on this invention. It is the schematic which shows the basic composition of another touch panel system which concerns on this invention. It is the schematic which shows the basic composition of another touch panel system which concerns on this invention.
  • FIG. 1 is a schematic diagram showing a basic configuration of a touch panel system 1 according to an embodiment of the present invention.
  • the touch panel system 1 includes a display device 2, a touch panel 3, a touch panel controller 4, and a drive line drive circuit 5, and has a noise canceling function.
  • the side which a user utilizes is demonstrated as a front surface (or upper direction).
  • the display device 2 includes a display screen (display unit) (not shown). Various icons for operation, character information corresponding to user operation instructions, and the like are displayed on the display screen.
  • the display device 2 includes, for example, a liquid crystal display, a plasma display, an organic EL display, a field emission display (FED), and the like. These displays are frequently used in everyday electronic devices, and a highly versatile touch panel system 1 is configured.
  • the display device 2 may have any configuration and is not particularly limited.
  • the touch panel 3 inputs various operation instructions by the user touching (pressing) the surface of the touch panel 3 with a finger or a pen.
  • the touch panel 3 is laminated on the front surface (upper part) of the display device 2 so as to cover the display screen.
  • the touch panel 3 includes two sensors (one main sensor 31 and one sub sensor 32) provided on the same surface (in the same surface).
  • the main sensor 31 and the sub sensor 32 are provided adjacent to each other.
  • the main sensor 31 and the sub sensor 32 are both capacitive sensors.
  • the touch panel 3 on which the capacitive sensor is installed has an advantage of high transmittance and durability.
  • the main sensor (main sensor unit) 31 is provided in a touch-operated area (touch area) on the touch panel 3 and detects a touch operation of the touch panel 3 by the user.
  • the touch operation includes a double click operation, a slide operation, a single click operation, a drag operation, and the like.
  • the main sensor 31 includes a sense line 33 made of a linear electrode. One end of the sense line 33 is connected to the touch panel controller 4. Thereby, the signal detected by the main sensor 31 is output to the touch panel controller 4 via the sense line 33. That is, a signal corresponding to the touch operation detected by the main sensor 31 is output to the touch panel controller 4.
  • the sub sensor (sub sensor unit) 32 detects a noise component reflected on the touch panel 3.
  • the sub sensor 32 is provided in a non-touch area on the touch panel 3 (non-touch area). For this reason, the sub sensor 32 detects various noises generated in the touch panel system 1 without the user touching the touch operation.
  • the sub sensor 32 does not detect a signal corresponding to the touch operation. That is, the sub sensor 32 detects noise generated on the touch panel 3 without the user touching the touch operation.
  • the sub sensor 32 includes a sub sense line 34 formed of a linear electrode.
  • the sub sense line 34 is parallel to the sense line 33 (extends in the same direction as the sense line 33).
  • One end of the sub sense line 34 is connected to the touch panel controller 4.
  • the signal detected by the sub sensor 32 is output to the touch panel controller 4 via the sub sense line 34.
  • the touch panel 3 includes a drive line 35 that intersects the sense line 33 and the sub-sense line 34 so as to be orthogonal to each other.
  • the drive line 35 is made of a linear electrode. Capacitance is formed at the intersection of the sense line 33 or the sub-sense line 34 and the drive line 35. That is, electrostatic capacitances are formed between the sense line 33 and the drive line 35 and between the sub sense line 34 and the drive line 35, respectively.
  • the drive line 35 is connected to a drive line drive circuit (sensor drive unit) 5, and a potential is applied to the drive line 35 at a constant period when the touch panel system 1 is activated.
  • the sense line 33, the sub sense line 34, and the drive line 35 can all be formed from a transparent wiring material such as ITO (Indium Thin Oxide). It can be said that the sense line 33, the sub sense line 34, and the drive line 35 are sensor electrodes in the touch panel 3.
  • ITO Indium Thin Oxide
  • the drive line 35 is provided on a transparent substrate or a transparent film (not shown). Further, the drive line 35 is covered with an insulating layer (not shown). On the insulating layer, a sense line 33 and a sub sense line 34 are provided. As described above, the sense line 33 or the sub sense line 34 and the drive line 35 are insulated from each other through the insulating layer and capacitively coupled. The sense line 33 and the sub sense line 34 are covered with a protective layer (not shown). That is, in the touch panel 3, the protective layer is disposed on the foremost side (user side).
  • the touch panel controller 4 reads signals (data) input from the main sensor 31 and the sub sensor 32 of the touch panel 3. Since the touch panel system 1 includes a capacitance type sensor, the touch panel controller 4 detects the capacitance generated on the touch panel 3. Specifically, the touch panel controller 4 detects a change in capacitance between the sense line 33 and the drive line 35 and a change in capacitance between the sub sense line 34 and the drive line 35.
  • the touch panel controller 4 includes a subtraction unit 41, a coordinate detection unit 42 (touch detection unit), and a CPU 43.
  • the subtractor 41 has an input terminal (input terminal for main sensor output) for receiving a signal output from the main sensor 31 and an input terminal (sub sensor output) for receiving a signal output from the sub sensor 32. Input terminal).
  • the subtracting unit 41 subtracts the signal input to the sub sensor output input terminal from the signal input to the main sensor output input terminal.
  • the signal subjected to the subtraction process by the subtraction unit 41 is output to the coordinate detection unit 42.
  • the signal input to the subtracting unit 41 may be a digital signal or an analog signal. That is, the input signal to the subtraction unit 41 may be a signal corresponding to the configuration of the subtraction unit 41.
  • the coordinate detection unit 42 detects the presence / absence information of the touch operation based on the signal subjected to the subtraction process by the subtraction unit 41. For example, when the output signal value from the subtraction unit 41 is equal to or greater than a predetermined threshold, the coordinate detection unit 42 outputs a signal indicating that the touch operation is “present” to the CPU 43. In the touch panel system 1, since the number of main sensors 31 is single, the coordinate detection unit 42 detects presence / absence information of a touch operation. On the other hand, when there are a plurality of main sensors 31, the coordinate detection unit 42 also detects the coordinate value of the touch position of the user.
  • the CPU 43 captures information output from the coordinate detection unit 42 at regular intervals, and outputs the information to the display device 2 according to the captured information.
  • the drive line drive circuit 5 is connected to the drive line 35, and applies a potential to the drive line 35 at a constant cycle when the touch panel system 1 is activated.
  • the touch panel system 1 detects the presence or absence of a touch operation based on a change in capacitance detected by the touch panel controller 4.
  • the touch panel 3 is bonded to the front surface (user side) of the display device 2.
  • the touch panel system 1 is susceptible to not only noise such as a clock generated by the display device 2 but also other external noise.
  • the detection sensitivity of the touch operation decreases.
  • the touch panel system 1 includes a sub sensor 32 and a subtraction unit 41 as a countermeasure for removing such noise. Based on FIG. 2, the noise cancellation process of the touch panel system 1 is demonstrated.
  • FIG. 2 is a flowchart showing a noise canceling process that is a basic process of the touch panel system 1.
  • both the main sensor 31 and the sub sensor 32 output signals to the subtracting unit 41.
  • noise such as a clock generated by the display device 2 and other external noise are reflected on the touch panel 3.
  • the main sensor 31 and the sub sensor 32 detect various noise components. That is, in the output signal from the main sensor 31, a noise signal (noise component) is added to the original signal of the touch operation.
  • the sub sensor 32 does not detect a touch operation. For this reason, the output signal from the sub sensor 32 includes a noise signal (noise component), but does not include a touch operation signal (F201).
  • the main sensor 31 and the sub sensor 32 are provided in the same plane and adjacent to each other. For this reason, the noise signal value included in the output signal of the main sensor 31 and the noise signal value included in the output signal of the sub sensor 32 can be regarded as basically the same value. Therefore, the subtracting unit 41 present in the touch panel controller 4 executes a process of subtracting the input signal (signal value) from the sub sensor 32 from the input signal (signal value) from the main sensor 31 (F202). That is, the subtracting unit 41 calculates a difference between the sense line 33 and the sub sense line 34. Thereby, the noise signal is removed from the output signal from the main sensor 31. Therefore, the original signal value of the touch operation generated by the touch operation can be obtained.
  • the signal thus subtracted (the original signal for the touch operation) is output to the coordinate detection unit 42 present in the touch panel controller 4 (F203).
  • the original signal for the touch operation is output to the coordinate detection unit 42.
  • the coordinate detection unit 42 detects the presence / absence of a touch operation by signal processing inherent to the touch operation. Therefore, it is possible to suppress a decrease in detection sensitivity (such as detection accuracy of presence / absence of touch operation) of the coordinate detection unit 42.
  • the subtracting unit 41 calculates the difference between the sense line 33 and the sub sense line 34, and cancels the noise component from the input signal from the sense line 33 including various noise components. That is, the subtraction unit 41 removes the noise signal from the input signal from the sense line 33 and extracts the original signal generated by the touch operation. Accordingly, it is possible to provide the touch panel system 1 that can reliably cancel various types of noise.
  • FIG. 3 is a diagram illustrating a waveform of a signal processed by the subtracting unit 41 in the touch panel system 1.
  • 3A shows an output signal from the main sensor 31
  • FIG. 3B shows an output signal from the sub sensor 32
  • FIG. 3C shows a signal processed by the subtracting unit 41.
  • Each signal shown in FIG. 3 is a signal when the user performs a touch operation.
  • the capacity of the main sensor 31 that detects the touch operation increases ((a) in FIG. 3). That is, the output signal value from the main sensor 31 (sense line 33) increases.
  • various noise signals noise such as clock generated by the display device 2 and external noise
  • the capacity of the sub sensor 32 does not increase depending on the touch operation. That is, the output signal from the sub sensor 32 does not include a touch operation signal, but includes a noise component reflected on the touch panel 3 ((b) in FIG. 3).
  • the subtracting unit 41 subtracts the output signal from the sub sensor 32 from the output signal from the main sensor 31 (the signal value in FIG. 3A-the signal value in FIG. 3B). By this subtraction process, the noise component output from the sub sensor 32 is removed from the output signal from the main sensor 31 as shown in FIG. Therefore, the original signal of the touch operation generated by the touch operation can be obtained. Furthermore, since the original signal of the touch operation is input to the coordinate detection unit 42, the detection accuracy of the touch operation does not decrease.
  • the main sensor 31 and the sub sensor 32 are provided in the same plane (on the same plane) on the touch panel 3.
  • any output signal from the main sensor 31 and the sub sensor 32 includes various noise signals reflected on the touch panel 3.
  • the subtracting unit 41 calculates a difference between the output signal from the main sensor 31 including the signal by the touch operation and the noise signal and the output signal from the sub sensor 32 including the noise signal.
  • the noise component is removed from the output signal of the main sensor 31, and the original signal of the touch operation is extracted. Therefore, various types of noise reflected on the touch panel 3 can be reliably removed (cancelled).
  • the noise component to be removed is an AC signal component in a signal including the noise component.
  • various noise components are included in the output signals from the main sensor 31 and the sub sensor 32.
  • the noise component to be removed in the touch panel system 1 is not limited to the AC signal component. Therefore, the touch panel system 1 can cancel all noises reflected on the touch panel 3.
  • the sub sensor 32 may be provided on the same surface of the touch panel 3 together with the main sensor 31. Thereby, in both the main sensor 31 and the sub sensor 32, the noise component (noise signal) reflected on the touch panel 3 can be detected.
  • the sub sensor 32 is preferably configured not to detect a touch operation on the touch panel 3. According to this configuration, since the signal due to the touch operation is not detected by the sub sensor 32, the output signal from the sub sensor 32 does not include the signal due to the touch operation. Thereby, the signal value of the touch operation is not reduced by the subtraction process of the subtraction unit 41. That is, the noise component is removed without reducing the touch operation signal detected by the main sensor 31. Therefore, the detection sensitivity of the touch operation can be further increased.
