TWI552059B - Touch panel system and electronic device - Google Patents

Description

Touch panel system and electronic machine

The present invention relates to a touch panel system and an electronic device including the same, and more particularly to a touch panel system and an electronic device that can effectively eliminate noise (cancellation) generated by a display device or the like.

Recently, technology for mounting a touch panel system on vending machines such as information devices and automatic ticket vending machines for various electronic devices such as smart phones is rapidly developing.

The structure of such a touch panel system generally stacks the touch panel on the upper portion (front side) of the display device. Therefore, the sensor disposed on the touch panel is not only affected by noises such as clocks generated by the display device, but also susceptible to other external noise. This kind of noise system causes the detection sensitivity of the touch operation to decrease.

Patent Document 1 describes a touch panel system (coordinate input device) that solves such noise countermeasures. The touch panel system of Patent Document 1 is provided with a noise processing unit for eliminating noise. FIG. 19 is a block diagram showing the noise processing unit 100 provided in the touch panel system of Patent Document 1. As shown in FIG. 19, 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). Furthermore, the filtering unit 101 extracts the 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 the noise signal whose phase is inverted by 180 degrees to include the input to the filtering. The input signal of the noise signal of the part 101.

Therefore, in the touch panel system of Patent Document 1, 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, the inversion signal of the same level as the noise component is added to the noise component included in the input signal from the sensor. Thereby, the noise overlapping in the input signal from the sensor is cancelled. Thereby, the influence of the noise included in the input signal from the sensor can be reduced.

[Advanced technical literature] [Patent Literature]

[Patent Document 1] Japanese Laid-Open Patent Publication No. 2001-125744 (published on May 11, 2001)

However, the touch panel system of Patent Document 1 has a problem that noise other than the AC signal component cannot be eliminated.

Specifically, as described above, the touch panel system of Patent Document 1 processes the input signal from the maker to the AC signal component included in the input signal as noise. After the AC signal is extracted by the filter unit 101, the phase is inverted by 180 degrees by the logic inverting unit 102. Next, in the adding unit 103, the inverted signal is added to the input signal including the AC signal component. Therefore, in Patent Document 1, the processing of extracting the AC signal component by the filter unit 101 is most important in the noise processing.

However, Patent Document 1 does not disclose the configuration of the filter unit 101 in detail. Therefore, the degree to which the touch panel system of Patent Document 1 can eliminate noise is not yet clear. Further, Patent Document 1 treats an AC signal component included in an analog signal as noise. That is, the touch panel system of Patent Document 1 is supposed to substantially eliminate only the pulse noise, and the noise system other than the pulse noise is not eliminated. Therefore, it is impossible to surely remove a variety of noises other than pulse noise.

Furthermore, it is also desirable to reduce the power consumption of the touch panel system or to improve the detection sensitivity of the touch operation.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a touch panel system and an electronic device that can reliably eliminate various types of noise, reduce power consumption, and improve the detection sensitivity of a touch operation.

In order to solve the above problems, the touch panel system of the present invention includes a touch panel including: a plurality of sensing lines; and a plurality of roots formed by intersecting the sensing lines and forming an electrostatic capacitance with the sensing lines a driving line driving circuit that drives the driving line in parallel; a touch panel controller that processes the sensing line signal and generates touch information; and an area setting unit that performs the touch based on the touch information An effective area is set in the panel; and the touch panel controller includes: a subtraction unit that calculates a signal difference of the sensing lines adjacent to each other; and a decoding unit that sequentially drives the code sequence of the driving line by parallel operation and The difference product of the difference output sequence corresponding to the code sequence calculated by the subtraction unit calculates a difference distribution of the capacitance; and the touch detection unit generates the touch based on the capacitance difference distribution calculated by the decoding unit Information; the above-mentioned area setting department will be set on the above touch surface based on the above touch information. The effective area of the board is updated to set a new effective area; and the touch panel system performs the first operation and the driving of the driving line by the driving line driving circuit to selectively drive the effective area The touch panel controller selectively processes at least one of a second operation of the signal passing through the sensing line of the active area currently set.

According to the above configuration, the subtraction unit acquires the differential signal value between the adjacent sensing lines. That is, the difference between adjacent sensing lines with higher noise correlation is obtained. Thereby, the output signal of the self-sensing line eliminates the noise part, and the original signal of the touch operation is taken. Therefore, various kinds of noises reflected by the touch panel can be surely removed (removed). Further, according to the above configuration, the touch panel is driven in parallel, and the decoding unit decodes the capacitance difference value calculated by the subtraction unit. Thereby, since the obtained electrostatic capacitance code is multiplied by the code length (N times), the electrostatic capacitance signal strength can be improved without depending on the number of driving lines. In addition, if the signal intensity is the same as in the previous method, the number of driving of the driving line can be reduced, and power consumption can be reduced.

Furthermore, according to the above configuration, the drive line can be prevented from being driven uselessly by the first operation. Therefore, the power consumed by the driving line driving can be reduced, noise generation can be suppressed, and the detection sensitivity of the touch operation can be improved. In addition, the detection accuracy of the touch position can be improved by driving the drive line in a limited manner. Moreover, by the second operation, useless signal processing can be prevented. Therefore, the power consumption of the signal processing can be reduced. In addition, the detection accuracy of the touch position can be improved by performing a limited processing on the sensing line signal passing through the effective area.

In the touch panel system of the present invention, a switch is further included, which is directed to The sensing line Sn selected by the sensing line and the two sensing lines (the sensing line Sn+1 and the sensing line Sn-1) adjacent to the sensing line Sn are used to calculate the signal of the sensing line Sn and the sensing line Sn+1. The first difference ((Sn+1)-Sn) of the difference of the signal, or the second difference (Sn-(Sn-1)) of the difference between the signal of the sensing line Sn and the signal of the sensing line Sn-1 And switching the signal input to the sensing line of the above-mentioned subtraction unit.

In the touch panel system of the present invention, the switch may include two terminals and be configured to select one of the terminals; and the code sequence for driving the driving lines in parallel may drive the first to the Mth as shown in the following manner. No. of the above drive line (component 1 or -1): d ₁ = (d ₁₁ , d ₁₂ , ..., d _1N )

d ₂ = (d ₂₁ , d ₂₂ ,...,d _2N )

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.

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d _M = (d _M1 , d _M2 , ..., d _MN ), which will correspond to the above differential output sequence "S _j,P (j=1,...,[L/2],P) =1, 2) (L is the number of sensing lines, the integer part of [n] = n)" is defined as: S _{j, 1} : when the switch SW selects one terminal, the output sequence for d ₁ ~ d _M ; S _{j, 2} : When the switch SW selects the other terminal, the output sequence of d ₁ to d _M ; the decoding unit calculates the inner product of the code sequence of the drive line and the differential output sequence corresponding to the code sequence.

In the touch panel system of the present invention, the subtraction unit may include a first AD conversion unit that converts the analog signal into a digital signal, and the subtraction unit compares the first AD conversion unit with the analog line. After the signal is converted into a digital signal, the first difference and the second difference are calculated by calculating the difference between the digital signals.

According to the above configuration, after the analog signal output from the touch panel is converted into a digital signal, noise reduction can be eliminated by performing subtraction processing.

In the touch panel system of the present invention, the subtraction unit may include a second AD conversion unit that converts the analog signal into a digital signal, and the subtraction unit calculates the difference between the analog signals obtained from the sensing line by using the subtraction unit. The difference between the analog signals is converted into a digital signal by the second AD conversion unit, and the first difference and the second difference are calculated.

According to the above configuration, the analog signal outputted from the touch panel is directly subjected to the analog signal reduction processing, and then converted into a digital signal to remove the noise.

In the touch panel system of the present invention, the subtracting unit preferably includes a fully differential amplifier that calculates the first difference and the first by calculating a difference between the analog signals obtained from the sensing lines adjacent to each other 2 differential.

According to the above configuration, the analog signal outputted by the analog signal outputted by the touch panel is directly subjected to the analog signal subtraction processing by the fully differential amplifier, and then converted into a digital signal to remove the noise.

The touch panel system of the present invention may further include: a non-touch operation information storage unit that memorizes a difference distribution of the electrostatic capacitance calculated by the decoding unit during a non-touch operation; and a correction unit, The difference distribution of the electrostatic capacitance calculated by the decoding unit during the touch operation is reduced. The difference distribution of the electrostatic capacitances stored in the non-touch operation in the information memory unit when the non-touch operation is performed.

According to the above configuration, the information storage unit stores the difference distribution of the electrostatic capacitance during the non-touch operation decoded by the decoding unit during the non-touch operation. Moreover, the correction unit subtracts the difference distribution of the electrostatic capacitance during the non-touch operation in the information memory unit during the non-touch operation from the difference distribution of the electrostatic capacitance during the touch operation. That is, the correction unit calculates (the difference distribution of the electrostatic capacitance during the touch operation) - (the differential distribution of the electrostatic capacitance during the non-touch operation). Therefore, the internal offset of the touch panel can be eliminated.

In the touch panel system of the present invention, the touch detection unit may determine whether there is a touch operation based on a difference between the sense line signals adjacent to each other calculated by the subtraction unit and a comparison result between the positive and negative threshold values. .

According to the above configuration, the touch detection unit determines the presence or absence of the touch operation based on the signal difference between the sensing lines adjacent to each other after the noise is removed. Therefore, the presence or absence of the touch operation can be correctly judged.

In the touch panel system of the present invention, the touch detection unit may create the electrostatic capacitance based on a difference between the sense line signals adjacent to each other calculated by the subtraction unit and a comparison between the positive and negative threshold values. The difference distribution is a three-valued increase/decrease table, and the increase/decrease table is converted into a binary image, thereby generating the touch information.

According to the above configuration, after the noise signal is removed, the difference between the adjacent sensing line signals is input to the touch detecting unit. The touch detection unit uses the difference between the sense line signals adjacent to each other and the comparison between the positive and negative threshold values stored in the touch detection unit to create a three-valued difference distribution of the sense line signals. Increase or decrease table. Further, the touch detection unit converts the increase/decrease table into a binary image by binarizing the increase/decrease table. Thereby, the touch candidate position is captured in the converted binary image. Therefore, based on the binary image, by recognizing the touch information (touch size, touch position, etc.), in addition to determining whether the touch operation is present, the touch information can be more correctly recognized.

Preferably, the touch panel system of the present invention further includes: an adding unit that adds the difference calculated by the subtracting unit; and the touch panel includes at least one auxiliary sensing line, and the subtracting unit further calculates the pair The third difference between the sensing line and the sensing line adjacent to the sub sensing line, the adding unit adds the first difference, the second difference, and the third difference.

According to the above configuration, the sensing line and the sub sensing line are provided in the same surface (the same surface) of the touch panel. Therefore, any of the output signals of the sensing line and the auxiliary sensing line include various kinds of noise signals reflected by the touch panel. Furthermore, the subtraction unit obtains the difference between the output signal of the sensing line including the signal of the touch operation and the noise signal, and the output signal of the auxiliary sensing line including the noise signal. Thereby, the noise component is removed from the output signal of the sensing line, and the original signal of the touch operation is captured. Therefore, it is possible to surely remove (eliminate) various noises reflected by the touch panel. Furthermore, the signal (noise signal) of the secondary sensing line can be removed from the output signal of each sensing line. Thereby, the noise can be removed more surely.

Further, according to the above configuration, the sensing line is adjacent to the sub sensing line, that is, the sensing line and the sub sensing line are arranged closest to each other, and the sensing line and the sub sensing line are arranged in substantially the same condition. Therefore, the output included in the secondary sensing line The noise signal value in the signal can be regarded as the same as the noise signal value contained in the output signal of the sensing line. Thereby, the noise reduction component reflected by the touch panel can be surely eliminated by the subtraction processing of the subtraction unit. Thereby, the detection sensitivity of the touch operation can be further improved.

In the touch panel system of the present invention, the subtraction unit may include a third AD conversion unit for converting the analog signal into a digital signal; and the subtraction unit may use the third AD conversion unit from the sensing line or After the analog signal obtained by the sub sensing line is converted into a digital signal, the first difference, the second difference, and the third difference are calculated by calculating a difference between the digital signals.

According to the above configuration, the noise can be removed by converting the analog signal output from the touch panel into a digital signal and performing a subtraction process.

In the touch panel system of the present invention, the subtraction unit may include a fourth AD conversion unit that converts the analog signal into a digital signal, and the subtraction unit calculates an analog signal obtained from the sensing line or the sub sensing line. After the difference, the difference between the analog signals is converted into a digital signal by the fourth AD conversion unit, and the first difference, the second difference, and the third difference are calculated.

According to the above configuration, after the analog signal is directly subtracted from the analog signal output from the touch panel, the analog signal is converted into a digital signal to remove the noise.

In the touch panel system of the present invention, the subtracting unit preferably further includes: a fully differential amplifier that calculates the first difference and the first difference by calculating a difference between the analog signals obtained from the sensing line or the sub sensing line Second difference The third difference is the same as the above.

According to the above configuration, the analog signal output from the touch panel is directly subjected to the analog signal subtraction processing by the fully differential amplifier, and then converted into a digital signal to remove the noise.

In the touch panel system of the present invention, the full differential amplifier preferably has an input common mode voltage range of rail-to-rail operation.

According to the above configuration, a fully differential amplifier that can perform a rail-to-rail operation is included. Thereby, the fully differential amplifier can operate within the voltage range of the power supply voltage (Vdd) to GND. Thus, the output signal from the fully differential amplifier does not cause an output saturation problem.

In the touch panel system of the present invention, the addition unit may perform the addition processing in order from the closer to the sub-sensing line, and use the addition result for the next addition processing.

According to the above configuration, the addition unit sequentially performs the addition processing in the direction away from the sub sensing line while using the addition result. Thereby, the addition processing speed can be increased.

In the touch panel system of the present invention, the sub sensing line may not detect the touch operation of the touch panel.

According to the above configuration, since the signal of the touch operation is not detected by the sub sensing line, the output signal of the sub sensing line does not include the signal of the touch operation. Thereby, the subtraction processing by the subtraction unit does not reduce the signal value of the touch operation. That is, the noise component can be removed without reducing the touch operation signal detected by the sensing line. Therefore, the detection sensitivity of the touch operation can be further improved.

In the touch panel system of the present invention, the sub sensing line may be disposed on an area of the touch panel that is not touch-operated.

According to the above configuration, the sub sensing line is provided in a region (touch area) in which the user performs the touch operation. Therefore, the secondary sensing line detects the noise reflected on the touch panel when the user does not touch the operation, but does not detect the signal of the touch operation. Therefore, the secondary sensing line can surely avoid detecting touch operations.

That is, according to the above configuration, since the signal of the touch operation is not detected by the sub sensing line, the signal of the touch operation is not included in the output signal of the sub sensing line. Thereby, the subtraction processing by the subtraction unit does not reduce the signal value of the touch operation. That is, the noise component can be eliminated without reducing the touch operation signal detected by the sensing line. Therefore, the detection sensitivity of the touch operation can be further improved.

In the touch panel system of the present invention, it is preferable that the drive line drive circuit applies the code sequence unique to each of the drive lines to each of the drive lines passing through the effective area, and is effective for failing to pass the above-described The above-described respective drive lines of the area are not assigned to the above code sequence.

According to the above configuration, the touch panel controller more easily recognizes the variation of the sensing signal generated by the touch operation.

In the touch panel system of the present invention, the touch panel controller preferably further includes: an amplifying portion for selectively amplifying the signal passing through the sensing line of the effective area.

According to the above configuration, useless amplification of the sensing line signal can be prevented. Thereby, the power consumption of the induction line signal amplification can be reduced.

In the touch panel of the present invention, the touch panel controller is preferably further packaged The signal acquisition unit selectively acquires the sensing line signal passing through the effective area and outputs the time division.

According to the above configuration, the useless signal output in the subsequent stage of the signal acquisition unit can be prevented. Therefore, the power consumption of the subsequent processing of the signal acquisition unit can be reduced.

In the touch panel system of the present invention, the area setting unit preferably sets the new effective area including the touch position which is one of the touch information.

According to the above configuration, the area setting unit can then set a new effective area including a higher possibility of the touch position.

In the touch panel system of the present invention, the area setting unit preferably sets the new effective area of a size corresponding to the moving speed of the touch position, which is one of the touch information.

According to the above configuration, the area setting unit can then set a new effective area including a higher possibility of the touch position.

In the touch panel system of the present invention, preferably, the area setting unit sets the new effective area that is the entire surface of the touch panel when the touch panel controller does not detect the touch operation.

According to the above configuration, the touch panel controller can detect the touch position even if any position on the touch panel becomes the touch position.

In the touch panel system of the present invention, when the first mode is selected, the area setting unit may set the new effective area based on the touch position of one of the touch information, and when the second mode is selected The area setting unit continuously sets the new effective area that is the entire surface of the touch panel.

According to the configuration described above, for example, in accordance with the installation environment or the use environment of the touch panel system, the first mode in which the power consumption is reduced and the sensitivity of the touch operation detection can be improved, and the touch can be detected from the entire surface of the touch panel. In any mode of the second mode of the position, the touch panel system is operated.

In the touch panel system of the present invention, preferably, when the touch information includes a plurality of touch positions, the area setting unit sets the new effective area based on the plurality of touch positions.

According to the above configuration, in the case where the touch panel controller detects a plurality of touch positions (multi-touch), the area setting unit can also set the effective area.

In the touch panel system of the present invention, preferably, the area setting unit sets a plurality of new effective areas corresponding to the touch positions when the new effective area is set based on the plurality of touch positions.