  • the sub sensor 32 When the sub sensor 32 is provided in a region where the user on the touch panel 3 is not touch-operated (non-touch region) as in the touch panel system 1, a signal due to the touch operation is not detected by the sub sensor 32. For this reason, the sub sensor 32 detects noise reflected on the touch panel without a touch operation by the user, but does not detect a signal due to the touch operation. Therefore, it is possible to reliably avoid the sub sensor 32 from detecting the touch operation.
  • the sub sensor 32 In detecting the noise component by the sub sensor 32, the sub sensor 32 is preferably provided as close to the main sensor 31 as possible, and more preferably provided adjacent to the main sensor 31. Thereby, the main sensor 31 and the sub sensor 32 are arrange
  • the touch panel system 1 including the capacitive touch panel 3 has been described.
  • the operation principle (sensor operation method) of the touch panel 3 is not limited to the capacitance method.
  • a touch panel system including a resistive film type, infrared type, ultrasonic type, or electromagnetic inductive coupling type touch panel similarly exhibits a noise canceling function.
  • the noise canceling function is exhibited regardless of the type of the display device 2.
  • the touch panel system 1 of the present embodiment can be applied to various touch panel electronic devices.
  • electronic devices include televisions, personal computers, mobile phones, digital cameras, portable game machines, electronic photo frames, personal digital assistants (PDAs), electronic books, home appliances (microwave ovens, washing machines, etc.), Ticket vending machines, ATM (Automated Teller Machine), car navigation, etc. can be mentioned.
  • PDAs personal digital assistants
  • electronic books home appliances (microwave ovens, washing machines, etc.), Ticket vending machines, ATM (Automated Teller Machine), car navigation, etc.
  • ATM Automatic Teller Machine
  • FIG. 4 is a schematic diagram showing a basic configuration of another touch panel system 1a according to the present invention.
  • the basic configuration of touch panel system 1a is substantially the same as touch panel system 1 of the first embodiment.
  • the touch panel system 1a will be described focusing on differences from the touch panel system 1.
  • members having the same functions as those in the drawings explained in the first embodiment are given the same reference numerals and explanations thereof are omitted.
  • the touch panel system 1a is different from the touch panel system 1 in the configuration of sensors provided on the touch panel 3a. That is, the touch panel 3 a includes a main sensor group 31 a including a plurality of main sensors 31 and a sub sensor group 32 a including a plurality of sub sensors 32.
  • the touch panel system 1a detects not only the presence / absence of a touch operation by the user but also position information (coordinates) of the user's touch operation.
  • the touch panel 3a includes a main sensor group 31a and a sub sensor group 32a on the same surface (in the same surface) of the touch panel 3a.
  • the main sensor group 31a and the sub sensor group 32a are provided adjacent to each other. Both the main sensor group 31a and the sub sensor group 32a are composed of capacitive sensors.
  • the main sensor group (main sensor unit) 31a is provided in a touch-operated area (touch area) on the touch panel 3a, and detects a touch operation of the touch panel 3a by the user.
  • the main sensor group 31a is composed of a plurality of main sensors 31 arranged in a grid pattern.
  • the main sensor group 31a includes L (L is an integer of 2 or more) sense lines 33.
  • the sense lines 33 are provided in parallel to each other and at equal intervals.
  • M is an integer of 2 or more) main sensors 31 are arranged.
  • each sense line 33 is connected to the subtracting unit 41 of the touch panel controller 4.
  • the signal detected by the main sensor 31 is output to the subtracting unit 41 via each sense line 33. That is, a signal corresponding to the touch operation detected by the main sensor 31 is output to the subtraction unit 41.
  • the sub sensor group (sub sensor unit) 32a detects a noise component reflected on the touch panel 3a.
  • the sub sensor group 32a is provided in a non-touch area (non-touch area) on the touch panel 3a. For this reason, the sub sensor group 32a detects various noises generated in the touch panel system 1a without the user touching the touch operation.
  • the sub sensor group 32a does not detect a signal corresponding to a touch operation. That is, the sub sensor group 32a detects noise generated in the sensor without the user touching the touch operation.
  • the sub sensor group 32 a includes one sub sense line 34.
  • the sub sense line 34 is parallel to each sense line 33 (extends in the same direction as the sense line 33).
  • M is an integer of 2 or more) sub sensors 32 are arranged on the sub sense line 34. That is, the number of main sensors 31 arranged on each sense line 33 is the same as the number of sub sensors 32 arranged on the sub sense line 34.
  • One end of the sub sense line 34 is connected to the subtracting unit 41 of the touch panel controller 4. As a result, the signal detected by the sub sensor group 32 a is output to the subtraction unit 41 via the sub sense line 34.
  • the touch panel 3a includes M (M is an integer of 2 or more) drive lines 35 that intersect each sense line 33 and the sub sense line 34 so as to be orthogonal to each other.
  • the drive lines 35 are provided in parallel to each other and at equal intervals.
  • L L is an integer of 2 or more
  • main sensors 31 and one sub sensor 32 are arranged on each drive line 35.
  • an electrostatic capacity is formed at the intersection of each sense line 33 or sub-sense line 34 and each drive line 35. That is, electrostatic capacitances are formed between the sense lines 33 and the drive lines 35 and between the sub sense lines 34 and the drive lines 35, respectively.
  • the drive line 35 is connected to a drive line drive circuit (not shown), and a potential is applied to the drive line 35 at a constant period when the touch panel system 1a is activated.
  • the sense lines 33 and the sub sense lines 34 provided in the horizontal direction and the drive lines 35 provided in the vertical direction are arranged in a two-dimensional matrix.
  • the number, length, width, interval, and the like of the sense line 33, the sub sense line 34, and the drive line 35 can be arbitrarily set depending on the use of the touch panel system 1a or the size of the touch panel 3a.
  • FIG. 5 is a schematic diagram showing a touch panel 3b that does not include the sub sensor group 32a in the touch panel system 1a of FIG.
  • the touch panel 3b includes only the main sensor group 31a and does not include the sub sensor group 32a. That is, the touch panel 3b of FIG. 5 has a configuration before noise countermeasures. In this case, the touch panel 3b is affected by various noises. Therefore, various noise components are included in the signal output from each sense line 33, and the detection sensitivity of the touch operation is lowered.
  • the touch panel system 1a includes a sub sensor group 32a and a subtracting unit 41 as a countermeasure for removing such noise. Based on FIG. 6, the noise cancellation processing of the touch panel system 1a will be described.
  • FIG. 6 is a flowchart showing a noise canceling process which is a basic process of the touch panel system 1a.
  • both the main sensor group 31a and the sub sensor group 32a output signals to the subtracting unit 41.
  • the capacity of the specific main sensor 31 corresponding to the touch position increases. That is, the output signal value from the main sensor 31 (sense line 33) increases.
  • the touch panel system 1 a outputs output signals from the sense line 33 and the sub sense line 34 to the subtracting unit 41 while driving each drive line 35.
  • noise such as a clock generated by the display device 2 and other external noise are reflected on the touch panel 3a.
  • various noise components are detected in the main sensor group 31a and the sub sensor group 32a. That is, a noise signal (noise component) is added to the original signal of the touch operation in the output signal from the main sensor group 31a.
  • the sub sensor group 32a is configured not to detect a touch operation. For this reason, the output signal from the sub sensor group 32a includes a noise signal (noise component), but does not include a touch operation signal (F501).
  • the main sensor group 31a and the sub sensor group 32a are provided in the same plane and adjacent to each other. For this reason, the noise signal value included in the output signal of the main sensor group 31a and the noise signal value that is the output signal of the sub sensor group 32a can be regarded as basically the same value. Therefore, the subtraction unit 41 present in the touch panel controller 4 executes a process of subtracting the input signal (signal value) from the sub sensor group 32a from the input signal (signal value) from the main sensor group 31a (F502). . That is, the subtracting unit 41 calculates a difference between each sense line 33 and the sub sense line 34. Thereby, the noise signal is removed from the output signal from the main sensor group 31a. Therefore, the original signal value of the touch operation generated by the touch operation can be obtained.
  • the signal thus subtracted is output to the coordinate detection unit 42 present in the touch panel controller 4 (F503).
  • the original signal for the touch operation is output to the coordinate detection unit 42.
  • the coordinate detection unit 42 detects the presence / absence of the touch operation and the touch position (coordinates) by signal processing inherent to the touch operation. Therefore, it is possible to suppress a decrease in the detection sensitivity of the coordinate detection unit 42 (detection accuracy of presence / absence of touch operation, detection sensitivity of touch position, etc.).
  • the output signal from the sense line 33 including the specific main sensor 31 corresponding to the touch position has a waveform as shown in FIG. 3A, and the sub sensor group 32a (sub sense line).
  • the output signal from 34) has a waveform as shown in FIG.
  • the subtracting unit 41 subtracts the output signal from the sub sensor group 32a from the output signal from the main sensor group 31a.
  • the noise component output from the sub sensor group 32a is removed from the output signal from the main sensor group 31a as shown in FIG. Therefore, the original signal of the touch operation generated by the touch operation can be obtained.
  • the original signal of the touch operation is input to the coordinate detection unit 42, neither the detection accuracy of the touch operation nor the detection accuracy of the touch position is lowered. For this reason, the deviation between the actual touch position and the detection position detected by the coordinate detection unit 42 can be reduced.
  • the touch panel system 1a reads the change in the capacitance value of the main sensor group 31a by the sense line 33 when the user performs a touch operation while driving the drive line 35. Further, the noise component is read by the sub sense line 34. Further, the subtracting unit 41 can take the difference between the sense line 33 and the sub-sense line 34 and remove (cancel) the noise component.
  • the main sensor group 31a includes a plurality of main sensors 31 arranged in a matrix in the vertical direction and the horizontal direction.
  • the coordinate detection part 42 can detect the touched coordinate. That is, the touch position (coordinate value) can be detected along with the presence or absence of the touch operation.
  • the noise component to be removed is not limited to the AC signal component. Therefore, the touch panel system 1a can also cancel all noises reflected on the touch panel 3a.
  • FIG. 7 is a schematic diagram showing a basic configuration of another touch panel system 1b according to the present invention.
  • the basic configuration of touch panel system 1b is substantially the same as touch panel system 1a of the second embodiment.
  • the touch panel system 1b will be described focusing on differences from the touch panel system 1a.
  • members having the same functions as those in the drawings described in the first and second embodiments are denoted by the same reference numerals and description thereof is omitted.
  • the touch panel 3b has the same configuration as the touch panel 3a of the touch panel system 1a of the second embodiment. That is, the touch panel 3b is orthogonal to the plurality of drive lines 35 (five in FIG. 7), the plurality of sense lines 33 (seven in FIG. 7) intersecting each drive line 35, and the drive lines 35. , One sub-sense line 34 parallel to the sense line 33 is provided. The sense line 33 and the drive line 35, and the sub sense line 34 and the drive line 35 are insulated from each other and capacitively coupled.
  • the eight sense / subsense sequences including one sub-sense line 34 and seven sense lines 33 will be described separately as array (1) to array (8).
  • the touch panel controller 4 includes a switch SW, a subtraction unit 41, storage units 45a to 45d, and an addition unit 46 in order from the input side. Although not shown, the touch panel controller 4 also includes a coordinate detection unit 42 and a CPU 43 (FIG. 1). Thus, the touch panel system 1b differs from the touch panel systems 1 and 1a in the configuration of the touch panel controller 4.
  • the switch SW switches a signal input from the sense line 33 or the sub-sense line 34 to the subtracting unit 41. More specifically, the switch SW has two terminals on the upper and lower sides, and one terminal is selected. FIG. 7 shows a state where the switch SW has selected the lower terminal.
  • the subtraction unit 41 performs differential signal processing on the signals of the arrays (1) to (8) selected by the switch SW. That is, the subtraction unit 41 performs difference signal processing between adjacent sense lines 33 and difference signal processing between adjacent sense lines 33 and sub-sense lines 34. For example, as shown in FIG. 7, when the lower terminal is selected by the switch SW, the subtracting unit 41 includes the array (8) -array (7), array (6) -array (5), array (4). ) -Array (3) and array (2) -array (1) differential signal processing. On the other hand, although not shown, when the upper terminal is selected by the switch SW, the subtraction unit 41 arranges the array (7) -array (6), array (5) -array (4), and array (3)- Each differential signal processing of the array (2) is performed.