According to the above configuration, a gap (a region of the non-effective area) can be provided between the effective areas set by the area setting unit. Therefore, the total area of the effective area set by the area setting unit can be reduced.

In the touch panel system of the present invention, it is preferable that an upper limit value is set for the number of the new effective areas set by the area setting unit.

According to the above configuration, the number of effective regions that can be set by the region setting unit is limited to the upper limit value or lower. Therefore, it is possible to suppress an excessive amount of calculation of the area setting unit and an excessively large total area of the effective area set by the area setting unit.

In the touch panel system of the present invention, it is preferable that the area setting unit sets a new effective area that is the entire surface of the touch panel at each specific timing.

According to the above configuration, the area setting unit corresponds to the use of the touch panel The controller sequentially detects the touch position to sequentially set the effective area (point drive), and then performs touch operation on other parts of the touch panel, and also sets the touch panel as a whole at a specific timing. The effective area, so that the touch panel controller can also detect the touch position.

In the touch panel system of the present invention, the code sequence may also be an orthogonal sequence or an M sequence.

Preferably, the touch panel system of the present invention further includes a display device, and the touch panel is disposed on a front surface of the display device.

According to the above configuration, since the touch panel is provided on the front surface of the display device, the noise generated by the display device can be surely eliminated.

In the touch panel system of the present invention, the display device is preferably a liquid crystal display, a plasma display, or an organic EL display or a field emission display.

According to the above configuration, the display device is constituted by various displays that are mostly used in everyday electronic devices. Thereby, a highly versatile touch panel system can be provided.

In order to solve the above problems, the electronic device of the present invention includes any of the above touch panel systems.

Therefore, an electronic machine capable of surely removing (eliminating) various types of noise reflected by the touch panel can be provided.

As described above, the touch panel system of the present invention includes a subtraction unit that receives a signal from the main sensing unit and calculates a difference between adjacent sensing line signals. That is, the subtraction unit obtains a differential signal value between the sensing lines that have higher noise correlation and are adjacent to each other. From this, from the main sensor The noise signal is removed from the output signal, and the original signal of the touch operation is captured. Therefore, the effect of surely removing (eliminating) various types of noise reflected by the touch panel can be exerted.

In addition, the touch panel system of the present invention limits the effective area of the area where the touch position detection should be performed to the touch panel based on the detected touch position. Therefore, by avoiding useless detection, power consumption can be reduced and the detection sensitivity of the touch operation can be improved.

Hereinafter, embodiments of the present invention will be described based on the drawings. Further, although the embodiment of the present invention has both the first feature and the second feature described below, the first feature and the second feature will be described below for convenience of explanation.

<<1st feature>>

[Embodiment 1]

(1) The composition of the touch panel system 1

FIG. 1 is a schematic view showing a basic configuration of a touch panel system 1 according to a first 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 driving line driving circuit 5, and has a function of removing noise. Hereinafter, the side used by the user will be described as the front side (or upper side).

The display device 2 includes a display screen (display portion) not shown. Various icons for operation and text information corresponding to the operation instructions of the user are displayed on the display screen. The display device 2 is, for example, a liquid crystal display, a plasma display, an organic EL display, and a field emission display (FED; field Emission display). These displays are mostly used in everyday electronic devices, and thus can constitute a highly versatile touch panel system 1. The display device 2 can be of any configuration and is not particularly limited.

The touch panel 3 inputs various operation instructions by operating (touching) the surface of the touch panel 3 by a user's finger or a pen. The touch panel 3 is laminated on the front surface (upper portion) of the display device 2 so as to cover the display screen.

The touch panel 3 includes two sensors (one for each of the main sensor 31 and the sub sensor 32) disposed on the same surface (in the same plane). The main inductor 31 and the sub sensor 32 are disposed adjacent to each other. The main inductor 31 and the sub sensor 32 are both capacitive sensors. The touch panel 3 provided with the electrostatic capacitance type sensor has a high transmittance and durability.

The main sensor (main sensing portion) 31 is disposed in the touch operation area (touch area) of the touch panel 3 to detect the touch operation of the touch panel 3 by the user. Touch operations include double click operations, sliding operations, single click operations, and drag operations. The main inductor 31 is provided with an induction line 33 including a linear electrode. One end of the sensing 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 sensing line 33. That is, the 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 the noise component reflected by the touch panel 3 . The sub-sensor 32 is disposed in the area of the touch panel 3 that is not touch-operated (non-touch area). Therefore, the sub sensor 32 is not touched by the user through the touch operation, and only the various miscellaneous generated by the touch panel system 1 is detected. News. Thereby, the sub sensor 32 is different from the main sensor 31 in that the signal corresponding to the touch operation is not detected. That is, the sub sensor 32 is not touched by the user by the touch operation, and only the noise generated by the touch panel 3 is detected.

The sub sensor 32 has a sub sensing line 34 including a linear electrode. The secondary sensing line 34 is parallel to the sensing line 33 (extending in the same direction as the sensing line 33). One end of the secondary sensing line 34 is connected to the touch panel controller 4. Thereby, the signal detected by the sub sensor 32 is output to the touch panel controller 4 via the sub sensing line 34.

On the other hand, the touch panel 3 includes a driving line 35 that intersects the sensing line 33 and the sub sensing line 34 in an orthogonal manner. The drive line 35 is a wire electrode. An electrostatic capacitance is formed between the sensing line 33 or the intersection of the sub sensing line 34 and the driving line 35. That is, an electrostatic capacitance is formed between the sensing line 33 and the driving line 35 and between the sub sensing line 34 and the driving line 35. The drive line 35 is connected to the drive line drive circuit (sensor drive unit) 5, and when the touch panel system 1 is activated, a potential is applied to the drive line 35 at a certain period.

The sensing line 33, the sub sensing line 34, and the driving line 35 can be formed of a transparent wiring material such as ITO (Indium Thin Oxide). The sensing line 33, the secondary sensing line 34, and the driving line 35 may also be referred to as sensing electrodes of the touch panel 3.

Further, the drive line 35 is provided on a transparent substrate or a transparent film (not shown). Furthermore, the drive line 35 is covered by an insulating layer (not shown). The insulating layer 33 and the sub sensing line 34 are provided on the insulating layer. Thereby, the sensing line 33 or the auxiliary sensing line 34 and the driving line 35 are insulated from each other by the insulating layer and are capacitively coupled. The sensing line 33 and the sub sensing line 34 are covered by a protective layer (not shown). That is, in the touch panel 3, the protective layer is disposed on the most front 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 an electrostatic capacitance type sensor, the touch panel controller 4 detects the electrostatic capacitance generated by the touch panel 3. Specifically, the touch panel controller 4 detects a change in electrostatic capacitance between the sensing line 33 and the driving line 35 and a change in electrostatic capacitance between the auxiliary sensing line 34 and the driving line 35. The touch panel controller 4 includes a subtraction unit 41, a coordinate detecting unit 42 (touch detecting unit), and a CPU 43.

The subtraction unit 41 includes an input terminal (an input terminal for outputting the main inductor) for receiving a signal output from the autonomous sensor 31, and an input terminal (an input terminal for outputting the sub sensor) for receiving the slave The signal output by the sensor 32. The subtraction unit 41 subtracts the signal input to the input terminal for the sub-sensor output from the signal input to the input terminal for the main inductor output. The signal subjected to the subtraction processing by the subtraction unit 41 is output to the coordinate detecting unit 42. In addition, the signal input to the subtraction unit 41 can be a digital signal or an analog signal. In other words, the signal input to the subtraction unit 41 may be a signal corresponding to the configuration of the subtraction unit 41.

The coordinate detecting unit 42 detects the presence or absence of the information of the touch operation based on the signal subjected to the subtraction processing by the subtraction unit 41. For example, when the output signal value of the self-subtraction unit 41 reaches a certain threshold or more, the coordinate detecting unit 42 outputs a signal of the "touch" touch operation to the CPU 43. In the touch panel system 1, since the main sensor 31 is singular, the coordinate detecting unit 42 detects the presence or absence of information on the touch operation. On the other hand, when the main sensor 31 is plural, the coordinate detecting unit 42 also detects the user's touch position coordinate value.

The CPU 43 acquires the information output from the coordinate detecting unit 42 at regular intervals. And input to the display device 2 or the like based on the obtained information.

The drive line drive circuit 5 is connected to the drive line 35, and when the touch panel system 1 is activated, a potential is applied to the drive line 35 at a constant period.

(2) Noise processing of touch panel system 1

The touch panel system 1 detects the presence or absence of a touch operation based on a change in electrostatic capacitance detected by the touch panel controller 4. However, the touch panel 3 is followed by the front side (user side) of the display device 2. Therefore, the touch panel system 1 is not only affected by noises such as clocks generated by the display device 2, but also susceptible to other external noise. As a result, the detection sensitivity of the touch operation (detection sensitivity of the coordinate detecting unit 42) is lowered.

Therefore, as a countermeasure against such noise, the touch panel system 1 includes the sub sensor 32 and the subtraction unit 41. The noise cancellation processing of the touch panel system 1 will be described based on FIG. 2 is a flow chart showing the basic processing of the touch panel system 1, that is, the noise cancellation processing.

When the touch panel system 1 is activated, a potential is applied from the drive line drive circuit 5 to the drive line 35 at a certain period. When the user performs a touch operation on the touch panel 3, the two sensors of the main sensor 31 and the sub sensor 32 output signals to the subtraction unit 41.

Here, noise such as a clock generated by the display device 2 and other external noise are reflected on the touch panel 3. Therefore, the main sensor 31 and the sub sensor 32 detect various noise components. That is, the output signal of the autonomous sensor 31 adds a noise signal (noise component) to the original signal of the touch operation. On the other hand, the sub sensor 32 does not detect the touch operation. Therefore, the output signal from the sub-sensor 32 includes a noise signal (noise component), but does not include a touch operation. Signal (F201).

In the touch panel system 1, the main sensor 31 and the sub sensor 32 are disposed in the same plane and are disposed adjacent to each other. Therefore, 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 substantially the same value. Therefore, the subtraction unit 41 in the touch panel controller 4 performs a process of subtracting the input signal (signal value) of the sub sensor 32 from the input signal (signal value) of the main sensor 31 (F202). In other words, the subtraction unit 41 acquires the difference between the sensing line 33 and the sub sensing line 34. Thereby, the noise signal is removed from the output signal of the main sensor 31. Therefore, the original signal value of the touch operation generated by the touch operation is obtained.

The signal (the original signal of the touch operation) subjected to such subtraction processing is output to the coordinate detecting portion 42 (F203) existing in the touch panel controller 4. Thereby, the original signal of the touch operation is output to the coordinate detecting unit 42. The coordinate detecting unit 42 detects the presence or absence of the touch operation by the original signal processing of the touch operation. Therefore, it is possible to suppress the detection sensitivity of the coordinate detecting unit 42 (detecting the accuracy of the touch operation or the like) from falling.

As described above, in the touch panel system 1, the subtraction unit 41 obtains the difference between the sensing line 33 and the sub sensing line 34, and eliminates the noise component from the input signal from the sensing line 33 including a plurality of types of noise components. That is, the subtraction unit 41 removes the noise signal from the input signal of the sensing line 33, and extracts the original signal generated by the touch operation. Thus, a touch panel system 1 capable of reliably eliminating a plurality of types of noise can be provided.

On the other hand, if the noise cancellation processing of the touch panel system 1 is visually displayed, as shown in FIG. Figure 3 shows the reduction in the touch panel system 1 A diagram of the waveform of the signal processed by section 41. 3(a) shows the output signal of the main sensor 31, FIG. 3(b) shows the output signal of the sub sensor 32, and FIG. 3(c) shows the signal processed by the subtraction unit 41. Each of the signals shown in FIG. 3 is a signal when the user touches the operation.

In the touch panel system 1, if the user performs a touch operation, the capacitance of the main sensor 31 for detecting the touch operation is increased (FIG. 3(a)). That is, the output signal value of the autonomous sensor (induction line 33) is increased. However, in the output signal of the autonomous sensor 31 during the touch operation, not only the original signal of the touch operation but also various noises (such as the clock generated by the display device 2 and the external noise) are added. .

On the other hand, since the sub sensor 32 does not detect the touch operation, the capacitance of the sub sensor 32 (sub sense line) is not increased by the touch operation. That is, the output signal from the sub-sensor 32 does not include the touch operation signal, but includes the noise component reflected by the touch panel 3 (FIG. 3(b)).

The subtraction unit 41 subtracts the output signal from the sub-sensor 32 (the signal value of Fig. 3(a) - the signal value of Fig. 3(b)) from the output signal of the auto sensor 31. By this subtraction processing, as shown in FIG. 3(c), the noise component output from the sub sensor 32 is removed from the output signal of the auto sensor 31. Thereby, the original signal of the touch operation generated by the touch operation is obtained. Furthermore, since the original signal of the touch operation is input to the coordinate detecting unit 42, the detection accuracy of the touch operation is not lowered.

As described above, in the touch panel system 1 of the present embodiment, the main sensor 31 and the sub sensor 32 are disposed in the same plane (same surface) of the touch panel 3. Thereby, any one of the output signals from the main sensor 31 and the sub sensor 32 The number also includes various noise signals reflected on the touch panel 3. Furthermore, the subtraction unit 41 obtains the difference between the output signal of the autonomous sensor 31 including the signal of the touch operation and the noise signal, and the output signal of the slave sensor 32 including the noise signal. Thereby, 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 by the touch panel 3 can be surely removed (eliminated).

Further, in the touch panel system of Patent Document 1, the noise component to be removed includes the AC signal component in the signal of the noise component. In contrast, in the touch panel system 1, the output signals of the autonomous sensor 31 and the sub sensor 32 include various noise components. Therefore, the noise component to be removed as the touch panel system 1 is not limited to the AC signal component. Therefore, the touch panel system 1 can eliminate all the noise reflected by the touch panel 3.

In the touch panel system 1 , the sub sensor 32 may be provided in the same plane as the touch panel 3 together with the main sensor 31 . Thereby, both the main sensor 31 and the sub sensor 32 can detect the noise component (noise signal) reflected on the touch panel 3. However, the sub sensor 32 preferably does not detect the touch operation of the touch panel 3. According to this configuration, since the signal of the touch operation is not detected by the sub sensor 32, the signal of the touch operation is not included in the output signal of the sub sensor 32. Thereby, the subtraction processing by the subtraction unit 41 does not lower the signal value of the touch operation. That is, the touch operation signal detected by the main sensor 31 is not reduced, but the noise component is removed. Thereby, the detection sensitivity of the touch operation can be further improved.

For example, when the touch panel system 1 is used, the sub sensor 32 is disposed on the touch panel 3 (the non-touch area) where the user does not perform the touch operation. The signal is not detected by the secondary sensor 32. Therefore, the sub sensor 32 detects the noise reflected by the touch panel when the user does not touch the operation, but does not detect the touch operation signal. Thus, the secondary sensor 32 can surely avoid detecting touch operations.

When the noise component is detected by the sub sensor 32, the sub sensor 32 is preferably disposed in the vicinity of the main inductor 31 as much as possible, and is preferably disposed adjacent to the main inductor 31. Thereby, the main inductor 31 and the sub sensor 32 are arranged under substantially the same conditions. In particular, when the sub-sensor 32 is disposed adjacent to the main inductor 31, the main inductor 31 and the sub-sensor 32 are disposed closest to each other. Therefore, the noise signal value included in the output signal of the slave sensor 32 can be regarded as the same as the noise signal value included in the output signal of the autonomous sensor 31. Thereby, the noise component reflected by the touch panel 3 can be more reliably removed by the subtraction processing by the subtraction unit 41. Thereby, the detection sensitivity of the touch operation can be further improved.

In the present embodiment, the touch panel system 1 including the capacitive touch panel 3 will be described. However, the principle of operation of the touch panel 3 (the operation mode of the sensor) is not limited to the electrostatic capacitance method. For example, a touch panel system including a resistive film method, an infrared method, an ultrasonic method, or an electromagnetic induction coupling type touch panel system can also perform a noise canceling function. Further, the noise canceling function can be exerted regardless of the type of the display device 2.

The touch panel system 1 of the present embodiment can be applied to various electronic devices of the touch panel type. As the electronic device, a television, a computer, a mobile phone, a digital camera, an action game machine, an electronic photo frame, a mobile information terminal (PDA: Personal Digital Assistant, personal digital assistant), and an electronic device can be exemplified. Books, home appliances (microwave ovens, washing machines, etc.), ticket vending machines, ATM (Automated Teller Machine), and car navigation devices. Thereby, an electronic device capable of effectively suppressing a decrease in detection sensitivity of a touch operation can be provided.

[Embodiment 2]

(1) The composition of the touch panel system 1a

Fig. 4 is a schematic view showing the basic configuration of another touch panel system 1a of the present invention. The basic configuration of the touch panel system 1a is substantially the same as that of the touch panel system 1 of the first embodiment. Hereinafter, the touch panel system 1a will be described centering on the difference from the touch panel system 1. For the sake of convenience of explanation, members having the same functions as those of the drawings described in the first embodiment will be denoted by the same reference numerals and will not be described.

In the touch panel system 1a, the configuration of the sensor provided on the touch panel 3a is different from that of the touch panel system 1. That is, the touch panel 3a includes a main sensor group 31a including a plurality of main sensors 31, and a sub-sensor group 32a including a plurality of sub-sensors 32. The touch panel system 1a detects not only the user's touch operation but also the location information (coordinates) of the user's touch operation.

Specifically, in the touch panel system 1a, the touch panel 3a includes a main sensor group 31a and a sub sensor group 32a on the same surface (in the same plane) of the touch panel 3a. The main sensor group 31a and the sub sensor group 32a are disposed adjacent to each other. Each of the main sensor group 31a and the sub-sensor group 32a is constituted by a capacitive inductor.

The main sensor group (main sensing portion) 31a is disposed on the touch panel 3a to perform a touch operation area (touch area) for detecting the user to the touch panel 3a. Touch operation. The main sensor group 31a is composed of a plurality of main inductors 31 arranged in a lattice shape. The main sensor group 31a includes L (L is an integer of 2 or more) sensing lines 33. The sensing lines 33 are parallel to each other and are disposed at equal intervals. M (M is an integer of 2 or more) main inductor 31 is disposed on each of the sensing lines 33.

One end of each of the sensing lines 33 is connected to the subtraction unit 41 of the touch panel controller 4. Thereby, the signal detected by the main sensor 31 is output to the subtraction unit 41 via the respective sensing lines 33. That is, the 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 the noise component reflected by the touch panel 3a. The sub sensor group 32a is disposed in an area (non-touch area) on the touch panel 3a where no touch operation is performed. Therefore, the sub sensor group 32a is not touched by the user by the touch operation, and various noises generated by the touch panel system 1a are detected. Thereby, the sub sensor group 32a is different from the main sensor group 31a, and does not detect the signal corresponding to the touch operation. That is, the sub sensor group 32a is not touched by the user by the touch operation, and the noise generated by the sensor is detected. The secondary sensor group 32a includes a secondary sensing line 34. The secondary sensing line 34 is parallel to each of the sensing lines 33 (extending in the same direction as the sensing line 33). M (M is an integer of 2 or more) sub-sensors 32 are disposed on the sub-sensing line 34. That is, the number of the main inductors 31 disposed on the respective sensing lines 33 is the same as the number of the sub-sensors 32 disposed on the sub-sensing line 34.

One end of the sub sensing line 34 is connected to the subtraction unit 41 of the touch panel controller 4. Thereby, the signal detected by the sub sensor group 32a is output to the subtraction unit 41 via the sub sensing line 34.

On the other hand, the touch panel 3a includes M (M is an integer of 2 or more) driving lines 35, which intersects orthogonally to each of the sensing lines 33 and the sub sensing lines 34. The drive lines 35 are parallel to each other and are disposed at equal intervals. L (L is an integer of 2 or more) main inductor 31 and one sub sensor 32 are arranged on each drive line 35. Further, an electrostatic capacitance is formed at an intersection of each of the sensing lines 33 or the sub sensing lines 34 and the respective driving lines 35. That is, a capacitance is formed between each of the sensing lines 33 and each of the driving lines 35 and between the sub sensing lines 34 and the respective driving lines 35. The drive line 35 is connected to a drive line drive circuit (not shown), and when the touch panel system 1a is activated, a potential is applied to the drive line 35 at a predetermined period.

Thereby, in the touch panel 3a, the sensing line 33 and the sub sensing line 34 provided in the lateral direction and the driving line 35 provided in the longitudinal direction are arranged in a two-dimensional matrix. The number, length, width, and interval of the sensing line 33, the sub sensing line 34, and the driving line 35 can be arbitrarily set according to the use of the touch panel system 1a or the size of the touch panel 3a.

(2) Noise processing of touch panel system 1a

The touch panel system 1a detects the presence or absence of a touch operation and a touch position based on a change in electrostatic capacitance detected by the touch panel controller 4. However, the touch panel system 1a is also the same as the touch panel system 1, and is susceptible to various noises. As a result, the detection sensitivity of the touch operation (detection sensitivity of the coordinate detecting portion) is lowered. Specifically, FIG. 5 is a schematic view showing the touch panel 3b of the touch panel system 1a of FIG. 4 without the sub sensor group 32a. As shown in FIG. 5, 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 is configured before the noise countermeasure. In this case, the touch panel 3b is affected by various noises. Therefore, the signals output from the sensing lines 33 include various noise components to make the touch operation The detection sensitivity is reduced.

Therefore, as a measure for removing such noise, the touch panel system 1a includes the sub sensor group 32a and the subtraction unit 41. The noise canceling processing of the touch panel system 1a will be described based on FIG. FIG. 6 is a flow chart showing the noise canceling process of the basic processing of the touch panel system 1a.

When the touch panel system 1a is activated, a potential is applied to the drive line 35 at a certain period. When the touch operation is performed on the touch panel 3a, the two sensor groups of the main sensor group 31a and the sub sensor group 32a output signals to the subtraction unit 41. Specifically, if the user performs a touch operation, the capacitance of the specific main sensor 31 corresponding to the touch position increases. That is, the output signal value from the main inductor 31 (sensing line 33) is increased. The touch panel system 1a outputs the output signals from the induction line 33 and the sub-sensing line 34 to the subtraction unit 41 while driving the drive lines 35.

More specifically, noise such as a clock generated by the display device 2 and other external noise are reflected on the touch panel 3a. Therefore, various noise components are detected in the main sensor group 31a and the sub sensor group 32a. That is, the output signal from the main sensor group 31a adds a noise signal (noise component) to the original signal of the touch operation. On the other hand, the sub sensor group 32a does not detect the touch operation. Therefore, although the noise signal (noise component) is included in the output signal of the sub sensor group 32a, the signal of the touch operation (F501) is not included.

In the touch panel system 1a, the main sensor group 31a and the sub sensor group 32a are disposed in the same plane, and are disposed adjacent to each other. Therefore, the noise signal value included in the output signal of the main sensor group 31a and the noise signal value of the output signal of the sub sensor group 32a can be regarded as substantially the same value. therefore, The subtraction unit 41 existing in the touch panel controller 4 performs a process of subtracting the input signal (signal value) from the sub sensor group 32a from the input signal (signal value) of the auto sensor group 31a (F502). That is, the subtraction unit 41 extracts the difference between each of the sensing lines 33 and the sub sensing lines 34. Thereby, the noise signal is removed from the output signal of the autonomous sensor group 31a. Thereby, the original signal value of the touch operation generated by the touch operation is obtained.

The signal subjected to such subtraction processing is output to the coordinate detecting portion 42 (F503) existing in the touch panel controller 4. Thereby, the original signal of the touch operation is output to the coordinate detecting unit 42. The coordinate detecting unit 42 detects the presence or absence of the touch operation and the touch position (coordinate) by the original signal processing of the touch operation. Therefore, it is possible to suppress a decrease in the detection sensitivity of the coordinate detecting unit 42 (the detection accuracy of the touch operation or the detection sensitivity of the touch position, etc.).

In addition, in the touch panel system 1a, the output signal from the sensing line 33 including the specific main sensor 31 corresponding to the touch position has a waveform as shown in FIG. 3(a), and is from the sub-sensor group 32a (sub The signal output from the sensing line 34) has the waveform shown in Figure 3(b). The subtraction unit 41 subtracts the output signal from the sub-sensor group 32 from the output signal of the autonomous sensor group 31a. By this subtraction processing, as shown in FIG. 3(c), the noise component output from the sub-sensor group 32a is removed from the output signal of the autonomous sensor group 31a. Thereby, the original signal of the touch operation generated by the touch operation is obtained. Furthermore, since the original signal of the touch operation is input to the coordinate detecting unit 42, the detection accuracy of the touch operation and the detection accuracy of the touch position are not lowered. Therefore, the deviation between the actual touch position and the detected position detected by the coordinate detecting unit 42 can be reduced.

As described above, the touch panel system 1a drives the drive line 35 while driving The change in the capacitance value of the main sensor group 31a caused by the touch operation by the user is read by the sensing line 33. Further, the noise component is read from the sub sensing line 34. Further, in the subtraction unit 41, the difference between the sensing line 33 and the sub sensing line 34 can be obtained, and the noise component can be removed (eliminated).

The main sensor group 31a of the touch panel system 1a is composed of a plurality of main inductors 31 arranged in a matrix in the longitudinal direction and the lateral direction. Thereby, in addition to the same effect as the touch panel 1, the coordinate detecting unit 42 can detect the touched coordinates. That is, the presence or absence of the touch operation can be detected, and the touch position (coordinate value) can be detected.

Similarly to the touch panel system 1, in the touch panel system 1a, the noise component to be removed is not limited to the AC signal component. Therefore, the touch panel system 1a can also eliminate all the noise reflected by the touch panel 3a.

[Embodiment 3]

(1) The composition of the touch panel system 1b

Fig. 7 is a schematic view showing the basic configuration of another touch panel system 1b of the present invention. The basic configuration of the touch panel system 1b is substantially the same as that of the touch panel system 1a of the second embodiment. Hereinafter, the touch panel system 1b will be described centering on the difference from the touch panel system 1a. For the sake of convenience of explanation, members having the same functions as those of the drawings described in the first and second embodiments are denoted by the same reference numerals and will not be described.

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 includes: a plurality of (five in FIG. 7) driving lines 35; a plurality of (seven in FIG. 7) sensing lines 33, which intersect with each driving line 35; and one pair Inductive line 34, which is orthogonal to each drive line 35, and parallel to the sensing line 33. The sensing line 33 and the driving line 35, and the sub sensing line 34 and the driving line 35 are insulated from each other and capacitively coupled.

Hereinafter, eight inductive/secondary sensing line arrays including one sub sensing line 34 and seven sensing lines 33 will be described as an arrangement (1) to an array (8).

The touch panel controller 4 includes, in order from the input side, a switch SW, a subtraction unit 41, storage units 45a to 45d, and an addition unit 46. Although not shown, the touch panel controller 4 also includes a coordinate detecting unit 42 and a CPU 43 (FIG. 1). Thereby, the touch panel controller 4 of the touch panel system 1b is configured differently from the touch panel systems 1, 1a.

The switch SW switches the signal input from the sensing line 33 or the sub sensing line 34 to the subtraction unit 41. In more detail, the switch SW includes two upper and lower terminals, and one of the terminals is selected. Fig. 7 shows the state in which the switch SW selects the lower terminal.

The subtraction unit 41 performs differential signal processing of the signals of the arrays (1) to (8) selected by the switch SW. In other words, the subtraction unit 41 performs differential signal processing between the adjacent sensing lines 33 and differential signal processing between the adjacent sensing lines 33 and the sub sensing lines 34. For example, as shown in FIG. 7, when the switch SW selects the lower terminal, the subtraction unit 41 performs arrangement (8)-arrangement (7), arrangement (6)-arrangement (5), arrangement (4)-arrangement (3). ), and arrange the differential signal processing of (2)-arrangement (1). On the other hand, although not shown, when the switch SW selects the upper terminal, the subtraction unit 41 performs arrangement (7)-arrangement (6), arrangement (5)-arrangement (4), and arrangement (3)- Arrange the differential signal processing of (2).

The storage units 45a to 45d store signals (differential processing signals) that are subjected to differential processing by the subtraction unit 41 when the switch SW selects one terminal. Stored in storage The differential processing signals of 45a to 45d are output to the addition unit 46. Further, when the switch SW selects the other terminal, the differential processing signal is directly output to the addition unit 46 without passing through the storage units 45a to 45d.

The adding unit 46 adds the difference processing signals of the adjacent sensing lines 33 input from the subtracting unit 41 and the storage units 45a to 45d, and outputs the added processing result. Further, the adding unit 46 outputs a difference processing signal (arrangement (2)-arrangement (1)) stored in the sub sensing line 34 of the storage unit 45a and the sensing line 33 adjacent thereto. The adding unit 46 finally outputs the arrangement (2) - arrangement (1), arrangement (3) - arrangement (1), arrangement (4) - arrangement (1), arrangement (5) - arrangement (1), arrangement (6) - Arrange the signals of (1), Arrange (7) - Arrange (1), Arrange (8) Arrange (1). That is, the signal output from the adding unit 46 has removed the noise signal (the signal of the array (1)) included in the sensing line 33. Further, the subtraction unit 41 performs differential signal processing between the adjacent sensing lines 33. Therefore, the self-addition unit 46 outputs a signal that more surely removes the noise signal.

(2) Noise processing of touch panel system 1b

The noise processing of the touch panel system 1b will be described based on FIGS. 7 and 8. FIG. 8 is a flow chart showing the basic processing of the touch panel system 1b, that is, the noise canceling processing.

When the touch panel system 1b is activated, a potential is applied to the drive line 35 at a specific cycle. When the user performs a touch operation on the touch panel 3b, the capacitance of the specific sensing line 33 corresponding to the touch position increases. That is, the signal value output from the sensing line 33 is increased. The touch panel system 1b outputs the output signals of the self-sensing line 33 and the sub-sensing line 34 to the touch panel controller 4 while driving the respective driving lines 35. Thereby, the touch panel system 1b drives the driving line on one side 35, detecting the change of the capacitance of the sensing line 33 and the sub sensing line 34, and detecting the presence or absence of the touch operation and the touch position.

More specifically, noise such as a clock generated by the display device 2 and other external noise are reflected in the touch panel 3b. Therefore, various noise components are detected in the main sensor group 31a and the sub sensor group 32a. That is, the output signal of the self-sensing line 33 is added to the original signal of the touch operation to add a noise signal (noise component). On the other hand, the secondary sensing line 34 does not detect the touch operation. Therefore, although the output signal from the auxiliary sensing line 34 includes a noise component (noise component), it does not include a touch operation signal (F601).

Next, the switch SW selects the lower terminal (F602). Next, the subtraction unit 41 obtains a difference between the sensing line 33 (induction line Sn) and the sensing line (induction line Sn+1) adjacent to the sub sensing line 34 of the two sensing lines 33 adjacent to the sensing line 33 (induction) Line (Sn+1)-Sn: first difference). At this time, the sensing line 33 closest to the sub sensing line 34 acquires a difference (third difference) from the sub sensing line 34 (F603).

In the arrangement (1) to (8) of Fig. 7, the subtraction unit 41 performs

. Arrange (2) - Arrange (1) (take the difference value as A)

. Arrange (4) - Arrange (3) (take the difference value as C)

. Arrange (6)-arrange (5) (take the difference value as E)

. Four kinds of differential signals are processed by (8)-arrangement (7) (the difference value is referred to as G). That is, in step F603, the differential signal processing including the arrays (1) to (8) of the sub sensing lines 34 is performed.

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. Score G (F604).

Then, the switch SW that selects the lower terminal is switched to select the upper terminal (closed) (F605). Next, the subtraction unit 41 performs the same processing as F603. That is, differential signal processing (inductive line) between the sensing line 33 (sensing line Sn) and the sensing line (sensing line Sn-1) away from the sub sensing line 34 of the two sensing lines 33 adjacent to the sensing line 33 is performed. Sn-(Sn-1): second difference) (F606).

In the arrangement (1) to (8) of Fig. 7, the subtraction unit 41 performs

. Arrange (3) - Arrange (2) (take the difference value as B)

. Arrange (5) - Arrange (4) (take the difference value as D)

. Three kinds of differential signals are processed (7)-arranged (6) (the difference value is taken as F). That is, in step F606, the differential signal processing in which the arrays (2) to (7) of the sub sensing line 34 are not included is performed.

Next, the adding unit 45 performs the 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. In other words, the difference value (difference values A, C, E, G) in the case where the lower terminal is selected for the switch SW and the difference value (difference value B, D, F) in the case where the upper terminal is selected are added (F607).

In the arrangement (1) to (8) of Fig. 7, the adding unit 46 first compares the difference value A (arrangement (2) - arrangement (1) signal) stored in the storage unit 45a and the difference value B output from the self-subtraction unit 41. (Arrange (3) - Arrange (2) signals) for addition. This addition processing is a difference value A + difference value B = {arrangement (2) - permutation (1)} + {arrangement (3) - permutation (2)} = permutation (3) - permutation (1) (the difference value As the difference value H), the signal of the arrangement (3)-arrangement (1) can be obtained. The adding unit 46 performs such processing in order.

That is, the difference value H (the signal of the arrangement (3)-arrangement (1)) is added and stored in The difference value C of the storage unit 45b (the signal of the arrangement (4) - arrangement (3)). As a result, the signal of the arrangement (4)-arrangement (1) (difference value I) can be obtained.

Then, the difference value I (the signal of the array (4) - array (1)) is added to the difference value D (the signal of the array (5) - array (4)) output from the subtraction unit 41. As a result, the signal of the arrangement (5)-arrangement (1) (difference value J) can be obtained.

Next, the difference value J (the signal of the array (5) - array (1)) is added to the difference value E (the signal of the array (6) - array (5)) stored in the storage portion 45c. As a result, the signal of the arrangement (6)-arrangement (1) (difference value K) can be obtained.

Next, the difference value K (the signal of the array (6)-arrangement (1)) is added to the difference value F (the signal of the array (7) - array (6)) output from the subtraction unit 41. As a result, the signal (difference value L) of the array (7)-arrangement (1) can be obtained.

Next, the difference value L (the signal of the array (7) - array (1)) is added to the difference value G (the signal of the array (8) - array (7)) stored in the storage portion 45d. As a result, the signal (differential value M) of the array (8)-arrangement (1) can be obtained.

Further, the difference value A stored in the storage unit 45a (that is, the signal of the arrangement (2)-arrangement (1)) is directly outputted without addition processing by the addition unit 46.

Thus, the self-addition unit 46 outputs the following signals:

. Arrangement (2) - Arrangement (1) Signal = Differential Value A

. Arrangement (3) - Arrangement (1) Signal = Differential Value H

. Arrangement (4) - Arrangement (1) Signal = Differential Value I

. Arrangement (5) - Arrangement (1) Signal = Differential Value J

. Arrangement (6) - Arrangement (1) Signal = Differential Value K

. Arrangement (7)-arrangement (1) signal = differential value L

. Arrange (8) - Arrange (1) Signal = Differential Value M.