  • the storage units 45a to 45d store the signals (difference processing signals) subjected to the difference processing by the subtraction unit 41 when one terminal is selected by the switch SW.
  • the difference processing signals stored in the storage units 45a to 45d are output to the addition unit 46.
  • the difference processing signal is directly output to the adding unit 46 without passing through the storage units 45a to 45d.
  • the addition unit 46 adds the difference processing signals of the adjacent sense lines 33 input from the subtraction unit 41 and the storage units 45a to 45d, and outputs the result of the addition processing. Further, the adding unit 46 outputs a difference processing signal (array (2) -array (1)) between the sub sense line 34 stored in the storage unit 45a and the adjacent sense line 33. Finally, the adding unit 46 is arranged as array (2) -array (1), array (3) -array (1), array (4) -array (1), array (5) -array (1), array (6) -Output signals of array (1), array (7) -array (1), array (8) -array (1). In other words, the signal output from the adder 46 has the noise signal (signal of array (1)) included in the sense line 33 removed. In addition, the subtracting unit 41 performs differential signal processing between adjacent sense lines 33. Therefore, a signal from which the noise signal has been removed more reliably is output from the adder 46.
  • FIG. 8 is a flowchart showing a noise cancellation process which is a basic process of the touch panel system 1b.
  • the touch panel system 1b When the touch panel system 1b is activated, a potential is applied to the drive line 35 at a constant cycle.
  • the capacity of the specific sense line 33 corresponding to the touch position increases. That is, the output signal value from the sense line 33 increases.
  • the touch panel system 1 b outputs output signals from the sense line 33 and the sub sense line 34 to the touch panel controller 4 while driving each drive line 35.
  • the touch panel system 1b detects the capacitance change of the sense line 33 and the sub sense line 34 while driving the drive line 35, and detects the presence / absence of the touch operation and the touch position.
  • noise such as a clock generated by the display device 2 and other external noise are reflected on the touch panel 3b.
  • various noise components are detected in the main sensor group 31a and the sub sensor group 32a. That is, a noise signal (noise component) is added to the original signal of the touch operation in the output signal from the sense line 33.
  • the sub sense line 34 does not detect a touch operation. For this reason, the output signal from the sub sense line 34 includes a noise signal (noise component), but does not include a touch operation signal (F601).
  • the lower terminal is selected (F602). Then, in the subtracting unit 41, between the sense line 33 (sense line Sn) and the sense line (sense line Sn + 1) closer to the sub sense line 34 out of two sense lines 33 adjacent to a certain sense line 33. (Sense line (Sn + 1) -Sn: first difference). At this time, for the sense line 33 closest to the sub sense line 34, a difference (third difference) from the sub sense line 34 is taken (F603).
  • the difference values A, C, E, and G calculated by the subtraction unit 41 are stored in the storage units 45a to 45d. That is, the storage unit 45a stores the difference value A, the storage unit 45b stores the difference value C, the storage unit 45c stores the difference value E, and the storage unit 45d stores the difference value G (F604).
  • the switch SW in which the lower terminal is selected is switched so as to select (close) the upper terminal (F605).
  • the subtraction unit 41 performs the same process as F603. That is, the difference signal between the sense line 33 (sense line Sn) and the sense line (sense line Sn-1) farther from the sub sense line 34 out of the two sense lines 33 adjacent to a certain sense line 33. Processing (sense line Sn- (Sn-1)): second difference) is performed. (F606).
  • the addition unit 46 performs addition processing of the difference values B, D, and F obtained in step F606 and the difference values A, C, E, and G stored in the storage units 45a to 45d. That is, the difference value (difference values A, C, E, G) when the lower terminal is selected by the switch SW and the difference value (difference values B, D, F) when the upper terminal is selected. Are added (F607).
  • the adding unit 46 first outputs the difference value A (array (2) -array (1) signal) stored in the storage unit 45a and the subtracting unit 41.
  • the difference value B array (3) -array (2) signal
  • the array (3) -array (1) signal can be acquired.
  • the adding unit 46 sequentially proceeds with such processing.
  • the difference value C (array (4) -array (3) signal) stored in the storage unit 45b is added to the difference value H (array (3) -array (1) signal).
  • an array (4) -array (1) signal (difference value I) can be acquired.
  • the difference value D (array (5) -array (4) signal) output from the subtractor 41 is added to the difference value I (array (4) -array (1) signal).
  • the array (5) -array (1) signal (difference value J) can be acquired.
  • the difference value E (array (6) -array (5) signal) stored in the storage unit 45c is added to the difference value J (array (5) -array (1) signal).
  • the array (6) -array (1) signal (difference value K) can be acquired.
  • the difference value F (array (7) -array (6) signal) output from the subtracting unit 41 is added to the difference value K (array (6) -array (1) signal).
  • an array (7) -array (1) signal (difference value L) can be acquired.
  • the difference value G (array (8) -array (7) signal) stored in the storage unit 45d is added to the difference value L (array (7) -array (1) signal).
  • the array (8) -array (1) signal (difference value M) can be acquired.
  • the difference value A (that is, the array (2) -array (1) signal) stored in the storage unit 45a is output without being added by the adding unit 46.
  • array (2) to array (8) are sense lines 33, and array (1) is a sub-sense line 34.
  • the signals (noise signals) in the array (1) are removed from the signals in the arrays (2) to (8). Therefore, the output signal from the adder 46 is obtained by removing the noise signal included in the signal of the sense line 33, and the original signal value of the touch operation generated by the touch operation can be obtained.
  • the output signal of the adder 46 from which the noise signal has been removed is output to the coordinate detector 42 in the touch panel controller 4. That is, the original signal of the touch operation is output to the coordinate detection unit 42 (F608).
  • the touch panel system 1b acquires the difference signal value between the adjacent sense lines 33. That is, a difference between adjacent sense lines 33 having higher noise correlation is obtained. Further, the signal (noise signal) of the sub sense line 34 is also removed from the output signal of each sense line 33. Accordingly, the touch panel system 1b can more reliably remove noise than the touch panel systems 1 and 1a of the first and second embodiments.
  • the addition process of the addition unit 46 is performed in order from the sub-sense line 34 side (in the order of the distance from the sub-sense line 34), so that the addition process proceeds while the addition process result is used for the next addition process. , Noise can be removed.
  • the driving method of the touch panel system of the present invention is not particularly limited, but is preferably an orthogonal series driving method. In other words, it is preferable to drive the drive lines 35 in parallel.
  • FIG. 9 is a diagram illustrating a touch panel driving method in a conventional touch panel system.
  • FIG. 10 is a diagram showing a touch panel drive method (orthogonal series drive method) in the touch panel system of the present invention.
  • FIG. 9 shows a case where there are four sensors in one sense line extracted from the touch panel.
  • + V volts are applied to the drive line to be driven, and the drive line is sequentially driven.
  • the fourth drive line drive applies + V volts to the rightmost sensor.
  • FIG. 10 also shows the case where there are four sensors in one sense line extracted from the touch panel, as in FIG.
  • + V volts or -V volts are applied to all the drive lines when driving the drive lines. That is, in the orthogonal sequence driving method, the drive lines are driven in parallel.
  • the first drive line drive applies + V volts to all sensors.
  • the values of the capacitance values can be obtained by the inner product calculation of the output series (Y1, Y2, Y3, Y4) and the orthogonal code di.
  • This formula holds because of the orthogonality of the orthogonal code di.
  • the sign di indicates the sign of positive and negative voltages applied to each drive line. That is, the symbol d1 is a symbol of the voltage applied to the leftmost sensor, and is “+1, +1, +1, +1”.
  • a symbol d2 is a symbol of a voltage applied to the second sensor from the left, and is “+1, ⁇ 1, +1, ⁇ 1”.
  • a symbol d3 is a symbol of a voltage applied to the third sensor from the left, and is “+1, +1, ⁇ 1, ⁇ 1”.
  • the symbol d4 is the symbol of the voltage applied to the leftmost sensor and is “+1, ⁇ 1, ⁇ 1, +1”.
  • FIG. 11 is a diagram showing a process necessary for obtaining the same sensitivity as that of the driving touch panel of FIG. 10 by the driving touch panel of FIG.
  • the drive time of the drive line is four times.
  • the driving time of the drive line is 1 ⁇ 4 that of the driving method shown in FIG. Shortened to Therefore, the power consumption of the touch panel system can be reduced.
  • FIG. 12 is a schematic diagram showing a touch panel system 1c including such an orthogonal series driving touch panel 3. That is, the touch panel system 1c in FIG. 12 shows the generalized four drive lines and one sense line shown in FIG.
  • capacitances are formed in a matrix between M drive lines 35 and L sense lines 33 (M and L are natural numbers).
  • the M drive lines 35 are all simultaneously arranged in parallel so that + V volts is obtained in the case of +1, and ⁇ V volts in the case of ⁇ 1.
  • the touch panel system 1c includes a charge integrator 47 (decoding unit) in order to perform such inner product calculation.
  • the touch panel 3 is driven by the orthogonal series driving method.
  • the signal of the capacity Cij is obtained by multiplying N (code length) by calculating the inner product of the code di and the output sequence sj.
  • the effect of this driving method does not depend on the number M of drive lines 35, and the signal strength of the capacitor becomes N times.
  • the drive time of the drive line is the case of the driving method shown in FIG. 1 / N. That is, it is possible to reduce the number of times the drive line is driven. Therefore, the power consumption of the touch panel system 1c can be reduced.
  • FIG. 13 is a schematic diagram showing a basic configuration of a touch panel system 1d according to the present embodiment.
  • the touch panel system 1d is obtained by applying the orthogonal series driving method of the drive lines 35 in the touch panel system 1c shown in FIGS. 10 and 12 to the touch panel system 1b with a noise canceling function shown in FIG. Since the operation of the touch panel system 1d is the same as that of the touch panel systems 1b and 1c described above, description thereof is omitted.
  • a differential signal value is acquired between adjacent sense lines 33. That is, a difference between adjacent sense lines 33 having higher noise correlation is obtained. Further, the signal (noise signal) of the sub sense line 34 is also removed from the output signal of each sense line 33. Therefore, the touch panel system 1d can more reliably remove noise than the touch panel systems 1 and 1a of the first and second embodiments. Furthermore, since the signal of the capacitance Cij is obtained by multiplying it by N (code length), the signal strength of the capacitor becomes N times regardless of the number of drive lines 35. In order to obtain the same sensitivity as that of the conventional driving method shown in FIG.
  • the driving time of the drive line is reduced to 1 / N in the case of the driving method shown in FIG. Shortened. That is, it is possible to reduce the number of times the drive line is driven. Therefore, the power consumption of the touch panel system 1d can be reduced.
  • FIG. 14 is a schematic diagram illustrating a basic configuration of the touch panel system 1e according to the present embodiment.
  • the touch panel system 1e is different in the configuration of the subtracting unit 41.
  • the subtraction unit 41 includes an AD conversion unit 48 (third AD conversion unit) and a digital subtracter (not shown).
  • the output signal (analog signal) from the touch panel 3b is converted into a digital signal by the AD conversion unit 48 of the subtraction unit 41.
  • the digital subtractor performs a subtraction process using the converted digital signal in the same manner as the touch panel system 1b of FIG.
  • the touch panel system 1e can remove noise by performing a subtraction process after converting the analog signal output from the touch panel 3b into a digital signal.
  • FIG. 15 is a schematic diagram illustrating a basic configuration of a touch panel system 1f according to the present embodiment.
  • the touch panel system 1 f is different in the configuration of the subtracting unit 41.
  • the output signals from the sense line 33 and the sub sense line 34 of the touch panel 3b are analog signals. Therefore, the subtraction unit 41 includes a differential amplifier 49 and an AD conversion unit 48.