In Fig. 7, the array (2) to the array (8) are the sensing lines 33, and the array (1) is the sub sensing line 34. The result of the addition processing by the adding unit 46 removes the signal (noise signal) of the array (1) from the signals of the arrays (2) to (8). Therefore, the output signal of the self-addition unit 46 becomes the noise signal included in the signal from which the sensing line 33 has been removed, and the original signal value of the touch operation generated by the touch operation is obtained. The output signal of the self-addition unit 46 from which the noise signal has been removed is output to the coordinate detecting unit 42 in the touch panel controller 4. That is, the original signal of the touch operation is output to the coordinate detecting unit 42 (F608).

As described above, the touch panel system 1b obtains a differential signal value between adjacent sensing lines 33. That is, the difference between the adjacent sensing lines 33 with higher noise correlation is obtained. Furthermore, the signal (noise signal) of the secondary sensing line 34 is also removed from the output signal of each sensing line 33. Therefore, the touch panel system 1b can more reliably remove noise than the touch panel systems 1 and 1a of the first and second embodiments.

In addition, the addition processing of the addition unit 46 is performed sequentially from the side of the sub-sensing line 34 (sequentially from the sub-sensing line 34), and the addition processing result can be used for the subsequent addition processing while performing the addition processing. Remove noise.

[Embodiment 4]

Although the driving method of the touch panel system of the present invention is not particularly limited, it is preferably an orthogonal sequence driving method. In other words, it is preferable to drive the drive line 35 in parallel. FIG. 9 is a view showing a driving manner of a touch panel in a previous touch panel system. FIG. 10 is a view showing a driving method (orthogonal sequence driving method) of a touch panel in the touch panel system of the present invention.

FIG. 9 shows a case where four sensors are present on one sensing line drawn from the touch panel. As shown in Figure 9, the previous touch panel system is driven by the driver. At the time of the line, +V volts is applied to the driving line of the driving, and the driving line is driven successively.

Specifically, the first drive of the drive line applies +V volts to the leftmost sensor. Thereby, the first measurement result (X1) of Vout is X1=C1×V/Cint.

Similarly, the second drive of the drive line applies +V volts to the second sensor from the left. Thereby, the second measurement result (X2) of Vout is X2=C2×V/Cint.

The third drive of the drive line applies +V volts to the third sensor from the left. Thereby, the third measurement result (X3) of Vout is X3=C3×V/Cint.

The fourth drive of the drive line applies +V volts to the rightmost sensor. Thereby, the fourth measurement result (X4) of Vout is X4=C4×V/Cint.

In this regard, FIG. 10 is also the same as FIG. 9 and shows that there are four sensors on one sensing line drawn from the touch panel. As shown in FIG. 10, in the case of the orthogonal sequence driving method, when the driving line is driven, +V volts or -V volts is applied to all of the driving lines. That is, in the orthogonal sequence driving method, the driving lines are driven in parallel.

Specifically, the first drive of the drive line applies +V volts to all of the inductors. Thereby, the first measurement result (Y1) of Vout is Y1=(C1+C2+C3+C4)×V/Cint.

The second drive of the drive line applies +V volts to the leftmost sensor, and -V volts to the second sensor from the left, and +V volts Apply to the third sensor from the left and apply -V volts to the rightmost sensor. Thereby, the second measurement result (Y2) of Vout is Y2=(C1-C2+C3-C4)×V/Cint.

The third drive of the drive line applies +V volts to the leftmost sensor, +V volts to the second sensor from the left, and -V volts to the third sensor from the left Up and apply -V volts to the rightmost sensor. Thereby, the third measurement result (Y3) of Vout is Y3=(C1+C2-C3-C4)×V/Cint.

The fourth drive of the drive line applies +V volts to the leftmost sensor, -V volts to the second sensor from the left, and -V volts to the third sensor from the left Up and apply +V volts to the rightmost sensor. Thereby, the fourth measurement result (Y4) of Vout is Y4=(C1-C2-C3+C4)×V/Cint.

In Fig. 10, the values of the capacitance values (C1, C2, C3, C4) can be obtained by the inner product of the output sequence (Y1, Y2, Y3, Y4) and the orthogonal code di. This formula is established due to the orthogonality of the orthogonal codes di. Here, the code di shows the positive and negative voltage codes applied to the respective drive lines. That is, the code d1 is a voltage code applied to the leftmost sensor, that is, "+1, +1, +1, +1". The code d2 is a voltage code applied to the second sensor from the left, that is, "+1, -1, +1, -1". The code d3 is a voltage code applied to the third sensor from the left, that is, "+1, +1, -1, -1". The code d4 is a voltage code applied to the rightmost sensor, that is, "+1, -1, -1, +1".

If the values of C1, C2, C3, and C4 are obtained by the inner product of the output sequences Y1, Y2, Y3, and Y4 and the codes d1, d2, d3, and d4, then C1=1×Y1+1×Y2+1×Y3+1×Y4=4C1×V/Cint

C2=1×Y1+(-1)×Y2+1×Y3+(-1)×Y4=4C2×V/Cint

C3=1×Y1+1×Y2+(-1)×Y3+(-1)×Y4=4C3×V/Cint

C4 = 1 × Y1 + (-1) × Y2 + (-1) × Y3 + (-1) × Y4 = 4C3 × V / Cint.

Thus, Ci is obtained by the inner product of the code di and the output sequence Yi by the orthogonality of the code di. If the result is compared with the previous driving mode shown in FIG. 9, a value of 4 times can be detected in the same number of driving times. FIG. 11 is a view showing a process necessary for obtaining the same sensitivity as the touch panel of the driving method of FIG. 10 using the touch panel of the driving method of FIG. 9. As shown in Fig. 11, in order to obtain the same sensitivity as the driving method of Fig. 10 by the driving method of Fig. 9, it is necessary to repeat the driving of the same driving line four times, and to add these results. That is, the driving time of the driving line is four times. Conversely, with the driving method shown in FIG. 10, in order to obtain the same sensitivity as the previous driving method shown in FIG. 9, the driving time of the driving line is shortened to 1/4 of that in the driving mode shown in FIG. Thereby, the power consumption of the touch panel system can be reduced.

FIG. 12 is a schematic view showing a touch panel system 1c including the touch panel 3 of such an orthogonal sequence driving method. That is, the touch panel system 1c of FIG. 12 generally displays four drive lines and one sense line as shown in FIG.

Specifically, the touch panel system 1c is formed with a matrix capacitance between the M drive lines 35 and the L sense lines 33 (both M and L are natural numbers). In the touch panel system 1c, for the electrostatic capacitance matrices Cij (i = 1, ... M, j = 1, ..., L), code lengths orthogonal to each other composed of +1 and -1 are used. The code of N is di=(di1,...,diN)(i=1,...,M), which becomes +V volt when +1, -1 When the mode becomes -V volts, all the M drive lines 35 are driven in parallel. Then, the output sequence sj=(sj1, . . . , sjN) (j=1, . . . , L) read by each sensing line 33 and the inner product of the code di operate di. Sj=Σ(k=1,...,N)dik. Sjk, to estimate the capacitance value Cij. The touch panel system 1c is provided with a charge integrator 47 (decoding unit) for performing such inner product calculation. The signal strength of the output signal (Vout) from the charge integrator 47 is obtained by Vout = Cf × Vdrive × N / Cint.

The output sequence sj is sj=(sj1,...,sjN)=(Σ(k=1,...,M)Ckj×dk1,...,Σ(k=1,...,M)Ckj ×dkN)×(Vdrive/Cint)=(Σ(k=1,...,M)Ckj×(dk1,...,dkN)×(Vdrive/Cint)=Σ(k=1,... , M) (Ckj × dk) × (Vdrive / Cint).

The code di is integrated with the output sequence sj. Sj=di. (Σ(k=1,...,M)(Ckj×dk)×(Vdrive/Cint))=Σ(k=1,...,M)(Ckj×di.dk)×(Vdrive/Cint )=Σ(k=1,...,M)(Ckj×N×δik)×(Vdrive/Cint)[if i=k then δik=1, if i is not 1, then δik=0]=Cij× N × (Vdrive / Cint).

Thus, according to the touch panel system 1c, the touch panel 3 is driven by the orthogonal sequence driving method. Therefore, by calculating the inner product of the code di and the output sequence sj, a capacitance Cij signal of N (code length) times is generally obtained. The effect of the driving method does not depend on the number M of the driving lines 35, and the signal intensity of the capacitor is multiplied by N. In addition, in other words, by using orthogonal sequence driving, The sensitivity equal to that of the previous driving method shown in FIG. 9 is obtained, and the driving time of the driving line can be shortened to 1/N in the driving mode shown in FIG. That is, the number of driving of the drive line can be reduced. Thereby, the power consumption of the touch panel system 1c can be reduced.

[Embodiment 5]

Fig. 13 is a schematic view showing the basic configuration of the touch panel system 1d of the embodiment. The touch panel system 1d applies the orthogonal sequence driving method of the driving line 35 in the touch panel system 1c shown in FIG. 10 and FIG. 12 for the touch panel system 1b with the noise canceling function as shown in FIG. By. Since the operation of the touch panel system 1d is the same as that of the above-described touch panel systems 1b and 1c, description thereof will be omitted.

According to the touch panel system 1d, the difference signal value between the adjacent sensing lines 33 is obtained. That is, the difference between the adjacent sensing lines 33 with higher noise correlation is obtained. Furthermore, the signal (noise signal) of the sub-sensing line 34 is removed from the output signal of each sensing 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. Further, since the capacitance Cij signal of N (code length) is obtained, the number of the drive lines 35 is not dependent, and the signal strength of the capacitor is multiplied by N. Further, by using the orthogonal sequence driving method, in order to obtain the same sensitivity as the previous driving method shown in FIG. 9, the driving time of the driving line is shortened to 1/N in the driving mode shown in FIG. That is, the number of driving of the drive line can be reduced. Thereby, the power consumption of the touch panel system 1d can be reduced.

[Embodiment 6]

Figure 14 is a view showing the basic configuration of the touch panel system 1e of the present embodiment. Schematic diagram. In the touch panel system 1e, the configuration of the subtraction unit 41 is different.

The output signals of the self-sensing line 33 and the sub-sensing line 34 of the touch panel 3b are analog signals. Therefore, the subtraction unit 41 includes an AD conversion unit 48 (third AD conversion unit) and a digital subtractor (not shown).

Thereby, 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 the same subtraction processing as the touch panel system 1b of FIG. 7 using the converted digital signal.

In this manner, the touch panel system 1e converts the analog signal output from the touch panel 3b into a digital signal, and then performs noise reduction to eliminate noise.

[Embodiment 7]

Fig. 15 is a schematic view showing the basic configuration of the touch panel system 1f of the embodiment. In the touch panel system 1f, the configuration of the subtraction unit 41 is different.

The output signals of the self-sensing line 33 and the sub-sensing line 34 of the touch panel 3b are analog signals. Therefore, the subtraction unit 41 includes the differential amplifier 49 and the AD conversion unit 48.

Thereby, the differential amplifier 49 directly performs the same subtraction processing as the touch panel system 1b of FIG. 7 by the analog signal from the output signal (analog signal) of the touch panel 3b. The AD conversion unit 48 (fourth AD conversion unit) converts the analog signal after the subtraction process into a digital signal.

In this way, the touch panel system 1f directly subtracts the analog signal outputted from the touch panel 3b with the analog signal, and then converts it into a digital signal, thereby removing the noise.

[Embodiment 8]

Fig. 16 is a schematic view showing the basic configuration of the touch panel system 1g of the embodiment. In the touch panel system 1g, the configuration of the subtraction unit 41 is different. The touch panel system 1g includes a fully differential amplifier 50 instead of the differential amplifier 49 of the touch panel system 1f of FIG.

The output signals of the self-sensing line 33 and the sub-sensing line 34 of the touch panel 3b are analog signals. Therefore, the subtraction unit 41 includes the fully differential amplifier 50 and the AD conversion unit 48.

Thereby, the full differential amplifier 50 directly performs the same subtraction processing as the touch panel system 1b of FIG. 7 by the analog signal from the output signal (analog signal) of the touch panel 3b. The AD conversion unit 48 converts the analog signal after the subtraction process into a digital signal.

Fig. 17 is a circuit diagram showing an example of the fully differential amplifier 50. The fully differential amplifier 50 is symmetrically arranged with two pairs of electrostatic capacitors and switches in the differential amplifier. Specifically, a signal from the adjacent sensing line 33 is input to the non-inverting input terminal (+) and the inverting input terminal (-). The same connection is made between the inverting output terminal (-) of the differential amplifier and the non-inverting input terminal (+), and between the non-inverting output terminal (+) and the inverting input terminal (-) of the differential amplifier. Capacitor (feedback capacitor). Further, a switch is connected between the inverting output terminal (-) and the non-inverting input terminal (+) and between the non-inverting output terminal (+) and the inverting input terminal (-).

In this way, the touch panel system 1g can directly reduce the analog signal outputted from the touch panel 3b by analog signals, and then convert the digital signals into digital signals to remove the noise.

[Embodiment 9]

Fig. 18 is a schematic view showing the basic configuration of the touch panel system 1h of the embodiment. In the touch panel system 1h, the configuration of the subtraction unit 41 and the driving method of the touch panel 3b are different. The touch panel system 1h includes a fully differential amplifier 50 in place of the differential amplifier 49 of the touch panel system 1f of FIG.

The output signals of the self-sensing line 33 and the sub-sensing line 34 of the touch panel 3b are analog signals. Therefore, the subtraction unit 41 includes the fully differential amplifier 50 and the AD conversion unit 48.

Thereby, the full differential amplifier 50 directly performs the same subtraction processing as the touch panel system 1b of FIG. 7 by the analog signal from the output signal (analog signal) of the touch panel 3b. The AD conversion unit 48 converts the analog signal after the subtraction process into a digital signal.

Further, in the touch panel system 1h, as the driving method of the touch panel 3b, the orthogonal sequence driving method shown in FIGS. 10, 12, and 13 is used. In this case, as shown in FIG. 10, the voltages of the four driving lines are driven, and in the case of the second to fourth times, the number of times +V is applied is the same as the number of times -V is applied twice, as opposed to Thus, in the first case, +V was applied 4 times. Therefore, the output value of the first output sequence Y1 becomes larger than the output value of the output sequences Y2 to Y4 of the second to fourth times. Therefore, if the output values of the output sequences Y2 to Y4 of the second to fourth times match the dynamic range, the output sequence Y1 of the first time is saturated.

Therefore, the subtraction unit 41 of the touch panel system 1h includes the fully differential amplifier 50. Furthermore, the fully differential amplifier 50 employs an input common mode voltage range for rail-to-rail actor. That is, the full differential amplifier 50 has a wide common mode input range. Thereby, the fully differential amplifier 50 can be connected to the power supply voltage (Vdd) to GND. Operates within the voltage range. And the difference between the input signals input to the fully differential amplifier 50 is amplified. Therefore, regardless of the combination of the orthogonal sequence driving method of the touch panel 3b, the output signal from the fully differential amplifier 50 does not cause an output saturation problem. In addition, an example of the fully differential amplifier 50 is as shown in FIG. 17 described above.

In this way, the touch panel system 1h can directly reduce the analog signal outputted from the touch panel 3b by analog signals, convert the digital signals into digital signals, and remove the noise. Furthermore, since the fully differential amplifier 50, which can perform a rail-to-rail operation, does not cause an output saturation problem from the output signal of the fully differential amplifier 50.

[Embodiment 10]

In the first to ninth embodiments, the touch panel system including the sub sensor 32 (the sub sensor line 34) will be described. However, in the touch panel system of the present invention, the sub sensor 32 is not necessarily configured. This embodiment describes a touch panel system that does not include the sub sensor 32.

Fig. 20 is a schematic view showing the basic configuration of the touch panel system 1i of the embodiment. The touch panel system 1i includes a subtraction unit 41a for calculating differential signals of the sensing lines 33 adjacent to each other.

More specifically, the touch panel 3c includes a plurality of (five in FIG. 20) driving lines 35 and a plurality of (eight in FIG. 20) sensing lines 33 crossing the respective driving lines 35. The sensing line 33 and the driving line 35 are insulated from each other and capacitively coupled.

The touch panel controller 4 includes, from the input side, a switch SW, a subtraction unit 41a, and storage units 45a to 45d. Further, although not shown, the touch panel controller 4 also includes a coordinate detecting unit 42 and a CPU 43 (see FIG. 1).

The subtraction unit 41a includes an input terminal (an input terminal for main inductor output) for receiving a signal output from the autonomous sensor 31. The subtraction unit 41a receives the signal of the autonomous sensor 31, and subtracts the signals of the sensing lines 33 adjacent to each other, and calculates a difference value (differential signal). The signal subtracted by the subtraction unit 41a is output to the coordinate detecting unit 42 (see Fig. 1).

As described above, the touch panel system 1i differs in that the sub sensor 32 (sub sensor line 34) is not included, and the processing of the subtraction unit 41a is different from that of the touch panel system of the above embodiment.

The switch SW switches the signal input from the sensing line 33 to the subtraction unit 41a. In more detail, the switch SW includes two upper and lower terminals, and one of the terminals is selected. Fig. 20 shows a state in which the switch SW selects 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. In other words, the subtraction unit 41a performs differential signal processing between the adjacent sensing lines 33. For example, as shown in FIG. 20, in the case where the switch SW selects the lower terminal, the subtraction unit 41a performs arrangement (8)-arrangement (7), arrangement (6)-arrangement (5), arrangement (4)-arrangement (3). And sorting (2)-arrangement (1) for each differential signal processing. On the other hand, although not shown, in the case where the switch SW selects the upper terminal, the subtraction unit 41a performs the arrangement of (7)-arrangement (6), arrangement (5)-arrangement (4), and arrangement (3)-arrangement. (2) Each differential signal processing.

The storage units 45a to 45d store signals (differential processing signals) subjected to the difference processing by the subtraction unit 41a when the switch SW selects one terminal. Further, when the switch SW selects the other terminal, the differential processing signal is directly outputted without passing through the storage sections 45a to 45d.

(2) Noise processing of touch panel system 1i

The noise processing of the touch panel system 1i will be described based on FIGS. 20 and 21. 21 is a flow chart showing the basic processing of the touch panel system 1i, that is, the noise canceling processing.

When the touch panel system 1i is activated, a potential is applied to the drive line 35 at a specific cycle. When the user performs a touch operation on the touch panel 3c, the capacitance of the specific sensing line 33 corresponding to the touch position changes. That is, the output signal value from the sensing line 33 changes. The touch panel system 1i outputs the output signals of the self-sensing line 33 to the touch panel controller 4 while driving the respective driving lines 35. Thereby, the touch panel system 1i detects the change in the capacitance of the sensing line 33 while driving the driving line 35, and detects the presence or absence of the touch operation and the touch position.

More specifically, noise such as a clock generated by the display device 2 and other external noise are reflected on the touch panel 3c. Therefore, various noise components are detected in the main sensor group 31b. That is, the output signal of the self-sensing line 33 adds a noise signal (noise component) to the original signal of the touch operation (F701). Then, the switch SW selects the lower terminal (F702). Next, the subtraction unit 41a obtains a difference between the sensing line 33 (sensing line Sn) and one of the two sensing lines 33 adjacent to the sensing line 33 (sensing line Sn+1) (sensing line (Sn+1) )-Sn: first difference) (F703).

In the arrangement (1) to (8) of Fig. 20, the subtraction unit 41a performs

. Arrange (2) - Arrange (1) (take the difference value as A)

. Arrange (4) - Arrange (3) (take the difference value as C)

. Arrange (6)-arrange (5) (take the difference value as E)

. Four kinds of differential signals at the (8)-arrangement (7) (the difference value is taken as G) Reason. That is, in step F703, the differential signal processing of the arrays (1) to (8) of the sensing lines 33 is performed.

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).

Then, the switch SW that selects the lower terminal is switched to select the upper terminal (closed) (F705). Next, in the subtraction unit 41a, the same processing as F703 is performed. That is, the differential signal processing between the sensing line 33 (inductive line Sn) and the other of the two sensing lines 33 adjacent to the sensing line 33 (sensing line Sn-1) is performed ((sensing line Sn-(Sn) -1)): 2nd difference) (F706).

In the arrangement (1) to (8) of Fig. 20, the subtraction unit 41a performs

. Arrange (3) - Arrange (2) (take the difference value as B)

. Arrange (5) - Arrange (4) (take the difference value as D)

. Three kinds of differential signals are processed (7)-arranged (6) (the difference value is taken as F). That is, in step F706, the differential signal processing of the arrays (2) to (7) is performed.

As described above, the touch panel system 1i obtains the difference signal value between the adjacent sensing lines 33. That is, the difference between the adjacent sensing lines 33 with 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, it is possible to more reliably remove (eliminate) various types of noise reflected by the touch panel 3c.

[Embodiment 11]

Figure 22 is a diagram showing the basic configuration of the touch panel system 1j of the present embodiment. Schematic diagram. The touch panel system 1j applies a drive line drive circuit (not shown) that drives the drive line 35 in parallel with the touch panel system 1i with the noise canceling function shown in FIG. 20 described above. Further, the touch panel system 1j includes a decoding unit 58 that decodes a difference value of the capacitance calculated by the subtraction unit 41a, and a non-touch operation information storage unit 61 that is stored in the non-touch operation by the decoding unit. a differential distribution of the decoded electrostatic capacitances; and a correction unit 62 that corrects a differential distribution of the electrostatic capacitances decoded by the decoding unit 58 during the touch operation. Since the operation of the touch panel system 1j is the same as that of the above-described touch panel 1i, description thereof will be omitted. Therefore, the following description will focus on the processing of the subtraction unit 41a, the decoding unit 58, the non-touch operation information storage unit 61, and the correction unit 62. Further, hereinafter, an orthogonal sequence or an M sequence will be described as an example of a code sequence for parallel driving.

Specifically, the code sequence (component system 1 or -1) of driving the first to Nth drive lines in parallel is: d ₁ = (d ₁₁ , d ₁₂ , ..., d _1N )

d ₂ = (d ₂₁ , d ₂₂ ,...,d _2N )

.

.

.

d _M = (d _M1 , d _M2 , ..., d _MN ), and the following sequence is converted into an M sequence of an orthogonal sequence or a code length N (= 2 ⁿ -1). Such a sequence has the property that the following formula holds.

[Number 1]

Here, when d ₁ ~d _M are orthogonal sequences, δ _ij =1 if i=j, δ _ij =0 if i≠j

When d ₁ ~d _M is the M sequence, if i=j then δ _ij =1, if i≠j then δ _ij =-1/N

The differential output sequence of the sensing line 33 corresponding to the sequence is "S _{j, P} (j = 1, ..., [L/2], P = 1, 2) (the number of the L-shaped sensing lines 33, [n] ] = the integer part of n) is defined as S _j,1 : the output sequence corresponding to d ₁ ~d _M when the switch SW is on the lower side

S _j,2 : output sequence corresponding to d ₁ ~d _M when the switch SW is on the upper side

In addition, the difference distribution of the capacitance values in the direction of the sensing line 33 "( sC) _kj,P (k=1,...,M,j=1,...,[L/2],P=1,2)” is defined as ( sC) _kj,1 =C _k,2j -C _k,2j-1

( sC) _kj,2 =C _k,2j+1 -C _k,2j

In this case, the differential output of the sense line direction of the capacitance generated by the parallel drive is as shown in the following equation.

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 values in the direction of the sensing line 33). specific In other words, the inner product of the difference between the code sequence of the parallel drive sense line 33 and the capacitance value of the sense line 33 direction is calculated. Therefore, the inner product value decoded by the decoding unit 58 is as shown in the following equation.

Here,

When d ₁ ~d _M is an orthogonal sequence, if i=j then δ _ij =1, if i≠j then δ _ij =0

When d ₁ ~d _M is an orthogonal sequence, if i=j then δ _ij =1, if i≠j then δ _ij =-1/N

In this way, the decoding unit 58 serves as the inner product value d _i after decoding. S _j, the main component of _P , calculates the difference distribution of the capacitance values in the direction of the N-folded sensing line 33 ( sC) _kj,P . Therefore, by the inner product value d _i . s _j,P as the differential distribution of the capacitance values in the direction of the sensing line 33 ( sC) _ij, the estimated value of _P , the signal intensity of the capacitor value can be read by N times (code length).

On the other hand, as described above, by defining the differential output sequence S _j,P (P = 1, 2) of the sensing line 33, the common mode noise overlapping on the adjacent sensing line 33 can be eliminated. Thereby, the differential capacitance with a higher SNR can be read.

As described above, the touch panel 3c drives the touch panel 3c in parallel, and the decoding unit 58 decodes the difference value of the capacitance calculated by the subtraction unit 41a. Therefore, since the electrostatic capacitance signal is obtained by the code length multiplication (N times), the signal strength of the electrostatic capacitance can be increased without depending on the number of the driving lines 35. Further, if it is the same signal intensity as the previous driving method shown in FIG. 9, the driving time of the driving line 35 can be shortened to 1/N in the driving mode shown in FIG. That is, the number of driving of the drive line 35 can be reduced. Thereby, the power consumption of the touch panel system 1j can be reduced.

Moreover, in the touch panel system 1j, the correction unit 62 preferably has a difference between the sensing lines 33 adjacent to each other calculated from the touch operation (that is, the difference value distribution of the touch panel 3c as a whole), and subtracts the non-touch operation. The difference between the sensing lines 33 adjacent to each other is calculated (= the difference value distribution of the entire touch operation). That is, it is preferable to perform the differential signal processing as described above before and after the touch operation, and to reduce the difference value signal before and after the touch operation. For example, the differential distribution of the initial state of the touchless operation (when not touched) sC) _kj, the estimated value of _P is stored in the non-touch operation information memory unit 61. Then, the correction unit 62 is differentially distributed from the touch operation ( sC) the estimated value of _kj minus the difference distribution when the non-touch operation of the information storage unit 61 is stored in the non-touch operation ( sC) _kj , the estimated value of P. Therefore, the correction unit 62 subtracts the difference distribution of the electrostatic capacitance during the non-touch operation of the information storage unit 61 during the non-touch operation from the difference distribution of the electrostatic capacitance during the touch operation (the difference in the touch operation) Value signal - the differential value signal for non-touch operation). Thereby, the inherent deviation of the touch panel 3c can be eliminated.

Thereby, in the touch panel system 1j, the difference component caused by the difference in capacitance inherent in the touch panel 3c is eliminated, and only the difference component caused by the touch operation is detected. In the case of the M sequence, there is an error component that cannot be carried in the orthogonal sequence (if not i≠j, δ _ij =-1/N). However, since the error component is caused only by the touch operation, if N is amplified by N=63 or 127, the degradation of SNR is small.

[Embodiment 12]

Fig. 23 is a schematic view showing the basic configuration of the touch panel system 1k of the embodiment. In the touch panel system 1k, the configuration of the subtraction unit 41a is different.

The output signal of the self-sensing line 33 of the touch panel 3c is analogous to the signal. Therefore, the subtraction unit 41a includes an AD conversion unit 48a (first AD conversion unit) and a digital subtractor (not shown).

Thereby, 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 subtractor performs the same subtraction processing as the touch panel systems 1i, 1j of FIG. 20 using the converted digital signal.

In this manner, the touch panel system 1k can perform the subtraction process by converting the analog signal output from the touch panel 3c into a digital signal, thereby removing noise.

[Embodiment 13]

Fig. 24 is a schematic view showing the basic configuration of the touch panel system 1m of the embodiment. In the touch panel system 1m, the configuration of the subtraction unit 41a is different.

The output signal of the self-sensing line 33 of the touch panel 3c is analogous to the signal. Therefore, the subtraction unit 41a includes the differential amplifier 49 and the AD conversion unit 48a (second AD conversion unit).

Thereby, the differential amplifier 49 directly performs the same subtraction processing as the touch panel system 1i of FIG. 20 by using the analog signal from the output signal (analog signal) of the touch panel 3c. The AD conversion unit 48a converts the analog signal after the subtraction process into a digital signal.

In this way, the touch panel system 1m can be directly converted into a digital signal by subtracting the analog signal from the analog signal outputted by the touch panel 3c, and then removing the noise.

[Embodiment 14]

Fig. 25 is a schematic view showing the basic configuration of the touch panel system 1n of the embodiment. In the touch panel system 1n, the configuration of the subtraction unit 41a is different. The touch panel system 1n includes a fully differential amplifier 50 in place of the differential amplifier 49 of the touch panel system 1m of FIG.

The output signal of the self-sensing line 33 of the touch panel 3c is analogous to the signal. Therefore, the subtraction unit 41a includes the fully differential amplifier 50 and the AD conversion unit 48a.

Thereby, the full differential amplifier 50 performs the same subtraction processing as the touch panel system 1i of FIG. 20 directly with the analog signal from the output signal (analog signal) of the touch panel 3c. The AD conversion unit 48a converts the analog signal after the subtraction process into a digital signal.

In this way, the touch panel system 1n can directly reduce the analog signal by the analog signal output from the touch panel 3c, and then convert the digital signal into a digital signal to remove the noise.

[Embodiment 15]

Fig. 26 is a schematic view showing the basic configuration of the touch panel system 1o of the embodiment. In the touch panel system 1o, the configuration of the subtraction unit 41a is different. The touch panel system 1o includes a fully differential amplifier 50 instead of the differential amplifier 49 of the touch panel system 1m of FIG.

The output signal of the self-sensing line 33 of the touch panel 3c is analogous to the signal. Therefore, the subtraction unit 41a includes the fully differential amplifier 50 and the AD conversion unit 48a.

Thereby, the fully differential amplifier 50 directly performs the same subtraction processing as the touch panel system 1i of FIG. 20 with the analog signal directly from the output signal (analog signal) of the touch panel 3c. The AD conversion unit 48a converts the analog signal after the subtraction process into a digital signal.

Further, in the touch panel system 1o, as the driving method of the touch panel 3c, the orthogonal sequence driving method shown in FIGS. 10, 12, and 22 is applied. In this case, as shown in FIG. 10, in the case of driving the voltages of the four driving lines in the second to fourth times, the number of times +V is applied is the same as the number of times -V is applied, and vice versa. In the first case, +V was applied 4 times. Therefore, the output value of the first output sequence Y1 is larger than the output values of the output sequences Y2 to Y4 of the second to fourth times. Therefore, if the output values of the output sequences Y2 to Y4 of the second to fourth times match the dynamic range, the output sequence Y1 of the first time becomes saturated.

Therefore, the subtraction unit 41a of the touch panel system 1o includes the fully differential amplifier 50.

Furthermore, the fully differential amplifier 50 employs an input common mode voltage range for rail-to-rail actor. That is, the fully differential amplifier 50 expands the input range of the common mode. Thereby, the fully differential amplifier 50 can operate in the voltage range of the power supply voltage (Vdd) to GND. In addition, the input signal differential of the fully differential amplifier 50 is amplified. Therefore, regardless of the combination of the orthogonal sequence driving method of the touch panel 3c, the output signal from the fully differential amplifier 50 does not cause an output saturation problem. In addition, an example of the fully differential amplifier 50 is as shown in FIG. 17 described above.

In this way, the touch panel system 1o can output the analog signal from the touch panel 3c. The number is directly subtracted by the analog signal, converted into a digital signal, and the noise is removed. Furthermore, since the fully differential amplifier 50, which can perform a rail-to-rail operation, does not cause an output saturation problem from the output signal of the fully differential amplifier 50.

[Embodiment 16]

Then, the method of identifying the touch operation of the touch panel system of the above embodiment will be described. Hereinafter, the touch panel system 1j of FIG. 22 will be described as an example, but the touch panel system of other embodiments is also the same. The touch panel system 1j includes a determination unit 59 (touch detection unit) that compares the signal difference between the adjacent sensing lines 33 calculated by the subtraction unit 41a and the decoding unit 58 with the positive and negative threshold values. Determine the presence or absence of touch operations. Further, the determination unit 59 receives a signal (a difference distribution of the electrostatic capacitance) corrected by the correction unit 62 or a signal (a differential distribution of the electrostatic capacitance) corrected by the uncorrected unit 62. When the signal of the correction processing by the uncorrection unit 62 is input to the determination unit 59, the difference distribution of the capacitances decoded by the decoding unit 58 is directly input to the determination unit 59. Hereinafter, a case where the signal that has not been subjected to the correction processing by the correction unit 62 is input to the determination unit 59 will be described. However, the same applies to the case where the signal subjected to the correction processing is input to the determining unit 59.

Fig. 27 is a flow chart showing the basic processing of the judging section 59 of the touch panel system 1j of Fig. 22. 28 is a schematic diagram showing a touch information identification method in the flowchart of FIG. 27.

As shown in FIG. 27, the determination unit 59 first acquires the difference value (difference distribution) of the adjacent or lined signals calculated by the subtraction unit 41a and the decoding unit 59. sC) _ij,P ” (F801). Next, the difference value is compared with the positive threshold THp and the negative threshold THm stored in the determination unit 59 to create an increase/decrease table (F802). This increase/decrease table is, for example, as shown in (a) of FIG. 28, and is a ternary increase/decrease table.

Then, the ternary increase and decrease table is converted into a binary image (binarization) (F803). For example, in the increase/decrease table of Fig. 28(a), when scanning is performed in the order of the sensing line S1 to the sensing line S7 (to the right in the figure), "+" appears in the increase and decrease table until the next "-" Everything that appears until it is converted to "1", and from the occurrence of "-", all contents in the opposite direction to the scanning direction (to the left in the figure) are converted to "1". Thereby, the binarized data as shown in FIG. 28(b) is obtained.

Next, in order to extract the touch information from the binarized data, the link component (F804) is extracted. For example, in FIG. 28(b), when the same sensing line position is overlapped by "1" on the adjacent driving line, it is regarded as the same connecting component, and is used as a touch position candidate. That is, in FIG. 28(c), the "1" surrounded by the frame is regarded as the same connection component, and is captured as a touch position candidate.

Finally, based on the captured touch position candidates, the touch information (touch size, touch position, etc.) is recognized (F805).

In this manner, the determination unit 59 determines the presence or absence of the touch operation based on the signal difference of the sensing lines 33 adjacent to each other from which the noise signals have been removed. Therefore, the presence or absence of the touch operation can be correctly determined.

Further, in the above example, the determination unit 59 compares the signal difference between the sensing lines 33 adjacent to each other calculated by the subtracting unit 41a, and the positive and negative thresholds (THp, THm), and compares the sensing lines. The differential distribution of the signal of 33 is valued as an increase/decrease table, and the increase/decrease table is converted into a binary image. That is, the signal differential input of the sensing lines adjacent to each other that have eliminated the noise signals is determined. Part 59. The determining unit 59 uses the signal difference between the sensing lines 33 adjacent to each other and the positive and negative thresholds (THp, THm) stored in the determining unit 59 to compare the differential distribution of the signals of the sensing lines 33 into three. Increase or decrease the table. Furthermore, the determination unit 59 converts the increase/decrease table into a binary image by binarizing the increase/decrease table. Thereby, the touch position candidate is extracted from the converted binary image. Therefore, based on the binary image, by recognizing the touch information (touch size, position, etc.), the touch information can be more accurately recognized in addition to determining the presence or absence of the touch operation.