  • the differential amplifier 49 performs subtraction processing on the output signal (analog signal) from the touch panel 3b in the same manner as the touch panel system 1b in FIG.
  • the AD conversion unit 48 (fourth AD conversion unit) converts the subtracted analog signal into a digital signal.
  • the touch panel system 1f can remove noise by subtracting the analog signal output from the touch panel 3b as it is and converting it to a digital signal.
  • FIG. 16 is a schematic diagram illustrating a basic configuration of a touch panel system 1g according to the present embodiment.
  • the touch panel system 1g is different in the configuration of the subtracting unit 41.
  • the touch panel system 1g includes a fully differential amplifier 50 instead of the differential amplifier 49 in the touch panel system 1f of FIG.
  • the output signals from the sense line 33 and the sub sense line 34 of the touch panel 3b are analog signals. Therefore, the subtraction unit 41 includes a fully differential amplifier 50 and an AD conversion unit 48.
  • the fully differential amplifier 50 performs a subtraction process on the output signal (analog signal) from the touch panel 3b in the same manner as the touch panel system 1b in FIG.
  • the AD converter 48 converts the subtracted analog signal into a digital signal.
  • FIG. 17 is a circuit diagram showing an example of the fully differential amplifier 50.
  • the fully differential amplifier 50 two pairs of capacitances and switches are arranged symmetrically to the differential amplifier. Specifically, signals from the adjacent sense line 33 are input to the non-inverting input terminal (+) and the inverting input terminal ( ⁇ ). The same capacitance (between the inverting output terminal ( ⁇ ) and the non-inverting input terminal (+) of the differential amplifier and between the non-inverting output terminal (+) and the inverting input terminal ( ⁇ ) of the differential amplifier. Feedback capacity) is connected. Further, switches are connected between the inverting output terminal ( ⁇ ) and the non-inverting input terminal (+), and between the non-inverting output terminal (+) and the inverting input terminal ( ⁇ ), respectively.
  • the touch panel system 1g can remove noise by subtracting the analog signal output from the touch panel 3b as it is and converting it to a digital signal.
  • FIG. 18 is a schematic diagram showing a basic configuration of a touch panel system 1h according to the present embodiment.
  • the touch panel system 1h differs in the structure of the subtraction part 41 and the drive system of the touch panel 3b.
  • the touch panel system 1h includes a fully differential amplifier 50 instead of the differential amplifier 49 in the touch panel system 1f of FIG.
  • the output signals from the sense line 33 and the sub sense line 34 of the touch panel 3b are analog signals. Therefore, the subtraction unit 41 includes a fully differential amplifier 50 and an AD conversion unit 48.
  • the fully differential amplifier 50 performs a subtraction process on the output signal (analog signal) from the touch panel 3b in the same manner as the touch panel system 1b in FIG.
  • the AD converter 48 converts the subtracted analog signal into a digital signal.
  • the orthogonal series driving method shown in FIGS. 10, 12, and 13 is applied as the driving method of the touch panel 3b.
  • the voltage for driving the four drive lines is the first time in the second to fourth times, while the + V application and the -V application are the same two times.
  • + V is applied four times. Therefore, the output value of the first output series Y1 is larger than the output values of the second to fourth output series Y2 to Y4. For this reason, if the dynamic range is adjusted to the output values of the second to fourth output series Y2 to Y4, the first output series Y1 will be saturated.
  • the subtraction unit 41 of the touch panel system 1h includes a fully differential amplifier 50.
  • the fully differential amplifier 50 employs an input common mode voltage range that operates in a rail-to-rail manner. That is, the fully differential amplifier 50 has a wide common mode input range.
  • the fully differential amplifier 50 can operate in a voltage range from the power supply voltage (Vdd) to GND. Further, the difference between the input signals to the fully differential amplifier 50 is amplified. Therefore, no matter what the orthogonal series driving type touch panel 3b is combined, the problem of output saturation does not occur in the output signal from the fully differential amplifier 50.
  • An example of the fully differential amplifier 50 is as shown in FIG.
  • the touch panel system 1h can remove noise by subtracting the analog signal output from the touch panel 3b as it is and converting it to a digital signal. Further, since the fully differential amplifier 50 capable of rail-to-rail operation is provided, the output signal from the fully differential amplifier 50 does not cause a problem of output saturation.
  • the touch panel system including the sub sensor 32 (sub sense line 34) has been described.
  • the sub sensor 32 is not an essential configuration.
  • a touch panel panel system that does not include the sub sensor 32 will be described.
  • FIG. 20 is a schematic diagram showing a basic configuration of the touch panel system 1i according to the present embodiment.
  • the touch panel system 1 i includes a subtracting unit 41 a that calculates a difference signal between adjacent sense lines 33.
  • the touch panel 3c includes a plurality (five in FIG. 20) of drive lines 35 and a plurality (eight in FIG. 20) of sense lines 33 intersecting each drive line 35. .
  • the sense line 33 and the drive line 35 are insulated from each other and capacitively coupled.
  • the touch panel controller 4 includes a switch SW, a subtraction unit 41a, and storage units 45a to 45d in order from the input side. Although not shown, the touch panel controller 4 also includes a coordinate detection unit 42 and a CPU 43 (see FIG. 1).
  • the subtractor 41a includes an input terminal (input terminal for main sensor output) for receiving a signal output from the main sensor 31.
  • the subtractor 41a receives a signal from the main sensor 31, subtracts the signals of the adjacent sense lines 33, and calculates a difference value (difference signal).
  • the signal subjected to the subtraction processing by the subtraction unit 41a is output to the coordinate detection unit 42 (see FIG. 1).
  • the touch panel system 1i is different from the touch panel system of the above-described embodiment in that the sub sensor 32 (sub sense line 34) is not provided and the processing of the subtraction unit 41a is not performed.
  • the switch SW switches a signal input from the sense line 33 to the subtraction unit 41a. More specifically, the switch SW has two terminals on the upper and lower sides, and one terminal is selected. FIG. 20 shows a state where the switch SW has selected the lower terminal.
  • the subtraction unit 41a performs differential signal processing of the signals of the arrays (1) to (8) selected by the switch SW. That is, the subtraction unit 41a performs differential signal processing between adjacent sense lines 33. For example, as shown in FIG. 20, when the lower terminal is selected by the switch SW, the subtracting unit 41a includes the array (8) -array (7), the array (6) -array (5), and the array (4). ) -Array (3) and array 2) -array (1) differential signal processing is performed. On the other hand, although not shown, when the upper terminal is selected by the switch SW, the subtracting unit 41a performs the arrangement (7) -array (6), array (5) -array (4), and array (3)- Each differential signal processing of the array (2) is performed.
  • the storage units 45a to 45d store a signal (difference processing signal) subjected to difference processing by the subtraction unit 41a when one terminal is selected by the switch SW. When the other terminal is selected by the switch SW, the difference processing signal is directly output without passing through the storage units 45a to 45d.
  • FIG. 21 is a flowchart showing a noise canceling process which is a basic process of the touch panel system 1i.
  • the touch panel system 1i When the touch panel system 1i is activated, a potential is applied to the drive line 35 at a constant cycle.
  • the capacitance of the specific sense line 33 corresponding to the touch position changes. That is, the output signal value from the sense line 33 changes.
  • the touch panel system 1 i outputs an output signal from the sense line 33 to the touch panel controller 4 while driving each drive line 35.
  • the touch panel system 1i detects the capacitance change of the sense line 33 while driving the drive line 35, and detects the presence / absence of the touch operation and the touch position.
  • noise such as a clock generated by the display device 2 and other external noise are reflected on the touch panel 3c.
  • various noise components are detected in the main sensor group 31b. That is, the noise signal (noise component) is added to the original signal of the touch operation in the output signal from the sense line 33 (F701).
  • the lower terminal of the switch SW is selected (F702).
  • the subtracting unit 41a a difference between the sense line 33 (sense line Sn) and one of the two sense lines 33 adjacent to the sense line 33 (sense line Sn + 1) is obtained (sense).
  • the difference values A, C, E, and G calculated by the subtraction unit 41a are stored in the storage units 45a to 45d. That is, the storage unit 45a stores the difference value A, the storage unit 45b stores the difference value C, the storage unit 45c stores the difference value E, and the storage unit 45d stores the difference value G (F704).
  • the switch SW in which the lower terminal is selected is switched so as to select (close) the upper terminal (F705).
  • the subtraction unit 41a performs the same process as F703. That is, differential signal processing (sense line Sn ⁇ ) between the sense line 33 (sense line Sn) and the other sense line (sense line Sn ⁇ 1) of the two sense lines 33 adjacent to a certain sense line 33. (Sn-1)): second difference). (F706).
  • the arrays (1) to (8) in FIG. Array (3) -array (2) (this difference value is B)
  • Array (5) -array (4) (this difference value is set to D)
  • Array (7) -Array (6) (this difference value is F)
  • the three differential signal processes are performed. That is, in step F706, differential signal processing of arrays (2) to (7) is performed.
  • the touch panel system 1 i acquires a differential signal value between adjacent sense lines 33. That is, a difference between adjacent sense lines 33 having higher noise correlation is obtained. That is, the noise component is removed from the output signal of the main sensor group 31a, and the original signal of the touch operation is extracted. Therefore, various types of noise reflected on the touch panel 3c can be reliably removed (cancelled).
  • FIG. 22 is a schematic diagram showing a basic configuration of a touch panel system 1j according to the present embodiment.
  • the touch panel system 1j is obtained by applying a drive line drive circuit (not shown) for driving the drive lines 35 in parallel to the above-described touch panel system 1i with a noise cancellation function shown in FIG. Further, the touch panel system 1j stores a decoding unit 58 for decoding the capacitance difference value calculated by the subtraction unit 41a, and a capacitance difference distribution decoded by the decoding unit 58 during a non-touch operation.
  • a non-touch operation information storage unit 61, and a calibration unit 62 that calibrates the difference distribution of the capacitance decrypted by the decryption unit 58 during the touch operation.
  • N 2 n ⁇ 1
  • Such a series has the property that the following expression holds.
  • the decoding unit 58 decodes the difference value of the capacitance calculated by the subtraction unit 41a (that is, the difference distribution of the capacitance value in the direction of the sense line 33). Specifically, the inner product of the code series for driving the drive lines 33 in parallel and the difference distribution of the capacitance values in the sense line 33 direction is calculated. Therefore, the inner product value after decoding by the decoding unit 58 is expressed by the following equation.
  • the decoding unit 58 calculates the difference distribution ( ⁇ sC) kj, P of the capacitance value in the direction of the sense line 33 as N as the principal component of the inner product values d i s j, P after decoding. . Therefore, by making the inner product value d i ⁇ s j, P as an estimated value of the capacitance value difference distribution ( ⁇ sC) ij, P in the sense line 33 direction, the signal intensity of the capacitance value is multiplied by N (code length). Can be read.
  • the touch panel 3c is driven in parallel, and the decoding unit 58 decodes the difference value of the capacitance calculated by the subtraction unit 41a.
  • the capacitance signal is obtained by multiplying the code length (N times)
  • the signal strength of the capacitance increases without depending on the number of drive lines 35.
  • the driving time of the drive line 35 is shortened to 1 / N in the case of the driving method shown in FIG. That is, the number of times of driving the drive line 35 can be reduced. Therefore, the power consumption of the touch panel system 1j can be reduced.
  • the calibration unit 62 the estimated value of the difference distribution ( ⁇ sC) kj when a touch operation is, difference distribution during non-touch operation stored in the non-touch operation when the information storage unit 61 ( ⁇ sC) kj, the P Subtract the estimated value.
  • the calibration unit 62 subtracts the capacitance difference distribution during the non-touch operation stored in the non-touch operation information storage unit 61 from the capacitance difference distribution during the touch operation (touch operation). Difference value signal at time-difference value signal at non-touch operation). Therefore, the offset inherent in the touch panel 3c can be canceled.
  • the difference component due to the capacity variation inherent in the touch panel 3c is eliminated, and only the difference component due to the touch operation is detected.
  • FIG. 23 is a schematic diagram showing a basic configuration of a touch panel system 1k according to the present embodiment.
  • the touch panel system 1k is different in the configuration of the subtraction unit 41a.
  • the output signal from the sense line 33 of the touch panel 3c is an analog signal. Therefore, the subtraction unit 41a includes an AD conversion unit 48a (first AD conversion unit) and a digital subtracter (not shown).
  • the output signal (analog signal) from the touch panel 3c is converted into a digital signal by the AD conversion unit 48a of the subtraction unit 41a.
  • the digital subtracter performs a subtraction process using the converted digital signal in the same manner as the touch panel systems 1i and 1j in FIG.
  • the touch panel system 1k can remove noise by performing a subtraction process after converting the analog signal output from the touch panel 3c into a digital signal.
  • FIG. 24 is a schematic diagram illustrating a basic configuration of a touch panel system 1m according to the present embodiment.
  • the touch panel system 1m is different in the configuration of the subtraction unit 41a.
  • the output signal from the sense line 33 of the touch panel 3c is an analog signal. Therefore, the subtraction unit 41a includes a differential amplifier 49 and an AD conversion unit 48a (second AD conversion unit).
  • the differential amplifier 49 performs subtraction processing on the output signal (analog signal) from the touch panel 3c in the same manner as the touch panel system 1i of FIG.
  • the AD converter 48a converts the subtracted analog signal into a digital signal.
  • the touch panel system 1m can remove the noise by subtracting the analog signal output from the touch panel 3c as it is and converting it to a digital signal.
  • FIG. 25 is a schematic diagram showing a basic configuration of a touch panel system 1n according to the present embodiment.
  • the touch panel system 1n is different in the configuration of the subtraction unit 41a.
  • the touch panel system 1n includes a fully differential amplifier 50 instead of the differential amplifier 49 in the touch panel system 1m of FIG.
  • the output signal from the sense line 33 of the touch panel 3c is an analog signal. Therefore, the subtraction unit 41a includes a fully differential amplifier 50 and an AD conversion unit 48a.
  • the fully differential amplifier 50 performs a subtraction process on the output signal (analog signal) from the touch panel 3c in the same manner as the touch panel system 1i of FIG.
  • the AD converter 48a converts the subtracted analog signal into a digital signal.
  • the touch panel system 1n can subtract the analog signal output from the touch panel 3c as it is and convert it to a digital signal to remove noise.
  • FIG. 26 is a schematic diagram illustrating a basic configuration of the touch panel system 1o according to the present embodiment.
  • the touch panel system 1o is different in the configuration of the subtraction unit 41a.
  • the touch panel system 1o includes a fully differential amplifier 50 instead of the differential amplifier 49 in the touch panel system 1m of FIG.
  • the output signal from the sense line 33 of the touch panel 3c is an analog signal. Therefore, the subtraction unit 41a includes a fully differential amplifier 50 and an AD conversion unit 48a.
  • the fully differential amplifier 50 performs a subtraction process on the output signal (analog signal) from the touch panel 3c in the same manner as the touch panel system 1i of FIG.
  • the AD converter 48a converts the subtracted analog signal into a digital signal.
  • the orthogonal series driving method shown in FIGS. 10, 12, and 22 is applied as the driving method of the touch panel 3c.
  • the voltage for driving the four drive lines is the first time in the second to fourth times, while the + V application and the -V application are the same two times.
  • + V is applied four times. Therefore, the output value of the first output series Y1 is larger than the output values of the second to fourth output series Y2 to Y4. For this reason, if the dynamic range is adjusted to the output values of the second to fourth output series Y2 to Y4, the first output series Y1 will be saturated.
  • the subtracting unit 41a of the touch panel system 1o includes a fully differential amplifier 50.
  • the fully differential amplifier 50 employs an input common mode voltage range that operates in a rail-to-rail manner. That is, the fully differential amplifier 50 has a wide common mode input range. As a result, the fully differential amplifier 50 can operate in a voltage range from the power supply voltage (Vdd) to GND. Further, the difference between the input signals to the fully differential amplifier 50 is amplified. Therefore, no matter what the orthogonal series drive type touch panel 3c is combined, the problem of output saturation does not occur in the output signal from the fully differential amplifier 50.
  • An example of the fully differential amplifier 50 is as shown in FIG.
  • the touch panel system 1o can remove the noise by subtracting the analog signal output from the touch panel 3c as it is and converting it to a digital signal. Further, since the fully differential amplifier 50 capable of rail-to-rail operation is provided, the output signal from the fully differential amplifier 50 does not cause a problem of output saturation.
  • the touch panel system 1j determines whether or not there is a touch operation based on a comparison between the difference between the signals of the adjacent sense lines 33 calculated by the subtraction unit 41a and the decoding unit 58 and a positive and negative threshold. (Touch detection unit).
  • the determination unit 59 receives a signal that has been calibrated by the calibration unit 62 (capacitance difference distribution) or a signal that has not been calibrated by the calibration unit 62 (capacitance difference distribution). .
  • the capacitance difference distribution decoded by the decoding unit 58 is directly input to the determination unit 59.
  • the case where the signal which is not calibrated by the calibration part 62 is input into the determination part 59 is demonstrated. However, the same applies to the case where the calibration-processed signal is input to the determination unit 59.
  • FIG. 27 is a flowchart showing the basic processing of the determination unit 59 in the touch panel system 1j of FIG.
  • FIG. 28 is a schematic diagram illustrating a touch information recognition method in the flowchart of FIG.
  • the determination unit 59 first obtains a difference value (difference distribution) “( ⁇ sC) ij, P ” between signals of adjacent sense lines calculated by the subtraction unit 41a and the decoding unit 59. (F801). Next, the difference value is compared with the positive threshold value THp and the negative threshold value THm stored in the determination unit 59, and an increase / decrease table is created (F802).
  • This increase / decrease table is, for example, a ternary increase / decrease table as shown in FIG.
  • the ternary increase / decrease table is converted (binarized) into a binary image (F803).
  • F803 binary image
  • the increase / decrease table in FIG. 28A when scanning in the order of the sense line S1 to sense line S7 (toward the right in the figure), if “+” appears in the increase / decrease table, all are followed until the next “ ⁇ ” appears. If “1” or “ ⁇ ” appears, all of them are converted back to “1” by going back in the scanning direction (leftward in the figure). Thereby, binarized data as shown in FIG. 28B is obtained.
  • a connected component is extracted (F804).
  • a connected component is extracted (F804).
  • FIG. 28B when “1” overlaps the same sense line position on adjacent drive lines, they are regarded as the same connected component and are determined as touch position candidates. That is, in FIG. 28C, “1” surrounded by a frame is regarded as the same connected component, and is extracted as a touch position candidate.
  • touch information touch size, touch position, etc. is recognized based on the extracted touch position candidates (F805).
  • the determination unit 59 determines the presence or absence of the touch operation based on the difference between the signals of the adjacent sense lines 33 from which the noise signal has been removed. Therefore, the presence / absence of a touch operation can be accurately determined.
  • the determination unit 59 determines each sense based on the comparison between the difference between the signals of the adjacent sense lines 33 calculated by the subtraction unit 41a and the positive and negative threshold values (THp, THm).
  • An increase / decrease table in which the difference distribution of the signal of the line 33 is ternarized is created, and the increase / decrease table is converted into a binary image. That is, the difference between the signals of the adjacent sense lines from which the noise signal has been removed is input to the determination unit 59.
  • the determination unit 59 uses the difference between the signals of the adjacent sense lines 33 and the comparison between the positive and negative threshold values (THp, THm) stored in the determination unit 59 to determine the difference between the signals of the sense lines 33.
  • An increase / decrease table in which the distribution is ternarized is created. Further, the determination unit 59 converts the increase / decrease table into a binary image by binarizing the increase / decrease table. Thereby, touch position candidates are extracted from the converted binary image. Therefore, by recognizing touch information (touch size, position, etc.) based on this binary image, it is possible to more accurately recognize touch information in addition to the presence or absence of a touch operation.
  • FIG. 29 is a functional block diagram showing the configuration of the mobile phone 10 equipped with the touch panel system 1.
  • the cellular phone (electronic device) 10 includes a CPU 51, a RAM 53, a ROM 52, a camera 54, a microphone 55, a speaker 56, operation keys 57, and the touch panel system 1. Each component is connected to each other by a data bus.
  • the CPU 51 controls the operation of the mobile phone 10.
  • the CPU 51 executes a program stored in the ROM 52, for example.
  • the operation key 57 receives an instruction input by the user of the mobile phone 10.
  • the RAM 53 stores data generated by the execution of the program by the CPU 51 or data input via the operation keys 57 in a volatile manner.
  • the ROM 52 stores data in a nonvolatile manner.
  • the ROM 52 is a ROM capable of writing and erasing, such as an EPROM (Erasable Programmable Read-Only Memory) and a flash memory.
  • EPROM Erasable Programmable Read-Only Memory
  • flash memory a flash memory
  • the mobile phone 10 may be configured to include an interface (IF) for connecting to another electronic device by wire.
  • IF interface
  • the camera 54 shoots a subject in accordance with the operation of the user operation key 57.
  • the image data of the photographed subject is stored in the RAM 53 or an external memory (for example, a memory card).
  • the microphone 55 receives user's voice input.
  • the mobile phone 10 digitizes the input voice (analog data). Then, the mobile phone 10 sends the digitized voice to a communication partner (for example, another mobile phone).
  • the speaker 56 outputs sound based on music data stored in the RAM 53, for example.
  • the touch panel system 1 includes a touch panel 3, a touch panel controller 4, a drive line drive circuit 5, and a display device 2.
  • the CPU 51 controls the operation of the touch panel system 1.
  • the CPU 51 executes a program stored in the ROM 52.
  • the RAM 53 stores data generated by the execution of the program by the CPU 51 in a volatile manner.
  • the ROM 52 stores data in a nonvolatile manner.
  • Display device 2 displays images stored in ROM 52 and RAM 53.
  • the display device 2 is superimposed on the touch panel 3 or contains the touch panel 3.
  • a touch panel system including a touch panel having a plurality of sensors and a touch panel controller that inputs signals from the sensors and reads data, the touch panel inputs a signal by a user performing a touch operation.
  • a touch panel system comprising: subtracting means for subtracting a signal from the sub sensor.
  • a touch panel arranged at the top of the display screen of the display device, and a plurality of sensor groups arranged in a matrix, and a touch panel controller that inputs signals from the sensor groups and reads data
  • the touch panel includes a main sensor group that inputs a signal when a user performs a touch operation, and a sub sensor group installed on the same touch panel as the main sensor group.
  • a touch panel having subtracting means for receiving a signal from the main sensor group and a signal from the sub sensor group and subtracting a signal from the sub sensor group from the signal from the main sensor group. system.
  • the touch panel includes a main sensor unit that detects a touch operation and a sub-sensor unit for noise detection, and the subtracting unit takes a signal difference between the main sensor unit and the sub-sensor unit. .
  • the noise signal is removed from the output signal from the main sensor unit, and the original signal of the touch operation generated by the touch operation is extracted. Therefore, various types of noise reflected on the touch panel can be reliably removed (cancelled). Therefore, the noise component to be removed is not limited to the AC signal component in the signal including noise, but is all noise components reflected on the touch panel. That is, it is possible to provide a touch panel system and an electronic device that can basically cancel all noise components.
  • FIG. 30 is a schematic diagram showing a basic configuration of another touch panel system 1r according to the present invention.
  • the basic configuration of the touch panel system 1r is substantially the same as the touch panel systems 1, 1a to 1o according to the first feature.
  • the touch panel system 1r according to the second feature will be described focusing on differences from the touch panel systems 1, 1a to 1o according to the first feature.
  • members having the same functions as those of the touch panel system 1, 1a to 1o according to the first feature are denoted by the same reference numerals, and description thereof is omitted.