[Embodiment 17]

FIG. 29 is a functional block diagram showing the configuration of the mobile phone 10 on which the touch panel system 1 is mounted. The mobile 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 a touch panel system 1. The constituent elements are connected to each other by a data bus.

The CPU 51 controls the operation of the mobile phone 10. The CPU 51 executes, for example, a program stored in the ROM 52. The operation key 57 receives an instruction input by the user of the mobile phone 10. The RAM 53 volatilely stores the data generated by the CPU 51 executing the program or the data input via the operation key 57. ROM 52 stores data non-volatilely.

Further, the ROM 52 is a ROM that can be written and erased, such as an EPROM (Erasable Programmable Read-Only Memory) or a flash memory. Further, although not shown in FIG. 20, the mobile phone 10 may be configured to include an interface (IF) for connecting other electronic devices by wire.

The camera 54 captures a subject according to the user's operation of the operation key 57. In addition, 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 the sound input by the user. The mobile phone 10 digitizes the input sound (analog data). And, the mobile phone 10 transmits the digitized sound to the communication object (for example, other mobile phones). The speaker 56 outputs sound based on, for example, music material stored in the RAM 53 or the like.

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 action of the touch panel system 1. The CPU 51 executes, for example, a program stored in the ROM 52. The RAM 53 volatilely stores data generated by the CPU 51 executing programs. ROM 52 stores data non-volatilely.

The display device 2 displays images stored in the ROM 52 and the RAM 53. The display device 2 is overlapped with the touch panel 3 or built into the touch panel 3 .

Further, the first feature can also be expressed as follows.

[1] A touch panel system, comprising: a touch panel comprising a plurality of sensors; and a touch panel controller that inputs a signal from the sensor and reads data; the touch panel The main sensor includes: a main sensor that inputs a signal by a touch operation; and a sub sensor that is disposed on the same touch panel as the main sensor; the touch panel controller includes: a subtraction mechanism, It receives the signal from the main sensor and the signal from the sub-sensor, and subtracts the signal from the sub-sensor from the signal from the main sensor.

[2] The touch panel system according to [1] above, wherein the sub sensor is not made The user touches by touch operation and detects noise generated by the sensor.

[3] The touch panel system according to [1] or [2] above, wherein the main inductor is disposed adjacent to the sub-sensor.

[4] A touch panel system, comprising: a display device; a touch panel disposed on an upper portion of a display image of the display device, and configured to configure a plurality of sensor groups in a matrix; and a panel controller that inputs a signal from the sensor and reads data; the touch panel includes: a main sensor group that inputs a signal by a touch operation by a user; and a sub sensor group, which is set On the same touch panel as the main sensor group; the touch panel controller includes: a subtraction mechanism that receives signals from the main sensor group and signals from the sub-sensor group, and from the above The signal from the sub-sensor group is subtracted from the main sensor group signal.

[5] The touch panel system according to [4] above, wherein the sub-sensor group is not contacted by a user by a touch operation, and noise generated by the sensor group is detected.

[6] The touch panel system according to [4] or [5] above, wherein the main sensor group is disposed adjacent to the sub sensor group.

[7] The touch panel system according to any one of [1] to [6] above, wherein the display device is a liquid crystal display, a plasma display, an organic EL display, and an FED display.

[8] An electronic device comprising the touch panel system according to any one of [1] to [7] above.

According to the above configuration, the touch panel includes: a main sensing portion, which is used The detecting touch operation is performed; and the auxiliary sensing unit is configured to detect the noise; and the subtraction unit obtains the signal difference between the main sensing unit and the auxiliary sensing unit. Thereby, the noise signal is removed from the output signal of the autonomous sensing unit, and the original signal of the touch operation generated by the touch operation is captured. Therefore, various types of noise reflected by the touch panel can be surely removed (eliminated). Therefore, the noise component to be removed is not limited to the AC signal component included in the signal of the noise, but is related to all the noise components reflected by the touch panel. That is, a touch panel system and an electronic machine that substantially eliminate all noise components can be provided.

<<2nd feature>>

(1) The composition of the touch panel system 1r

Fig. 30 is a schematic view showing the basic configuration of another touch panel system 1r of the present invention. The basic configuration of the touch panel system 1r is substantially the same as that of the touch panel systems 1 and 1a to 1o of the first feature. Hereinafter, the touch panel system 1r of the second feature will be described centering on the difference from the touch panel system 1 and 1a to 1o of the first feature. For the sake of convenience of explanation, members having the same functions as those of the touch panel systems 1 and 1a to 1o of the first feature will be denoted by the same reference numerals and will not be described.

As shown in FIG. 30, the touch panel system 1r includes: a display device 2, a touch panel 3, a touch panel controller 4, a driving line driving circuit 5, and touch information generated by the touch panel controller 4 (touch The area setting unit 8 that sets the effective area on the touch panel 3 and generates the effective area information by controlling the size, the touch position, and the like.

The drive line drive circuit 5 acquires the effective area information and grasps the effective area set by the area setting unit 8. Next, the drive line drive circuit 5 is based on The effective area set by the area setting unit 8 drives each of the drive lines 35. A specific example of a method of driving the drive line 35 by the drive line drive circuit 5 will be described later.

The touch panel controller 4 includes an amplifying portion 71 (for example, a differential amplifying portion 49 or a full differential amplifying portion 50 described in the first feature) for amplifying the signal of the sensing line 33; the signal obtaining portion 72. The signal amplified by the amplification unit 71 is obtained and outputted in a time-sharing manner. The AD conversion unit 73 (for example, the AD conversion units 48 and 48a described in the first feature) may output the signal acquisition unit 72. The analog signal is converted into a digital signal; the decoding unit 58 determines the difference distribution of the electrostatic capacitance based on the digital signal converted by the AD conversion unit 73; and the difference detection of the electrostatic capacitance obtained by the coordinate detecting unit 42 based on the decoding unit 58. , generate touch information.

The amplification unit 71 and the signal acquisition unit 72 respectively acquire the effective area information and grasp the effective area set by the area setting unit 8. Next, the amplifying unit 71 performs signal amplification of the sensing line 33 based on the effective area set by the area setting unit 8. Further, the signal acquisition unit 72 selects the signal of the sensing line 33 amplified by the amplification unit 71 based on the effective area set by the area setting unit 8, and outputs it in time division. Further, a specific example of a method or an acquisition method for amplifying a signal 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 of a specific number of bits. Further, although the number of bits of the digital signal generated by the AD conversion unit 73 is not limited to the number of bits, the accuracy of the processing of the rear decoding unit 58 and the coordinate detecting unit 42 (the detection accuracy of the touch position) is considered. For example, it is below 12 bits and 16 bits or less.

The area setting unit 8 includes an effective area calculation unit 81 that sets an effective area on the touch panel 3 based on the touch information, and generates position information of the effective area, and a storage unit 82 that stores the operation of the effective area calculation unit 81. Required parameters, etc.

The effective area calculation unit 81 includes, for example, a CPU (for example, corresponding to the CPU 43), acquires touch information, and grasps the 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 temporary storage unit 821 for storing parameters necessary for the calculation of the effective area calculation unit 81 and the like. The specific example of the calculation content (the setting method of the effective area) of the effective area calculation unit 81 will be described later.

(2) The first operation example of the touch panel system

Next, a first operation example of the touch panel system 1r shown in FIG. 30 will be described with reference to the drawings. First, an example of an effective area set by the area setting unit 8 on the touch panel 3 will be described with reference to the drawings. Figure 31 is a block diagram showing 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. Further, the drive line 35r and the induction line 33r (thick solid line in the drawing) pass through the effective area, respectively. In other words, at least a part of each of the electrostatic capacitances generated by the driving line 35r and the sensing line 33r is included in the effective area A.

For example, in the case where the effective area A as shown in FIG. 31 is set, the drive line drive circuit 5 applies a drive signal to each of the drive lines 35r passing through the effective area A. On the other hand, the drive line drive circuit 5 does not pass the active area A. A drive signal is applied to each drive line.

A specific example of a method of driving the drive line 35 by the drive line drive circuit 5 will be described with reference to the drawings. Fig. 32 is a view showing an example of a specific driving method of the driving line driving circuit for the driving line in the first operation example. 32(a) shows a case where the entire surface of the touch panel 3 is set as an effective area, and FIG. 32(b) shows a case where one portion of the touch panel 3 is set as an effective area (setting FIG. 31 is shown). The case of the effective area A).

As shown in FIG. 32(a), the entire surface of the touch panel 3 is set as an effective area, and the drive line drive circuit 5 applies a drive signal to all of the drive lines 35. For example, the drive line drive circuit 5 applies a set inherent drive signal to each of the drive lines DL. The drive signal system includes a combination of a high level ("1") and a low level ("0"), and the signal level changes with respect to the time direction. In addition, the driving signal may also be a code sequence described by the first feature. In addition, the lower level of the drive signal can also be "-1".

On the other hand, as shown in FIG. 32(b), in a case where the effective area A is set in one portion of the touch panel 3, the drive line drive circuit 5 applies a drive signal to the drive line 35r passing through the effective area A. At this time, the drive line drive circuit 5 applies the above-described inherent drive signal to the drive line 35r. Further, the drive line drive circuit 5 grounds the drive lines that have not passed through the active area A, and suppresses the change of the signal level of the drive lines with time.

Therefore, in the example shown in Fig. 32 (b), the driving signal applied to the driving line 35r passing through the effective area A is the same as the driving signal applied to the driving line 35r in the case shown in Fig. 32 (a). . Furthermore, in the example shown in FIG. 32(b), the signal level of the driving line that does not pass the effective area A is for the time side. The constant value is "0". In addition, if the signal level of the driving line that does not pass the effective area A does not change with respect to the time direction, the value is not limited to "0", and may be "1" or a combination of "1" and "0". (For example, one of the two adjacent drive lines is "0" and the other is "1").

Thus, if the drive line drive circuit 5 selectively drives the drive line 35r passing through the effective area A, useless driving of the drive line 35 can be prevented. Therefore, the power consumption of the driving drive line 35 can be reduced, noise generation can be suppressed, and the detection sensitivity of the touch operation can be improved. In addition, the detection accuracy of the touch position in the touch panel controller 4 can be improved by driving the driving line 35r in a limited manner.

Moreover, since the driving line driving circuit 5 controls the driving line 35 in the manner shown in FIG. 32, the driving line controller 4 (in particular, the decoding unit 58) can easily recognize the signal variation of the sensing line 33 generated by the touch operation. .

Further, for example, when the effective area A shown in FIG. 31 is set, the amplifying unit 71 selectively amplifies the signal passing through the sensing line 33r of the effective area A. A specific operation example of the amplifying unit 71 will be described with reference to the drawings. Fig. 33 is a block diagram showing an example of a specific operation of the amplifying unit in the first operation example.

As shown in FIG. 33, the amplifying portion 71 includes an amplifier 711 corresponding to the sensing line 33, and an opening and closing switch 712 that controls whether or not the signal of the sensing line 33 is supplied to the amplifier 711. However, each of the open/close switches 712 is controlled based on the effective area information.

Specifically, the open/close switch 712 that supplies the signal through the sensing line 33r of the effective area A is turned on. Thereby, the signal passing through the sensing line 33r of the effective area A is amplified by the amplifier 711, and is output from the amplifying portion 71. On the other hand, an opening and closing switch 712 that supplies a signal that does not pass through the sensing line of the effective area A In the non-conducting state. Thereby, the sense line signal that has not passed through the effective area A is not amplified by the amplifier 711 and is not output from the amplification unit 71.

Thus, by the amplification unit 71 selectively amplifying the signal passing through the sensing line 33r of the effective area A, the power consumption of the signal amplification can be reduced. Further, the structure for selectively amplifying the sensing line 33r signal is not limited to the illustrated amplifier 711 and the opening and closing switch 712, and may have other configurations as long as the same effect can be obtained. For example, an active/inactive switch of the switchable amplifier 711 can also be included to replace (or add) the open/close switch 712.

Further, the signal acquisition unit 72 selectively acquires the signal passing through the sensing line 33r of the effective area A, and outputs it in time division. A specific operation example of the signal acquisition unit 72 will be described with reference to the drawings. Fig. 34 is a block diagram showing an example of a specific operation of the selection acquisition unit in the first operation example.

As shown in FIG. 34, the signal acquisition unit 72 includes a branch switch 721 which selects one of the terminals corresponding to each of the sensing lines 33 and is connected to the subsequent stage. However, the branch switch 721 is controlled based on the effective area information.

Specifically, the branch switch 721 is connected to a terminal corresponding to the sensing line 33r passing through the effective area A. Thereby, the signal amplified by the amplifying portion 71 through the sensing line 33r of the effective area A is output to the subsequent stage. On the other hand, the branch switch 721 is not connected to the terminal corresponding to the sensing line that does not pass through the active area A. Thereby, the signal of the sensing line that has not passed through the effective area A is not output to the subsequent stage.

In this manner, the signal acquisition unit 72 selectively acquires the signal passing through the sensing line 33r of the effective area A and outputs it in time division, thereby preventing the useless signal from being output to the subsequent stage of the signal acquisition unit 72. Therefore, 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 detecting unit 42) can be reduced. power consumption. Further, the structure for selectively acquiring signals and outputting time-division is not limited to the illustrated branch switch 721, and may have other configurations as long as the same effect can be obtained.

Then, the AD conversion unit 73 converts the analog signal outputted by the signal acquisition unit 72 into a digital signal, and the decoding unit 58 determines the differential distribution of the electrostatic capacitance of the touch panel 3 (the active area A) based on the digital signal, and coordinates the coordinates. The detecting unit 42 detects the touch position of the touch panel 3 (the active area A) by referring to the difference distribution, thereby generating touch information.

Thus, the touch panel controller 4 selectively processes the signal passing through the sensing line 33r of the active area A. Therefore, useless signal processing can be prevented. Thereby, the power consumption of the signal processing can be reduced. In addition, by limiting the signal passing through the sensing line 33r of the effective area A, the detection accuracy of the touch position can be improved.

As described above, the touch panel controller 4 performs an operation based on the effective area A set by the area setting unit 8. On the other hand, 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.

Hereinafter, an example of a series of operations specific to the area setting unit 8 will be described with reference to the drawings. Fig. 35 is a flow chart showing an example of a specific operation of the area setting unit in the first operation example. FIG. 36 is a view showing an example of a method of setting an effective area in the first operation example.

For convenience of explanation, as shown in FIG. 36, the position of the induction line 33 in the entire column direction (the vertical direction in the drawing, and the X direction) is taken as X, and the position of the drive line 35 in the entire column direction (the horizontal direction in the drawing and the Y direction) is referred to as Y. And with coordinates (X, Y) The position inside the touch panel 3 is indicated. Further, the coordinates of the upper left corner of the touch panel 3 are set to (0, 0), and the coordinates of the lower right corner are set to (n, m). Among them, at least one of n and m is a natural number of 2 or more, and the touch panel 3 is provided with n sensing lines 33 and m driving lines 35. Further, the coordinates of the upper left corner of the effective area A are set to (Xs, Ys), and the coordinates of the lower right corner of the effective area A are set to (Xe, Ye).

In addition, FIG. 36 illustrates a case where the effective area A is centered on the touch position (Xp, Yp), and the length in the X direction is WD_S and the length in the Y direction is WD_D. The details of the setting method of the effective area A will be described later.

As shown in FIG. 35, when the operation of the touch panel system 1r is started, the effective area calculation unit 81 sets an effective area which is the entire surface of the touch panel 3, and calculates (Xs, Ys) = (0, 0) and ( Xe, Ye) = (n, m) effective area information (step #1). Next, the effective area calculation unit 81 outputs the calculated effective area information (step #2).

Next, the effective area calculation unit 81 acquires the touch information generated by the touch panel controller 4 (step #3). At this time, the effective area calculation unit 81 confirms the "dot drive mode" (first mode) in which the new effective area is set based on the touch position, by confirming the parameter stored in the register 821 of the storage unit 82, or The "full-surface detection mode" (second mode) in which the entire surface of the touch panel 3 is set as the new effective area is continued (step #4).

The "dot drive mode" and the "full face detection mode" can be switched, for example, by an instruction (operation) of the user. Therefore, the user can reduce the power consumption and improve the detection sensitivity of the touch operation, such as the "point drive mode" and the self-touch surface, for example, according to the setting environment or the use environment of the touch panel system. The entire surface of the panel 3 is provided with any one of the "full-surface detection modes" for detecting the touch position, and the touch panel system 1r is operated. In addition, the configuration of the touch panel system 1r can also automatically select these modes to operate according to factors other than the user's instruction.

In the case of the "full-surface detection mode" (steps #4 and NO), the effective area calculation unit 81 is set to be a new effective area of the entire surface of the touch panel 3, and calculates (Xs, Ys) = (0, 0) and ( Xe, Ye) = (n, m) effective area information (step #5). Next, the effective area calculation unit 81 outputs the calculated effective area information (step #6).

Then, when the new touch information is output (step #7, YES), the process returns to step #3, and the touch information is obtained. On the other hand, the case where the new touch information is not output (step #7, NO) ends the operation.

In the case of the "dot drive mode" (step #4, YES), when the touch position on the touch panel 3 is not calculated (steps #8, NO), the effective area calculation unit 81 performs the above-mentioned "full-surface detection". The same action as in the mode (steps #5~#7). Therefore, since the effective area is set on the entire surface of the touch panel 3, the touch panel controller 4 can detect the touch operation regardless of which position on the touch panel 3 is touched, and detect the touch operation. Touch location.

On the other hand, in the case of the "dot drive mode" (step #4, YES), when the touch position on the touch panel 3 is calculated (step #8, YES), the effective area calculation unit 81 should be set to include As shown in FIG. 36, the new effective area of the touch position is calculated as Xs=Xp-WD_S/2, Ys=Yp-WD_D/2, Xe=Xp+WD_S/2, and Ye=Yp+WD_D/2. region Information (step #9). Next, the effective area calculation unit 81 outputs the calculated effective area information (step #6). Thereby, the effective area calculation unit 81 can set a new effective area A including a higher possibility of detecting the position of the touch position.

Then, when the new touch information is output (step #7, YES), the process returns to step #3, and the touch information is obtained. On the other hand, the case where the new touch information is not output (step #7, NO) ends the operation.

As described above, in the touch panel system 1r of the present embodiment, the effective area of the area where the touch position detection should be performed is limitedly set in the touch panel 3 based on the detected touch position. Therefore, by avoiding useless detection, power consumption can be reduced, and the detection sensitivity of the touch operation can be improved.

The operation of the touch panel controller 4 and the operation of the area setting unit 8 (the operations of steps #3 to #9 in FIG. 35) are repeated at a specific frame update rate (for example, 120 Hz). get on.

Further, although the effective area calculation unit 81 sequentially confirms the "dot drive mode" or the "full-surface detection mode" (step #4) during the operation, the confirmation may be performed one by one. For example, the effective area calculation unit 81 performs the confirmation after step #2, and thereafter, regardless of the instruction input by the user or the like, the operation can be performed in accordance with the mode of each.

Further, the size of the effective area (for example, WD_D and WD_S) set by the area setting unit 8 may be a fixed value or a variable value. If the effective area size is a variable value, if the area setting unit 8 sets the size of the new effective area according to the moving speed of the touch position, the possibility that the next touch position is included in the new effective area is high. Therefore, it is better.

An example of a specific setting method of the effective area in this case will be described with reference to FIG. Fig. 37 is a view showing another example of the method of setting the effective area in the first operation example. FIG. 8 illustrates a case where the touch position of the current screen is (Xpa, Ypa) and the touch position of the next screen is (Xpb, Ypb). Further, the moving speed in the X direction of the touch position in the current frame is taken as Vx, the moving speed in the Y direction is Vy, and the screen update rate is taken as f.

The area setting unit 8 sets the new effective area by including the touch position (Xpb, Ypb) in the next screen based on the touch position (Xpa, Ypa) and the moving speed (Vx, Vy) in the current screen. In other words, the area setting unit 8 sets the new effective area so that WD_S ≧ 2 × Vx / f and WD_D ≧ 2 × Vy / f. For example, when Vy = 1000 mm/s and f = 120 Hz, it becomes WD_D ≧ 16.7 mm.

Moreover, the area setting unit 8 may store the sequentially acquired touch positions in the storage unit 82, determine the amount of change in the touch position, and determine the moving speed of the touch position in the current screen based on the amount of change.

Further, the area setting unit 8 does not have to set an effective area centered on the touch position. For example, when the touch position is detected near the edge of the touch panel 3, the area setting unit 8 can also set the effective area where the touch position is biased toward the side end. Further, the area setting unit 8 can also set an effective area based on the moving direction of the touch position. For example, the area setting unit 8 may also set an effective area in which the touch position is biased in a direction opposite to the moving direction of the touch position.

(3) The second operation example of the touch panel system

The touch panel system 1r shown in FIG. 30 detects the touch position by the touch panel controller 4 based on the differential distribution of the electrostatic capacitance of the touch panel 3, that is, The touch panel 3 has a plurality of touch positions, and each touch position can be detected separately (corresponding to multi-touch). Therefore, an operation example (second operation example) of the touch panel system 1r corresponding to multi-touch will be described below.

In the second operation example, the touch panel controller 4 can detect a plurality of touch positions, and the area setting unit 8 can set the effective area based on the plurality of touch positions, but the basic operation system and the first operation example Common. Therefore, in the following description of the second operation example, the part common to the first operation example is appropriately described with reference to the first operation example, and a detailed description thereof will be omitted.

First, an example of an effective area set in the touch panel 3 by the area setting unit 8 will be described with reference to the drawings. 38 is a block diagram showing an example of an effective area set in the touch panel 3 in the second operation example. In addition, FIG. 38 illustrates effective areas A1 and A2 set in the case where two touch positions are separated on the touch panel 3.

The effective areas A1 and A2 illustrated in FIG. 38 are respectively set in the area of one portion of the touch panel 3. Further, the driving line 35r1 and the sensing line 33r1 (thick solid line in the drawing) pass through the effective area A1, respectively, and the driving line 35r2 and the sensing line 33r2 (thick solid line in the drawing) pass through the effective area A2, respectively. In other words, at least a part of each detection region X formed by the driving line 35r1 and the sensing line 33r1 is included in the effective area A1, and at least a part of each detection area X generated by the driving line 35r2 and the sensing line 33r2 is included in the effective area A2.

For example, in the touch panel 3, in the case where the effective areas A1 and A2 are set as shown in FIG. 38, the driving line driving circuit 5 respectively drives the driving line 35r1 passing through the effective area A1 and the driving line 35r2 passing through the effective area A2. Apply a drive signal. On the other hand, the drive line drive circuit 5 does not have a separate pass A drive signal is applied to the drive lines of any of the effect areas A1 and A2.

In the second operation example, a specific example of the method of driving the drive line 35 by the drive line drive circuit 5 will be described with reference to the drawings. Fig. 39 is a view showing an example of a specific driving method of the driving line by the driving line driving circuit in the second operation example.

As shown in FIG. 39, the drive line drive circuit 5 applies the above-described unique drive signal to the drive line 35r1 passing through the effective area A1 and the drive line 35r2 passing through the effective area A2 (see FIG. 32). Further, the drive line drive circuit 5 is configured to ground the drive lines that have not passed through any of the effective areas A1 and A2, and to suppress the change of the signal level of the drive lines with time.

Thus, in the multi-touch, the drive line drive circuit 5 can also prevent the drive line 35 from being uselessly driven by selectively driving the drive lines 35r1, 35r2 through the active areas A1, A2. Therefore, the power consumption of the driving consumption of the driving line 35 can be reduced, noise generation can be suppressed, and the detection sensitivity of the touch operation can be improved. Moreover, by selectively driving the driving lines 35r1, 35r2, the detection accuracy of the touch position in the touch panel controller 4 can be improved.

Further, for example, when the effective areas A1 and A2 shown in FIG. 38 are set in the touch panel 3, the amplifying unit 71 selectively amplifies the respective signals passing through the sensing line 33r1 of the effective area A1 and the sensing line 33r2 passing through the effective area A2. . Specific operational examples of the amplifying unit 71 will be described with reference to the drawings. Fig. 40 is a block diagram showing an example of a specific operation of the amplifying unit in the second operation example. The amplifying portion 71 shown in FIG. 40 is the same as the amplifying portion 71 (see FIG. 33) described in the first operation example.

As shown in FIG. 40, the sensing line 33r1 passing through the effective area A1 is respectively supplied. And the opening and closing switch 712 of each signal passing through the sensing line 33r2 of the effective area A2 is turned on. Thereby, the signals passing through the sensing line 33r1 of the effective area A1 and the sensing line 33r2 passing through the effective area A2 are amplified by the amplifier 711 and output from the amplifying portion 71. On the other hand, the opening and closing switch 712 that supplies the sensing line signal that has not passed through any of the effective areas A1 and A2 is in a non-conduction state. Thereby, the sense line signal that has not passed through any of the effective areas A1 and A2 is not amplified by the amplifier 711 and is not output from the amplification unit 71.

Thereby, the amplifying unit 71 can reduce the power consumption of the signal amplification of the sensing line 33 by selectively amplifying the signals passing through the sensing lines 33r1 and 33r2 of the effective areas A1 and A2.

Further, the signal acquisition unit 72 selectively acquires the signal passing through the sensing line 33r1 of the effective area A1 and the signal passing through the sensing line 33r2 of the effective area A2, and outputs the time division. A specific operation example of the signal acquisition unit 72 will be described with reference to the drawings. 41 is a block diagram showing an example of a specific operation of the selection acquisition unit in the second operation example. The signal acquisition unit 72 shown in FIG. 41 is the same as the signal acquisition unit 72 (see FIG. 34) described in the first operation example.

As shown in FIG. 41, the branch switch 721 can be connected to terminals corresponding to the sensing line 33r1 passing through the active area A1 and the sensing line 33r2 passing through the effective area A2, respectively. Thereby, the signal amplified by the amplifying portion 71 through the sensing line 33r1 of the effective area A1 and the signal amplified by the amplifying portion 71 through the sensing line 33r2 of the effective area A2 are respectively output to the subsequent stage. On the other hand, the branch switch 721 is not connected to a terminal corresponding to the sensing line that does not pass through any of the effective areas A1, A2. Thereby, the signal of the sensing line that has not passed through any of the effective areas A1, A2 is not output to the latter stage.

In this manner, the signal acquisition unit 72 selectively acquires the signals passing through the sensing lines 33r1 and 33r2 of the effective areas A1 and A2 and outputs them in time division, thereby preventing the unnecessary signals from being output to the subsequent stage of the signal obtaining unit 72. Therefore, the power consumption consumed by the processing of the subsequent stages of the signal acquisition unit 72 (for example, the AD conversion unit 73, the decoding unit 58, and the coordinate detecting unit 42) can be reduced.

Then, the AD conversion unit 73 converts the analog signal outputted by the signal acquisition unit 72 into a digital signal, and the decoding unit 58 determines the difference distribution of the electrostatic capacitances of the touch panel 3 (the effective area A1 and the effective area A2) based on the digital signal. The coordinate detection unit 42 refers to the difference distribution to detect the touch position of the touch panel 3 (the active areas A1 and A2), thereby generating touch information. In addition, at this time, the decoding unit 58 and the coordinate detecting unit 42 can detect not only the touch position but also the driving line 35r2 and the sensing line 33r1 on the effective areas A1 and A2, even in the area where the driving line 35r1 and the sensing line 33r2 pass. The touch position is detected on the area through which it passes.

Thus, in multi-touch, the touch panel controller 4 can prevent useless signal processing by selectively processing the signals passing through the sensing lines 33r1, 33r2 of the active areas A1, A2. Thereby, the power consumption consumed by the signal processing can be reduced. In addition, by performing limited processing on the signals passing through the sensing lines 33r1 and 33r2 of the effective areas A1 and A2, the detection accuracy of the touch position can be improved.

Next, a specific series of operation examples in which the area setting unit 8 sets (updates) the effective area will be described with reference to the drawings. Fig. 42 is a flow chart showing an example of a specific operation of the area setting unit in the second operation example. In addition, FIG. 43 is a view showing an example of a method of setting an effective area in the second operation example. In the following, similarly to the description of the first operation example (see FIG. 36), the position of the entire alignment direction of the induction line 33 (the vertical direction in the FIG. 43 and the X direction) is taken as X, and the alignment direction of the drive line 35 is shown. The position of the left-right direction and the Y-direction of 43 is Y, and the position inside the touch panel 3 is represented by a coordinate (X, Y), and the coordinates of the upper left corner of the touch panel 3 are set to (0, 0), which will be right. The lower corner coordinates are set to (n, m). Further, the upper left corner coordinate of the effective area Ai is set to (Xsi, Ysi), and the lower right corner coordinate of the effective area Ai is set to (Xei, Yei).

i is a number for identifying the effective area and the effective area information, and may take a value of 1 or more and max or less (max is a natural number of 2 or more). That is, the max-based area setting unit 8 can set the upper limit of the number of effective areas, for example, it can be equal to the number of touch positions detectable by the touch panel controller 4. By setting the number of effective areas that can be set by the drive setting unit 8 to the upper limit value (max), the calculation amount of the area setting unit 8 can be suppressed from being excessive, and the total area of the effective area set by the area setting unit 8 is too large. Therefore, it is better.

FIG. 43 illustrates that the effective area A1 is centered on the touch position (Xp1, Yp1), the length in the X direction is set to WD_S1, the length in the Y direction is set to WD_D1, and the effective area A2 is centered on the touch position (Xp2, Yp2). The case where the length in the X direction is WD_S2 and the length in the Y direction is WD_D2. The details of the setting method of the effective areas A1 and A2 will be described later.

As shown in FIG. 42 , when the touch panel system 1 r starts, the effective area calculation unit 81 sets an effective area that is the entire surface of the touch panel 3 and calculates (Xs1, Ys1)=(0, 0). (Xe1, Ye1) = (n, m) effective area information. In this case, the effective area calculation unit 81 may calculate the effective area information of the remaining i=2 to max as a certain value, but in this example, it is i=1. The effective area information is the same, and is calculated as (Xsi, Ysi) = (0, 0) and (Xei, Yei) = (n, m) (step #11).

Next, the effective area calculation unit 81 outputs the effective area information of i=1 to max calculated in step #11 (step #12). In addition, each part of the touch panel controller 4 performs driving of the driving line 35 or signal processing of the sensing line 33 based on the effective area A1 corresponding to the effective area information of i=1, but is effective for i=2~max. Regional information is ignored.

Next, the effective area calculation unit 81 acquires the touch information generated by the touch panel controller 4 (step #13). At this time, the effective area calculation unit 81 confirms the "dot drive mode" (first mode) or the "full-surface detection mode" by confirming the parameter stored in the register 821 of the storage unit 82. 2 mode) (step #14).

In the case of the "full-surface detection mode" (step #14, NO), the effective area calculation unit 81 sets a new effective area which is the entire surface of the touch panel 3, and calculates (Xs1, Ys1) = (0, 0) And (Xe1, Ye1) = (n, m) effective area information. In this case, the effective area calculation unit 81 may calculate the effective area information of the remaining i=2 to max as a certain value. However, in this example, the effective area information of i=1 is the same as (Xsi, Ysi)=(0,0) and (Xei,Yei)=(n,m) are calculated (step #15).

Next, the effective area calculation unit 81 outputs the effective area information of i=1 to max calculated in step #15 (step #16). In addition, each part of the touch panel controller 4 performs driving of the driving line 35 or signal processing of the sensing line 33 based on the effective area A1 corresponding to the effective area information of i=1, but is effective for i=2~max. Regional information is ignored.

Then, when the new touch information is output (step #17, YES), the process returns to step #13, and the touch information is obtained. On the other hand, the case where the new touch information is not output (step #17, NO) ends the operation.

In the case of the "dot drive mode" (step #14, YES), if the touch position on the touch panel 3 is not detected (step #18, NO), the effective area calculation unit 81 performs the above-mentioned "complete" The same action as in the face detection mode (steps #15 to #17). Therefore, since the effective area is set on the entire surface of the touch panel 3, the touch panel controller 4 can detect the touch position regardless of which position on the touch panel 3 is subsequently touched.

On the other hand, in the case of the "dot drive mode" (step #14, YES), when the touch position on the touch panel 3 is detected (step #18, YES), the effective area calculation unit 81 should set the touch. The new effective area of the control position, for example, as shown in FIG. 43, is calculated as i = Xpi - WD_Si / 2, Ysi = Ypi - WD_Di / 2, Xei = Xpi + WD_Si / 2, and Yei = Ypi + WD_Di / 2 New effective area information of 1~num (in the example of Fig. 43, num=2). In other words, the number of effective areas set by the num-based effective area calculation unit 8 may be equal to, for example, the number of touch positions calculated by the touch panel controller 4. In this case, the effective area calculation unit 81 may calculate the effective area information of the remaining i=num+1~max as a certain value, but in this example, it is (Xsi, Ysi)=(0, 0) and (Xei, Yei) = (n, m) is calculated (step #19).

Next, the effective area calculation unit 81 outputs the effective area information of i=1 to max calculated in step #19 (step #16). In addition, each part of the touch panel controller 4 performs driving of the driving line 35 or signal processing of the sensing line 33 based on the effective areas A1 to Anum corresponding to the effective area information of i=1~num. However, the valid area information about i=num+1~max is ignored. Thereby, the effective area calculation unit 81 can set the new effective areas A1 to Anum which are highly likely to include the subsequent touch positions.

Then, when the new touch information is output (step #17, YES), the process returns to step #13 and the touch information is obtained. On the other hand, the case where the new touch information is not output (step #17, NO) ends the operation.

As described above, in the touch panel 1r of the present embodiment, when the touch panel controller 4 detects a plurality of touch positions (at the time of multi-touch), the area setting unit 8 can also set the effective area. In the touch panel system 1r of the present embodiment, the effective area for detecting the touch position based on the detected touch positions is limited to be set in the touch panel 3. Therefore, by avoiding useless detection, power consumption can be reduced, and the detection sensitivity of the touch operation can be improved.

Moreover, in the touch panel system 1r of this example, the effective areas corresponding to the detected touch positions are individually set. Therefore, a gap (a region of the non-effective area) can be provided between the effective areas set by the area setting unit 8. Therefore, the total area of the effective area set by the area setting unit 8 can be reduced.

The operation of the touch panel controller 4 and the operation of the area setting unit 8 (the operations of steps #13 to #19 in FIG. 42) are repeated at a specific screen update rate (for example, 120 Hz).