  • the touch panel system 1r includes a display device 2, a touch panel 3, a touch panel controller 4, a drive line drive circuit 5, and touch information generated by the touch panel controller 4 (touch size, touch position, etc.). ) To set an effective area on the touch panel 3 and generate effective area information.
  • the drive line driving circuit 5 acquires the effective area information and grasps the effective area set by the area setting unit 8.
  • the drive line driving circuit 5 drives each drive line 35 based on the effective area set by the area setting unit 8. A specific example of a method for driving the drive line 35 by the drive line drive circuit 5 will be described later.
  • the touch panel controller 4 includes an amplifying unit 71 (for example, the differential amplifying unit 49 or the fully differential amplifying unit 50 described in the first feature) that amplifies the signal of the sense line 33, and an amplifying unit 71.
  • a signal acquisition unit 72 that acquires the amplified signal and outputs it in a time division manner, and an AD conversion unit 73 that converts the analog signal output from the signal acquisition unit 72 into a digital signal (for example, the AD conversion unit described in the first feature) 48, 48a), a decoding unit 58 that obtains a difference distribution in capacitance based on the digital signal converted by the AD conversion unit 73, and a difference distribution in capacitance obtained by the decoding unit 58.
  • a coordinate detector 42 for generating touch information.
  • Each of the amplification unit 71 and the signal acquisition unit 72 acquires the effective region information and grasps the effective region set by the region setting unit 8.
  • the amplifying unit 71 amplifies the signal of the sense line 33 based on the effective region set by the region setting unit 8.
  • the signal acquisition unit 72 selects the signal of the sense line 33 amplified by the amplification unit 71 based on the effective region set by the region setting unit 8 and outputs it in a time division manner.
  • a specific example of a signal amplification method and an acquisition method by the amplification unit 71 and the signal acquisition unit 72 will be described later.
  • the AD conversion unit 73 converts the analog signal output from the signal acquisition unit 72 into a digital signal having a predetermined number of bits.
  • the number of bits of the digital signal generated by the AD conversion unit 73 may be any number, but considering the processing accuracy (touch position detection accuracy) in the subsequent decoding unit 58 and the coordinate detection unit 42, For example, 12 bits or more and 16 bits or less are preferable.
  • the area setting unit 8 stores an effective area calculation unit 81 that sets an effective area on the touch panel 3 based on touch information and generates effective area position information, parameters necessary for the calculation of the effective area calculation unit 81, and the like.
  • a storage unit 82 stores an effective area calculation unit 81 that sets an effective area on the touch panel 3 based on touch information and generates effective area position information, parameters necessary for the calculation of the effective area calculation unit 81, and the like.
  • the effective area calculation unit 81 includes, for example, a CPU (for example, can correspond to the CPU 43 described above), acquires touch information, and grasps a touch position on the touch panel 3 calculated by the touch panel controller 4.
  • the effective area calculation unit 81 sets an effective area in the touch panel 3 based on the touch position on the touch panel 3 calculated by the touch panel controller 4 and generates effective area information.
  • the storage unit 82 includes a register 821 that stores parameters and the like necessary for the calculation of the effective area calculation unit 81. A specific example of calculation contents (effective area setting method) in the effective area calculation unit 81 will be described later.
  • FIG. 30 is a block diagram illustrating an example of an effective area.
  • the effective area A illustrated in FIG. 31 is set in a partial area of the touch panel 3.
  • Each of the drive line 35r and the sense line 33r passes through the effective area A.
  • at least a part of the capacitance formed by the drive line 35r and the sense line 33r is included in the effective area A.
  • the drive line drive circuit 5 applies a drive signal to each of the drive lines 35r passing through the effective area A.
  • the drive line drive circuit 5 does not apply a drive signal to each drive line that does not pass through the effective area A.
  • FIG. 32 is a diagram showing an example of a specific drive method of the drive line by the drive line drive circuit in the first operation example.
  • 32A shows a case where the entire surface of the touch panel 3 is set as an effective area
  • FIG. 32B shows a case where the effective area is set in a part of the touch panel 3 (FIG. 31).
  • the drive line drive circuit 5 when the entire surface of the touch panel 3 is set as an effective area, the drive line drive circuit 5 applies drive signals to all the drive lines 35. As shown in FIG. For example, the drive line drive circuit 5 applies a unique drive signal set for each drive line DL.
  • the drive signal consists of a combination of a high level (“1”) and a low level (“0”), and the signal level changes in the time direction.
  • the drive signal may be the code sequence described in the first feature.
  • the low level of the drive signal may be “ ⁇ 1”.
  • the drive line drive circuit 5 when the effective area A is set in a part of the touch panel 3, the drive line drive circuit 5 sends a drive signal to the drive line 35 r passing through the effective area A. Apply. At this time, the drive line drive circuit 5 applies the unique drive signal described above to the drive line 35r. In addition, the drive line drive circuit 5 suppresses changes in the signal level of the drive line over time by grounding each drive line that does not pass through the effective area A, for example.
  • the drive signal applied to the drive line 35r passing through the effective area A is the same as the drive signal applied to the drive line 35r in the case shown in FIG. Become a thing. Further, in the example shown in FIG. 32B, the signal level of the drive line that does not pass through the effective area A becomes a value “0” that is invariant with respect to the time direction.
  • the signal level of the drive line that does not pass through the effective area A is not limited to “0” as long as it does not change with respect to the time direction, and may be “1” or “1” and “0”. ”(For example, one of two adjacent drive lines is“ 0 ”and the other is“ 1 ”).
  • the drive line driving circuit 5 selectively drives the drive line 35r passing through the effective area A, it is possible to prevent the drive line 35 from being driven unnecessarily. For this reason, it is possible to reduce the power consumption for driving the drive line 35 and to suppress the generation of noise and improve the detection sensitivity of the touch operation. Further, the drive position 35r is driven in a limited manner, so that the touch position detection accuracy in the touch panel controller 4 can be improved.
  • the drive line drive circuit 5 controls the drive line 35 as shown in FIG. 32, so that the touch panel controller 4 (particularly the decoding unit 58) can easily change the signal of the sense line 33 caused by the touch operation. Can be identified.
  • FIG. 33 is a block diagram illustrating an example of a specific operation of the amplifying unit in the first operation example.
  • the amplifying unit 71 includes an amplifier 711 corresponding to each of the sense lines 33, and an open / close switch 712 for controlling whether or not the signal of the sense line 33 is supplied to the amplifier 711. However, each open / close switch 712 is controlled according to the valid area information.
  • the open / close switch 712 to which the signal of the sense line 33r passing through the effective area A is supplied becomes conductive.
  • the signal of the sense line 33 r passing through the effective area A is amplified by the amplifier 711 and output from the amplifier 71.
  • the open / close switch 712 to which the signal of the sense line that does not pass through the effective area A is supplied is turned off.
  • the signal on the sense line that does not pass through the effective area A is not amplified by the amplifier 711 and is not output from the amplifying unit 71.
  • the amplifying unit 71 selectively amplifies the signal of the sense line 33r passing through the effective region A, so that it is possible to reduce power consumption required for the signal amplification.
  • the structure for selectively amplifying the signal of the sense line 33r is not limited to the exemplified amplifier 711 and open / close switch 712, and may be another structure as long as the same effect can be obtained. May be.
  • a switch capable of switching between active / inactive of the amplifier 711 may be provided instead of the opening / closing switch 712 (or in addition).
  • FIG. 34 is a block diagram illustrating an example of a specific operation of the selection acquisition unit in the first operation example.
  • the signal acquisition unit 72 includes a branch switch 721 that selects one of the terminals corresponding to each of the sense lines 33 and connects it to the subsequent stage.
  • the branch switch 721 is controlled according to the valid area information.
  • the branch switch 721 can be connected to a terminal corresponding to the sense line 33r passing through the effective area A. Thereby, the signal of the sense line 33r passing through the effective area A amplified by the amplification unit 71 is output to the subsequent stage.
  • the branch switch 721 is not connected to a terminal corresponding to a sense line that does not pass through the effective area A. As a result, the signal of the sense line that does not pass through the effective area A is not output to the subsequent stage.
  • the signal acquisition unit 72 selectively acquires the signal of the sense line 33r passing through the effective region A and outputs the signal in a time division manner, so that an unnecessary signal is output to the subsequent stage of the signal acquisition unit 72. Can be prevented. Therefore, it is possible to reduce the power consumption required for the processing of the subsequent stage of the signal acquisition unit 72 (for example, the AD conversion unit 73, the decoding unit 58, and the coordinate detection unit 42).
  • the structure for selectively acquiring signals and outputting them in a time-sharing manner is not limited to the illustrated branch switch 721, and may be other structures as long as the same effect can be obtained. Also good.
  • the AD conversion unit 73 converts the analog signal output from the signal acquisition unit 72 into a digital signal
  • the decoding unit 58 calculates the difference distribution of the capacitance of the touch panel 3 (effective area A) based on the digital signal.
  • the coordinate detection unit 42 obtains the touch information by detecting the touch position of the touch panel 3 (effective area A) by referring to the difference distribution.
  • the touch panel controller 4 selectively processes the signal of the sense line 33r passing through the effective area A. Therefore, useless signal processing can be prevented. Therefore, it is possible to reduce power consumption for signal processing. Further, by processing the signal of the sense line 33r passing through the effective area A in a limited manner, the touch position detection accuracy can be improved.
  • the touch panel controller 4 performs an operation based on the effective area A set by the area setting unit 8.
  • the area setting unit 8 updates the effective area A set on the touch panel 3 based on the touch position detected by the touch panel controller 4 and sets a new effective area.
  • FIG. 35 is a flowchart illustrating an example of a specific operation of the region setting unit in the first operation example.
  • FIG. 36 is a diagram illustrating an example of an effective area setting method in the first operation example.
  • the position of the sense line 33 in the alignment direction is X
  • the alignment direction of the drive line 35 horizontal direction in the figure, Y direction
  • the position in the touch panel 3 is expressed by the coordinates (X, Y), where Y is the position.
  • the coordinates of the upper left corner of the touch panel 3 are (0, 0), and the coordinates of the lower right corner are (n, m).
  • n and m are natural numbers in which at least one is 2 or more
  • n sense lines 33 and m drive lines 35 are provided on the touch panel 3.
  • the coordinates of the upper left corner of the effective area A are (Xs, Ys)
  • the coordinates of the lower right corner of the effective area A are (Xe, Ye).
  • FIG. 36 illustrates the case where the effective area A is set with the length in the X direction as WD_S and the length in the Y direction as WD_D with the touch position (Xp, Yp) as the center. Details of the method for setting the effective area A will be described later.
  • the effective area calculation unit 81 acquires touch information generated by the touch panel controller 4 (step # 3). At this time, the effective area calculation unit 81 checks a parameter stored in the register 821 of the storage unit 82 to set a new effective area based on the touch position, “spot driving mode” (first mode) Or the “entire surface detection mode” (second mode) in which the entire surface of the touch panel 3 is continuously set as a new effective area (step # 4).
  • “Spot driving mode” and “entire surface detection mode” can be switched by, for example, a user instruction (operation). Therefore, for example, according to the installation environment or use environment of the touch panel system, the user can set the touch position without omission from the “spot driving mode” for reducing power consumption and improving the detection sensitivity of the touch operation.
  • the touch panel system 1r can be operated in any of the “entire surface detection mode” to be detected.
  • the touch panel system 1r may be configured to automatically select and operate these modes according to factors other than the user's instruction.
  • step # 7, YES When new touch information is output (step # 7, YES), the process returns to step # 3 to acquire the touch information. On the other hand, when new touch information is not output (step # 7, NO), the operation is terminated.
  • step # 4 the effective area calculation unit 81 performs the above-described “entire detection mode”. The same operation is performed (steps # 5 to # 7). As a result, since the effective area is set on the entire surface of the touch panel 3, the touch panel controller 4 detects the touch operation no matter which position on the touch panel 3 is next performed, It becomes possible to detect the touch position.
  • the effective area calculation unit 81 includes the touch position.
  • the effective area calculation unit 81 outputs the calculated effective area information (step # 6).
  • the effective area calculation unit 81 can set a new effective area A that is likely to include a position where the touch position is detected next.
  • step # 7, YES When new touch information is output (step # 7, YES), the process returns to step # 3 to acquire the touch information. On the other hand, when new touch information is not output (step # 7, NO), the operation is terminated.
  • the effective area that is the area where the touch position is to be detected is limitedly set in the touch panel 3 based on the detected touch position. Therefore, avoiding useless detection can reduce power consumption and improve detection sensitivity of a touch operation.
  • the operation of the touch panel controller 4 and the operation of the area setting unit 8 are repeatedly performed at a predetermined frame rate (for example, 120 Hz).
  • the effective area calculation unit 81 sequentially confirms whether the “spot driving mode” or the “entire detection mode” is in operation (step # 4). Good. For example, the effective area calculation unit 81 may perform this check after step # 2, and then perform an operation corresponding to each mode until some instruction is input from the user or the like.
  • the size (for example, WD_D and WD_S) of the effective area set by the area setting unit 8 may be a fixed value or a variable value.
  • the size of the effective area is set to a variable value, when the area setting unit 8 sets a new effective area having a size corresponding to the moving speed of the touch position, the next touch position is included in the new effective area. Since possibility can be made high, it is preferable.
  • FIG. 37 is a diagram showing another example of the effective area setting method in the first operation example.
  • FIG. 8 illustrates a case where the touch position in the current frame is (Xpa, Ypa) and the touch position in the next frame is (Xpb, Ypb). Further, the moving speed in the X direction of the touch position in the current frame is Vx, the moving speed in the Y direction is Vy, and the frame rate is f.
  • the area setting unit 8 may obtain the touch position variation amount by storing the sequentially obtained touch positions in the storage unit 82, and obtain the touch position movement speed in the current frame based on the variation amount. .
  • the area setting unit 8 does not necessarily need to set an effective area centered on the touch position. For example, when a touch position is detected near the edge of the touch panel 3, the area setting unit 8 may set an effective area where the touch position is biased toward the edge. The area setting unit 8 may set an effective area based on the moving direction of the touch position. For example, the area setting unit 8 may set an effective area where the touch position is biased in the direction opposite to the moving direction of the touch position.
  • a touch panel system 1r shown in FIG. 30 has a plurality of touch panels 3 on the touch panel 3 because the touch panel controller 4 detects a touch position based on a difference distribution of capacitance of the touch panel 3. Even if there is a touch position, each touch position can be detected separately (multi-touch can be supported). Therefore, hereinafter, an operation example (second operation example) of the touch panel system 1r corresponding to multi-touch will be described.
  • the touch panel controller 4 can detect a plurality of touch positions and the area setting unit 8 can set an effective area based on the plurality of touch positions.
  • the description of the first operation example is appropriately referred to, and the detailed description thereof is omitted.
  • FIG. 38 is a block diagram illustrating an example of an effective area set in the touch panel 3 in the second operation example.
  • FIG. 38 illustrates the effective areas A1 and A2 set when the two touch positions are separated on the touch panel 3.
  • Each of the effective areas A1 and A2 illustrated in FIG. 38 is set as a partial area in the touch panel 3.
  • Each of the drive line 35r1 and the sense line 33r1 passes through the effective area A1, and each of the drive line 35r2 and the sense line 33r2 (thick solid line in the drawing) passes through the effective area A2.
  • each of the detection regions X formed by the drive line 35r1 and the sense line 33r1 is at least partially included in the effective region A1
  • each of the detection regions X formed by the drive line 35r2 and the sense line 33r2 is at least one of the detection regions X. Part is included in the effective area A2.
  • the drive line driving circuit 5 includes a drive line 35r1 passing through the effective area A1 and a drive line 35r2 passing through the effective area A2.
  • a drive signal is applied to each of.
  • the drive line drive circuit 5 does not apply a drive signal to each drive line that does not pass through any of the effective areas A1 and A2.
  • FIG. 39 is a diagram showing an example of a specific drive method of the drive line by the drive line drive circuit in the second operation example.
  • the drive line drive circuit 5 has the unique drive signal (see FIG. 32) for each of the drive line 35r1 passing through the effective area A1 and the drive line 35r2 passing through the effective area A2. ) Is applied. Further, the drive line drive circuit 5 suppresses the signal level of the drive line from changing with time by grounding each drive line that does not pass through either of the effective areas A1 and A2.
  • the drive line driving circuit 5 selectively drives the drive lines 35r1 and 35r2 passing through the effective areas A1 and A2, thereby preventing the drive line 35 from being driven unnecessarily. can do. For this reason, it is possible to reduce the power consumption for driving the drive line 35 and to suppress the generation of noise and improve the detection sensitivity of the touch operation. Moreover, the drive position 35r1 and 35r2 are limitedly driven, so that the touch position detection accuracy in the touch panel controller 4 can be improved.
  • FIG. 40 is a block diagram illustrating an example of a specific operation of the amplifying unit in the second operation example. 40 is the same as the amplifier 71 (see FIG. 33) described in the first operation example.
  • the open / close switch 712 to which the respective signals of the sense line 33r1 passing through the effective region A1 and the sense line 33r2 passing through the effective region A2 are supplied becomes conductive.
  • the respective signals of the sense line 33r1 passing through the effective area A1 and the sense line 33r2 passing through the effective area A2 are amplified by the amplifier 711 and output from the amplifying unit 71.
  • the open / close switch 712 to which the signal of the sense line that does not pass through any of the effective areas A1 and A2 is turned off. As a result, the signal on the sense line that does not pass through any of the effective areas A1 and A2 is not amplified by the amplifier 711 and is not output from the amplifier 71.
  • the amplifier 71 selectively amplifies the signals of the sense lines 33r1 and 33r2 passing through the effective regions A1 and A2, thereby reducing the power consumption required for the amplification of the signals of the sense line 33. become.
  • FIG. 41 is a block diagram illustrating an example of a specific operation of the selection acquisition unit in the second operation example. 41 is the same as the signal acquisition unit 72 (see FIG. 34) described in the first operation example.
  • the branch switch 721 can be connected to terminals corresponding to the sense line 33r1 passing through the effective area A1 and the sense line 33r2 passing through the effective area A2. Thereby, each of the signal of the sense line 33r1 passing through the effective region A1 amplified by the amplification unit 71 and the signal of the sense line 33r2 passing through the effective region A1 amplified by the amplification unit 71 are output to the subsequent stage.
  • the branch switch 721 is not connected to a terminal corresponding to a sense line through which neither of the effective areas A1 and A2 passes. As a result, the signal of the sense line that does not pass through any of the effective areas A1 and A2 is not output to the subsequent stage.
  • the signal acquisition unit 72 selectively acquires the signals of the sense lines 33r1 and 33r2 passing through the effective regions A1 and A2 and outputs the signals in a time-sharing manner. It is possible to prevent a signal from being output. Therefore, it is possible to reduce the power consumption required for the processing of the subsequent stage of the signal acquisition unit 72 (for example, the AD conversion unit 73, the decoding unit 58, and the coordinate detection unit 42).
  • the AD conversion unit 73 converts the analog signal output from the signal acquisition unit 72 into a digital signal
  • the decoding unit 58 determines the difference in capacitance of the touch panel 3 (effective areas A1, A2) based on the digital signal.
  • the distribution is obtained, and the coordinate detection unit 42 detects the touch position on the touch panel 3 (effective areas A1, A2) by referring to the difference distribution, and generates touch information.
  • the decoding unit 58 and the coordinate detection unit 42 are not only on the effective areas A1 and A2, but on the area through which the drive line 35r1 and the sense line 33r2 pass, and on the area through which the drive line 35r2 and the sense line 33r1 pass, It is also possible to detect the touch position.
  • the touch panel controller 4 can prevent unnecessary signal processing by selectively processing the signals of the sense lines 33r1 and 33r2 passing through the effective areas A1 and A2. Therefore, it is possible to reduce power consumption for signal processing. Further, the detection accuracy of the touch position can be improved by limitedly processing the signals of the sense lines 33r1 and 33r2 passing through the effective areas A1 and A2.
  • FIG. 42 is a flowchart illustrating an example of a specific operation of the region setting unit in the second operation example.
  • FIG. 43 is a diagram illustrating an example of an effective area setting method in the second operation example.
  • the position of the sense line 33 in the alignment direction (vertical direction in FIG. 43, the X direction) is X
  • the alignment direction of the drive line 35 (FIG.
  • the position in the touch panel 3 is represented by the coordinates (X, Y), the coordinates of the upper left corner of the touch panel 3 are (0, 0), and the position of the lower right corner Let the coordinates be (n, m).
  • the coordinates of the upper left corner of the effective area Ai are (Xsi, Ysi), and the coordinates of the lower right corner of the effective area Ai are (Xei, Yei).
  • I is a number for identifying effective area and effective area information, and takes a value of 1 or more and max or less (max is a natural number of 2 or more). That is, max is an upper limit value of the number of effective areas that can be set by the area setting unit 8, and may be a number equal to the number of touch positions that can be detected by the touch panel controller 4, for example. As described above, when the upper limit (max) is set for the number of valid areas that can be set by the area setting unit 8, the calculation amount of the area setting unit 8 becomes excessive, or the total number of effective areas set by the area setting unit 8. Since it becomes possible to suppress that an area becomes large too much, it is preferable.
  • the effective area A1 is set with the touch position (Xp1, Yp1) as the center, the length in the X direction is set as WD_S1, the length in the Y direction is set as WD_D1, and the effective area A2 is set in the touch position (Xp2). , Yp2), the length in the X direction is set as WD_S2, and the length in the Y direction is set as WD_D2.
  • the touch position Xp1, Yp1
  • Yp2 the length in the X direction
  • the length in the Y direction is set as WD_D2.
  • the effective area calculation unit 81 acquires touch information generated by the touch panel controller 4 (step # 13). At this time, the effective area calculation unit 81 confirms the parameters stored in the register 821 of the storage unit 82 to determine whether the “spot driving mode” (first mode) or the “entire detection mode” (second mode) Mode) (step # 14).
  • step # 17, YES When new touch information is output (step # 17, YES), the process returns to step # 13 to acquire the touch information. On the other hand, when new touch information is not output (step # 17, NO), the operation is terminated.
  • step # 14 the effective area calculation unit 81 performs the above-described “entire detection mode”. The same operation as in the case is performed (steps # 15 to # 17). As a result, since the effective area is set on the entire surface of the touch panel 3, whichever position on the touch panel 3 becomes the touch position next time, the touch panel controller 4 can detect the touch position.
  • the effective area calculation unit 81 includes the touch position.
  • Xsi Xpi-WD_Si / 2
  • Ysi Ypi-WD_Di / 2
  • Xei Xpi + WD_Si / 2
  • Yei Ypi + WD_Di / 2
  • num is the number of effective areas to be set by the effective area calculation unit 8, and may be the same as the number of touch positions calculated by the touch panel controller 4, for example.
  • the effective area calculation unit 81 can set new effective areas A1 to Anum that are likely to include the touch position next.
  • step # 17, YES When new touch information is output (step # 17, YES), the process returns to step # 13 to acquire the touch information. On the other hand, when new touch information is not output (step # 17, NO), the operation is terminated.
  • the area setting unit 8 can set an effective area.
  • an effective area that is an area where the touch position should be detected is limitedly set in the touch panel 3 based on the detected touch positions. Therefore, avoiding useless detection can reduce power consumption and improve detection sensitivity of a touch operation.
  • the operation of the touch panel controller 4 and the operation of the area setting unit 8 are repeatedly performed at a predetermined frame rate (for example, 120 Hz).
  • the effective area calculation unit 81 sequentially confirms whether the “spot driving mode” or the “entire detection mode” is in operation (step # 14), the confirmation may not be performed sequentially. Good. For example, the effective area calculation unit 81 may perform this check after step # 12, and then perform an operation corresponding to each mode until some instruction is input from the user or the like.
  • a new effective area that is the entire surface of the touch panel 3 may be set. Specifically, for example, in FIG. 42, it is determined whether or not it is a predetermined timing before performing step # 18. If it is the predetermined timing, step # 15 is performed, and if not, step # 18 is performed. Also good.
  • the touch operation is performed at another place on the touch panel 3. Even if it is performed, since the effective area that is the entire surface of the touch panel 3 is set at a predetermined timing, the touch panel controller 4 can detect the touch position.
  • the size of the effective area set by the area setting unit 8 may be the same, but may be different for each effective area (for each i).
  • the size of the effective area set by the area setting unit 8 (for example, WD_Di and WD_Si) may be a fixed value or a variable value.
  • the area setting unit 8 sets a new effective area having a size corresponding to the moving speed of the touch position. Then, since the possibility that the position where the touch position is detected next is included in the new effective area can be increased, it is preferable.
  • FIG. 44 is a diagram illustrating another example of the effective area setting method in the second operation example.
  • the first touch position in the current frame is (Xp1a, Yp1a)
  • the second touch position is (Xp2a, Yp2a)
  • the first touch position in the next frame is (Xp1b, Yp1b)
  • the case where the touch position of 2 is (Xp2b, Yp2b) is illustrated.
  • the moving speed in the X direction of the first touch position in the current frame is Vx1
  • the moving speed in the Y direction is Vy1
  • the moving speed in the X direction of the second touch position in the current frame is Vx2
  • the moving speed in the Y direction is It is assumed that Vy2 and the frame rate is f.
  • the area setting unit 8 includes the first touch position (Xp1b, Yp1b) in the next frame based on the first touch position (Xp1a, Yp1a) and the moving speed (Vx1, Vy1) in the current frame. Set a new effective area. That is, the region setting unit 8 sets a new effective region so that WD_S1 ⁇ 2 ⁇ Vx1 / f and WD_D1 ⁇ 2 ⁇ Vy1 / f. Similarly, the area setting unit 8 includes the second touch position (Xp2b, Yp2b) in the next frame based on the second touch position (Xp2a, Yp2a) and the moving speed (Vx2, Vy2) in the current frame. Thus, a new effective area is set. That is, the region setting unit 4 sets a new effective region so that WD_S2 ⁇ 2 ⁇ Vx2 / f and WD_D2 ⁇ 2 ⁇ Vy2 / f.
  • the region setting unit 8 obtains a variation amount of each touch position by storing each sequentially obtained touch position in the storage unit 82, and moves each touch position in the current frame based on the variation amount. You may ask for speed.
  • the area setting unit 8 does not necessarily need to set each effective area centered on each touch position. For example, when a certain touch position is detected in the vicinity of the edge of the touch panel 3, the area setting unit 8 may set an effective area where the certain touch position is biased toward the edge. The area setting unit 8 may set an effective area based on the moving direction of the touch position. For example, the region setting unit 8 may set an effective region in which a certain touch position is biased in a direction opposite to the moving direction of the certain touch position.
  • FIG. 45 is a block diagram showing another example of the effective area set in the touch panel in the second operation example.
  • FIG. 45 illustrates a case where three touch positions are separated from each other on the touch panel 3.
  • the area setting unit 8 can set effective areas A1 to A3 corresponding to the respective touch positions (see FIG. 42). .
  • the drive line drive circuit 5 may selectively drive the drive line 35r1 passing through the effective area A1, the drive line 35r2 passing through the effective area A2, and the drive line 35r3 passing through the effective area A3.
  • the touch panel controller 4 selectively processes the signals of the sense line 33r1 passing through the effective area A1, the sense line 33r2 passing through the effective area A2, and the sense line 33r3 passing through the effective area A3.
  • the drive lines 35r1 to 35r3 and the sense lines 33r1 to 33r3 are indicated by thick solid lines in the drawing.
  • the touch panel system 1r shown in FIG. 30 can cope with multi-touch having three or more touch positions on the touch panel 3 in the same manner as when there are two touch positions (see FIGS. 38 to 44). it can.
  • FIG. 46 is a block diagram illustrating another example of effective areas set in the touch panel in the second operation example.
  • FIG. 46 illustrates a case where two touch positions are close to each other on the touch panel 3.
  • the area setting unit 8 can set effective areas A1 and A2 in which some areas overlap.
  • the drive line drive circuit 5 selectively selects a drive line 35r11 that passes only through the effective area A1, a drive line 35r22 that passes through only the effective area A2, and a drive line 35r12 that passes through both the effective areas A1 and A2.
  • the touch panel controller 4 receives the signals of the sense line 33r11 passing through only the effective area A1, the sense line 33r22 passing through only the effective area A2, and the sense line 33r12 passing through both the effective areas A1 and A2. Selectively process.
  • the drive lines 35r11, 35r22, and 35r12 and the sense lines 33r11, 33r22, and 33r22 are indicated by thick solid lines in the drawing.
  • FIG. 47 is a diagram showing another example of a specific driving method of the drive line by the drive line driving circuit in the second operation example.
  • FIG. 47 assumes a case where the effective areas A1 and A2 shown in FIG. 46 are set.
  • the drive line drive circuit 5 includes a drive line 35r11 that passes through only the effective area A1, a drive line 35r22 that passes through only the effective area A2, a drive line 35r12 that passes through both of the effective areas A1 and A2,
  • the above-described unique drive signal (see FIG. 32) is applied to each of the above. Further, the drive line drive circuit 5 suppresses the signal level of the drive line from changing with time by grounding each drive line that does not pass through either of the effective areas A1 and A2.
  • FIG. 48 is a block diagram showing another example of the specific operation of the amplifying unit in the second operation example. Note that the amplifying unit 71 shown in FIG. 48 is the same as the amplifying unit 71 shown in FIG. FIG. 48 assumes a case where the effective areas A1 and A2 shown in FIG. 46 are set.
  • the respective signals of the sense line 33r11 passing through only the effective region A1, the sense line 33r22 passing through only the effective region A2, and the sense line 33r12 passing through both the effective regions A1 and A2 are supplied.
  • the open / close switch 712 is turned on.
  • the amplifier 711 amplifies the signals of the sense line 33r11 that passes only through the effective region A1, the sense line 33r22 that passes through only the effective region A2, and the sense line 33r12 that passes through both the effective regions A1 and A2.
  • the open / close switch 712 to which the signal of the sense line that does not pass through any of the effective areas A1 and A2 is turned off.
  • the signal on the sense line that does not pass through the effective area A is not amplified by the amplifier 711 and is not output from the amplifying unit 71.
  • FIG. 49 is a block diagram showing another example of the specific operation of the selection acquisition unit in the second operation example. Note that the signal acquisition unit 72 shown in FIG. 49 is the same as the signal acquisition unit 72 shown in FIG. FIG. 49 assumes that the effective areas A1 and A2 shown in FIG. 46 are set.
  • the branch switch 721 includes a sense line 33r11 that passes only through the effective region A1, a sense line 33r22 that passes through only the effective region A2, and a sense line 33r12 that passes through both the effective regions A1 and A2. It can be connected to a terminal corresponding to.
  • Each of the signals is output to the subsequent stage.
  • the branch switch 721 is not connected to a terminal corresponding to a sense line through which neither of the effective areas A1 and A2 passes. As a result, the signal of the sense line that does not pass through any of the effective areas A1 and A2 is not output to the subsequent stage.
  • the touch panel system 1r shown in FIG. 30 can cope with multi-touch when a plurality of touch positions on the touch panel 3 are close to each other in the same manner as when the touch positions are separated (see FIGS. 38 to 44). it can.
  • the area setting unit 8 substantially sets an effective area including each touch position. Note that, when the plurality of touch positions on the touch panel 3 are close to each other, the area setting unit 8 calculates effective area information so as to set a comprehensive effective area including each touch position. May be.
  • the area setting unit 8 may set an effective area based on the plurality of touch positions detected by the touch panel controller 4. Specifically, for example, the area setting unit 8 may set a comprehensive effective area including each touch position detected by the touch panel controller 4.
  • a projection type capacitive touch panel system has been exemplified.
  • the present invention is not limited to another projection type capacitive type, surface type capacitive type, Any type of touch panel system can be applied as long as it is a touch panel system capable of selective driving or selective processing, such as an optical type.
  • Embodiments 1 to 17 and the second feature of the first feature disclosed this time should be considered as illustrative in all points and not restrictive.
  • the scope of the present invention is shown not by the description of Embodiments 1 to 17 and the second feature in the first feature, but by the scope of claims, and all meanings within the scope and equivalents of the claims are within the scope of the present invention. Modifications are intended to be included within the scope of the present invention.
  • the present invention is applied to various touch-panel electronic devices such as a TV, a personal computer, a mobile phone, a digital camera, a portable game machine, an electronic photo frame, a portable information terminal, an electronic book, a home appliance, a ticket machine, an ATM, and a car navigation system. be able to. Further, the present invention can be applied to a large electronic device such as a display surface of a large display device or an electronic whiteboard.

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  • General Engineering & Computer Science (AREA)
  • Theoretical Computer Science (AREA)
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  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Position Input By Displaying (AREA)

Abstract

L'invention porte sur un système de panneau tactile qui comprend : un panneau tactile comprenant une pluralité de lignes d'excitation qui forment une capacité entre une pluralité de lignes de détection et d'autres lignes de détection qui sont placées de manière à croiser les lignes de détection susmentionnées ; un contrôleur de panneau tactile qui traite les signaux des lignes de détection ; et un circuit d'attaque de ligne d'excitation pour attaquer les lignes d'excitation en parallèle. Le contrôleur de panneau tactile comprend : une unité de soustraction pour calculer la différence entre les signaux de lignes de détection qui sont adjacentes l'une à l'autre ; une unité de décodage qui calcule la distribution différentielle de la capacité par calcul du produit interne de la séquence de code servant à attaquer les lignes d'excitation en parallèle et d'une différence qui correspond à la séquence de code ; une unité de détection tactile qui obtient des informations tactiles sur la base de la distribution différentielle de la capacité qui est calculée par l'unité de décodage ; et une unité de réglage de région qui règle une région active sur le panneau tactile sur la base des informations tactiles.
PCT/JP2012/063963 2012-05-30 2012-05-30 Système de panneau tactile et dispositif électronique WO2013179422A1 (fr)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2017056900A1 (fr) * 2015-10-01 2017-04-06 シャープ株式会社 Procédé de détection de capacité, procédé de détection de position, dispositif de commande de panneau tactile et dispositif électronique

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH08106358A (ja) * 1994-08-10 1996-04-23 Fujitsu Ltd タブレット機能付き液晶表示装置、アクティブマトリクス型液晶表示装置及びタブレット機能付き液晶表示装置の駆動方法
JP2010282539A (ja) * 2009-06-08 2010-12-16 Sanyo Electric Co Ltd 静電容量型タッチセンサ用の信号処理回路
JP2011128982A (ja) * 2009-12-18 2011-06-30 Wacom Co Ltd 指示体検出装置及び指示体検出方法

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8866789B2 (en) * 2007-01-16 2014-10-21 N-Trig Ltd. System and method for calibration of a capacitive touch digitizer system
JP4927216B1 (ja) * 2010-11-12 2012-05-09 シャープ株式会社 線形素子列値推定方法、静電容量検出方法、集積回路、タッチセンサシステム、及び電子機器

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH08106358A (ja) * 1994-08-10 1996-04-23 Fujitsu Ltd タブレット機能付き液晶表示装置、アクティブマトリクス型液晶表示装置及びタブレット機能付き液晶表示装置の駆動方法
JP2010282539A (ja) * 2009-06-08 2010-12-16 Sanyo Electric Co Ltd 静電容量型タッチセンサ用の信号処理回路
JP2011128982A (ja) * 2009-12-18 2011-06-30 Wacom Co Ltd 指示体検出装置及び指示体検出方法

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2017056900A1 (fr) * 2015-10-01 2017-04-06 シャープ株式会社 Procédé de détection de capacité, procédé de détection de position, dispositif de commande de panneau tactile et dispositif électronique

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