Further, the effective area calculation unit 81 sequentially confirms the "dot drive mode" or the "full-surface detection mode" (step #14) during the operation, but may not perform the confirmation one by one. For example, the effective area calculation unit 81 may perform the confirmation after step #12, and then input any instruction from the user or the like, and then perform the operation corresponding to each mode.

Further, when the effective area calculation unit 81 is in the "dot drive mode", whether or not the touch position is detected by the touch panel controller 4 can be set as a touch panel by a specific timing (for example, for each specific number of screens). 3 new effective area of the whole face. Specifically, for example, in FIG. 42, it is determined whether or not a specific timing is performed before step #18, and if it is a specific timing, step #15 is performed, otherwise, step #18 is performed.

In this manner, the area setting unit 8 performs touch operation on other parts of the touch panel 3 after the action (point drive) of sequentially setting the effective area corresponding to the touch position detected by the touch panel controller 4 in sequence. The operation is also determined by the touch panel controller 4 because the specific timing is set to be an effective area of the entire surface of the touch panel 3.

Further, the size of the effective area (for example, WD_Di and WD_Si) set by the area setting unit 8 may be the same, but may be different for each effective area (per i). Further, the size of the effective area (for example, WD_Di and WD_Si) set by the area setting unit 8 may be a fixed value or a variable value. When the size of the effective area is a variable value, as described in the first operation example (see FIG. 37), when the area setting unit 8 sets the size of the new effective area in accordance with the moving speed of the touch position, it is detected next. It is preferred that the position of the touch position is more likely to be included in the new effective area.

An example of a specific setting method of the effective area in this case will be described with reference to FIG. Fig. 44 is a view showing another example of the method of setting the effective area in the second operation example. 44 shows that the first touch position of the current screen is (Xp1a, Yp1a), the second touch position is (Xp2a, Yp2a), and the first touch position in the next screen is (Xp1b, Yp1b), and the second The touch position is (Xp2b, The case of Yp2b). Further, the moving speed in the X direction of the first touch position on the current screen is taken as Vx1, and the moving speed in the Y direction is Vy1, and the moving speed in the X direction of the second touch position in the current screen is taken as Vx2, and the moving in the Y direction. The speed is Vy2, and the picture update rate is taken as f.

The area setting unit 8 sets a new effective manner based on the first touch position (Xp1a, Yp1a) and the moving speed (Vx1, Vy1) in the current screen, including the first touch position (Xp1b, Yp1b) in the next screen. region. In other words, the area setting unit 8 sets the new effective area so that WD_S1≧2×Vx1/f and WD_D1≧2×Vy1/f. Similarly, the area setting unit 8 sets the second touch position (Xp2a, Yp2a) and the moving speed (Vx2, Vy2) in the current screen to include the second touch position (Xp2b, Yp2b) in the next screen. New effective area. In other words, the area setting unit 8 sets the new effective area so that WD_S2≧2×Vx2/f and WD_D2≧2×Vy2/f.

Further, in the area setting unit 8, the touch positions sequentially acquired may be stored in the storage unit 82, and the amount of change in each touch position may be obtained, and based on the amount of change, each touch in the current screen may be obtained. The speed at which the position moves.

Further, the area setting unit 8 does not necessarily set the effective area of each of the respective touch positions. For example, when detecting a certain touch position near the edge of the touch panel 3, the area setting unit 8 may also set the effective area of the touch position to the side end side. Further, the area setting unit 8 can also set the effective area based on the moving position of the touch position. For example, the area setting unit 8 may also set an effective area in which the touch position is biased in a direction opposite to a moving direction of a certain touch position.

Further, in the description of the second operation example up to now, although the touch surface is mainly illustrated The two touch positions on the board 3 are separated. However, as shown in FIG. 30, the touch panel system 1r can perform the same action even if there are more than three touch positions on the touch panel 3. This will be described with reference to the drawings. 45 is a block diagram showing another example of an effective area set in the touch panel in the second operation example. In addition, in FIG. 45, the case where the three touch positions on the touch panel 3 are separated is exemplified.

As shown in FIG. 45, even if there are three touch positions on the touch panel 3, the area setting unit 8 can set the effective areas A1 to A3 corresponding to the respective touch positions (see FIG. 42). At this time, 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. Moreover, the touch panel controller 4 at this time may selectively process each of the signals passing through the sensing line 33r1 of the effective area A1, the sensing line 33r2 passing through the effective area A2, and the sensing line 33r3 passing through the effective area A3. Further, the drive lines 35r1 to 35r3 and the sense lines 33r1 to 33r3 are indicated by thick solid lines in the drawing.

In this manner, even if the number of touch positions on the touch panel 3 fluctuates, the area setting unit 8 can change only the driving line to be driven or the sensing line to be processed by the fluctuation of the set effective area. Therefore, the touch panel system 1r shown in FIG. 30 can be used in a multi-touch with more than three touch positions on the touch panel 3, and can have two touch positions (refer to Figures 38 to 44) correspond to each other.

However, in the description of the second operation example, the case where the touch positions on the touch panel 3 are separated is exemplified, but the touch position on the touch panel 3 may be close. In this case, regarding FIG. 30 The operation example of the touch panel system 1r will be described with reference to the drawings. Fig. 46 is a block diagram showing another example of the effective area set in the touch panel in the second operation example. In addition, in FIG. 46, the case where the two touch positions on the touch panel 3 are close to each other is illustrated.

As shown in FIG. 46, when the touch position on the touch panel 3 is close, the area setting unit 8 can set the effective areas A1 and A2 in which a part of the area is repeated. At this time, the drive line drive circuit 5 selectively drives the drive line 35r11 passing only the effective area A1, the drive line 35r22 passing only the effective area A2, and the drive line 35r12 passing through both of the effective areas A1 and A2. Moreover, at this time, the touch panel controller 4 selectively processes the signals of only the sensing line 35r11 passing through the effective area A1, the sensing line 33r22 passing only the effective area A2, and the sensing line 33r12 passing through the effective areas A1 and A2. . Further, the drive lines 35r11, 35r22, 35r12, and the sense lines 33r11, 33r22, 33r12 are indicated by thick solid lines in the drawing.

In this case, a specific example of a method of driving the drive line 35 by the drive line drive circuit 5 will be described with reference to the drawings. Fig. 47 is a view showing another example of a specific driving method of the driving line of the driving line driving circuit in the second operation example. In addition, Fig. 47 assumes that the effective areas A1, A2 as shown in Fig. 46 are set.

As shown in FIG. 47, the drive line drive circuit 5 applies the above-described inherent to the drive line 35r11 passing only the effective area A1, the drive line 35r22 passing only the effective area A2, and the drive line 35r12 passing through both of the effective areas A1 and A2. Drive signal (refer to Figure 32). Further, the drive line drive circuit 5 grounds the drive lines that have not passed through any of the effective areas A1 and A2, and suppresses the same. The signal level of the drive line changes over time.

In this case, a specific operation example of the amplifying unit 71 will be described with reference to the drawings. Fig. 48 is a block diagram showing another example of the specific operation of the amplifying unit in the second operation example. Further, the amplifying portion 71 shown in Fig. 48 is the same as the amplifying portion 71 shown in Fig. 40. Further, Fig. 48 assumes that the effective areas A1, A2 as shown in Fig. 46 are set.

As shown in FIG. 48, the opening and closing switch 712 that supplies only the sensing line 33r11 of the effective area A1, the sensing line 33r22 of only the effective area A2, and the sensing line 33r12 of both the effective areas A1 and A2 is turned on. . Thereby, only the sensing line 33r11 of the effective area A1, the sensing line 33r22 passing only the effective area A2, and the respective signals of the sensing line 33r12 passing through the effective areas A1 and A2 are amplified by the amplifier 711 and output from the amplifying part 71. . On the other hand, the opening and closing switch 712 that supplies a signal that does not pass through the sensing line of any of the effective areas A1, A2 is in a non-conduction state. Thereby, the signal of the sensing line that has not passed through the effective area A is not amplified by the amplifier 711, and is not output from the amplifying portion 71.

Further, a specific operation example of the signal acquisition unit 72 in this case will be described with reference to the drawings. Fig. 49 is a block diagram showing another example of the specific operation of the selection acquisition unit in the second operation example. The signal acquisition unit 72 shown in FIG. 49 is the same as the signal acquisition unit 72 shown in FIG. In addition, FIG. 49 assumes that the effective areas A1 and A2 shown in FIG. 46 are set.

As shown in FIG. 49, the branch switch 721 can correspond to each of the sensing line 33r11 passing only the effective area A1, the sensing line 33r22 passing only the effective area A2, and the sensing line 33r12 passing through both the effective areas A1 and A2. Terminal connection Pick up. Thereby, the signal amplified by the amplifying portion 71 only through the sensing line 33r11 of the effective area A1, the signal passing only the sensing line 33r22 of the effective area A2, and the signal of the sensing line 33r12 passing through the effective areas A1 and A2, respectively Output to the back section. On the other hand, the branch switch 721 is not connected to a terminal corresponding to the sensing line that does not pass through any of the effective areas A1, A2. Thereby, the signal of the sensing line that has not passed through any of the effective areas A1, A2 is not output to the latter stage.

In this manner, even if the touch position detected on the touch panel 3 is close, the area setting unit 8 changes only the drive line to be driven or the sense line to be processed by the change in the set effective area. Therefore, the touch panel system 1r shown in FIG. 30 can be separated from the touch position even if the multi-touch in the case where the plurality of touch positions on the touch panel 3 are close to each other (refer to FIG. 38~) Figure 44) also corresponds.

As described above, in a state where a plurality of touch positions on the touch panel 3 are close to each other, the area setting unit 8 substantially sets an effective area including each touch position. Further, in a case where the plurality of touch positions on the touch panel 3 are close to each other, the area setting unit 8 may set the effective area including the touch positions, calculate the effective area information, and the like.

Moreover, regardless of whether the plurality of touch positions on the touch panel 3 are close, the area setting unit 8 can set the 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 also set an inclusive effective area including each touch position detected by the touch panel controller 4.

(4) Others

[1] Although both the amplifying unit 71 and the signal obtaining unit 72 are configured to selectively process the signal of the sensing line 33 based on the effective area information, any one of them may be selectively processed. When any of these processes is performed, power consumption can also be reduced.

[2] The operation of the drive line drive circuit 5 to selectively drive the drive line 35 (the first operation) and the operation of the touch panel controller 4 to selectively process the signal of the induction line 33 (the second operation) are simultaneously performed. But you can do any action. When performing any of these operations, it is also possible to reduce power consumption or improve the detection sensitivity of the touch operation.

[3] Although a projection type capacitive touch panel system is exemplified as an embodiment of the present invention, the present invention is only required to be of another projection type electrostatic capacitance method, a surface type electrostatic capacitance method, or an optical type. A touch panel system that can be selectively driven or selectively processed, and any type of touch panel system can be applied.

<<Transformation, etc.>>

The present invention is not limited to the embodiments of the first and second features described above, and various modifications can be made within the scope of the claims, and the first and third features of the first feature are described. Embodiments obtained by appropriately combining the disclosed technical methods are also included in the technical scope of the present invention. That is, all of the points 1 to 17 and the second feature of the first feature disclosed in the present invention are considered to be illustrative only and not intended to be limiting. The scope of the present invention is not intended to be limited to the scope of the present invention, and is intended to be included in the scope of the present invention. Within the scope.

[Industrial availability]

The invention can be applied to touch type such as television, personal computer, mobile phone, digital camera, portable game machine, electronic photo frame, portable information terminal, electronic book, home appliance product, ticket vending machine, ATM, and car navigation device. Various electronic machines. In addition, it can also be applied to large electronic devices such as a display surface of a large display device or an electronic whiteboard.

1‧‧‧Touch panel system

1a‧‧‧Touch panel system

1b‧‧‧Touch panel system

1c‧‧‧Touch panel system

1d‧‧‧Touch panel system

1e‧‧‧Touch Panel System

1f‧‧‧Touch Panel System

1g‧‧‧ touch panel system

1h‧‧‧ touch panel system

1i‧‧‧Touch Panel System

1j‧‧‧Touch Panel System

1k‧‧‧ touch panel system

1m‧‧‧ touch panel system

1n‧‧‧Touch Panel System

1o‧‧‧Touch Panel System

1r‧‧‧Touch Panel System

2‧‧‧Display device

3‧‧‧Touch panel

3a‧‧‧Touch panel

3b‧‧‧ touch panel

3c‧‧‧ touch panel

4‧‧‧Touch Panel Controller

5‧‧‧Drive line driver circuit

8‧‧‧Regional setting department

10‧‧‧Mobile Phone

31‧‧‧Main sensor (main sensor)

31a‧‧‧Main sensor group (main sensor)

31b‧‧‧Main sensor group (main sensor)

32‧‧‧Sub-sensor (sub-sensing unit)

32a‧‧‧Sub-sensor group (sub-sensing unit)

33‧‧‧Induction line

33r‧‧‧Induction line

33r1‧‧‧Induction line

33r2‧‧‧Induction line

33r3‧‧‧Induction line

33r11‧‧‧Induction line

33r12‧‧‧Induction line

33r22‧‧‧Induction line

34‧‧‧Subsense line

35‧‧‧ drive line

35r‧‧‧ drive line

35r1‧‧‧ drive line

35r2‧‧‧ drive line

35r3‧‧‧ drive line

35r11‧‧‧ drive line

35r12‧‧‧ drive line

35r22‧‧‧ drive line

41‧‧‧Decrease Department

41a‧‧‧Decrease Department

42‧‧‧Coordinate detection unit (touch detection unit)

43‧‧‧CPU

45a‧‧‧Storage Department

45b‧‧‧Storage Department

45c‧‧‧Storage Department

45d‧‧‧Storage Department

46‧‧‧Additional Department

47‧‧‧Charge integrator (decoding unit)

48‧‧‧AD conversion unit (3rd AD conversion unit, 4th AD conversion unit)

48a‧‧‧AD conversion unit (first AD conversion unit, second AD conversion unit)

49‧‧‧Differential Amplifier

50‧‧‧ Fully Differential Amplifier

51‧‧‧CPU

52‧‧‧ROM

53‧‧‧RAM

54‧‧‧ camera

55‧‧‧Microphone

56‧‧‧Speakers

57‧‧‧ operation keys

58‧‧‧Decoding Department

59‧‧‧Decision Department (Touch Detection Department)

61‧‧‧Information memory department for non-touch operation

62‧‧‧Correction Department

71‧‧‧Amplification

72‧‧‧Signal Acquisition Department

73‧‧‧AD conversion department

81‧‧‧Effective Area Calculation Department

82‧‧‧ Storage Department

100‧‧‧Communication Processing Department

101‧‧‧Filter Department

102‧‧‧Logic Reversal Department

103‧‧‧Additional Department

711‧‧Amplifier

712‧‧‧Open and close switch

721‧‧‧ branch switch

821‧‧‧ register

A‧‧‧effective area

A1‧‧‧ effective area

A2‧‧‧effective area

A3‧‧‧effective area

SW‧‧‧Opening switch

Fig. 1 is a schematic view showing the basic configuration of a touch panel system of the present invention.

2 is a flow chart showing the basic processing of the touch panel system of FIG. 1.

3(a) to (c) are diagrams showing waveforms of signals processed by the subtraction unit in the touch panel system of Fig. 1.

4 is a schematic view showing the basic configuration of another touch panel system of the present invention.

5 is a schematic diagram showing a touch panel that does not include a sub-sensor group in the touch panel system of FIG.

6 is a flow chart showing the basic processing of the touch panel system of FIG. 4.

Fig. 7 is a schematic view showing the basic configuration of still another touch panel system of the present invention.

FIG. 8 is a flow chart showing the basic processing of the touch panel system of FIG. 7.

FIG. 9 is a view showing a driving manner of a touch panel in a previous touch panel system.

FIG. 10 is a view showing a driving method (orthogonal sequence driving method) of a touch panel in the touch panel system of the present invention.

FIG. 11 is a view showing a process necessary for obtaining the same sensitivity as the touch panel of the driving method of FIG. 10 by using the touch panel of the driving method of FIG. 9.

12 is a schematic diagram showing a touch panel system of a touch panel including an orthogonal sequence driving method according to another touch panel system of the present invention.

Fig. 13 is a schematic view showing the basic configuration of still another touch panel system of the present invention.

Fig. 14 is a schematic view showing the basic configuration of still another touch panel system of the present invention.

Fig. 15 is a schematic view showing the basic configuration of still another touch panel system of the present invention.

Fig. 16 is a schematic view showing the basic configuration of still another touch panel system of the present invention.

17 is a circuit diagram showing an example of a fully differential amplifier in the touch panel system of FIG. 16.

Fig. 18 is a schematic view showing the basic configuration of still another touch panel system of the present invention.

FIG. 19 is a block diagram showing a noise processing unit provided in the touch panel system of Patent Document 1.

Fig. 20 is a schematic view showing the basic configuration of still another touch panel system of the present invention.

21 is a flow chart showing the basic processing of the touch panel system of FIG.

Fig. 22 is a schematic view showing the basic configuration of still another touch panel system of the present invention.

23 is a diagram showing the basic composition of the other touch panel system of the present invention. Schematic diagram.

Fig. 24 is a schematic view showing the basic configuration of still another touch panel system of the present invention.

Fig. 25 is a schematic view showing the basic configuration of still another touch panel system of the present invention.

Fig. 26 is a schematic view showing the basic configuration of still another touch panel system of the present invention.

Fig. 27 is a flow chart showing the basic processing of the determination unit in the touch panel system of Fig. 22.

28(a) to (c) are schematic diagrams showing the touch information identification method in the flowchart of Fig. 27.

Fig. 29 is a functional block diagram showing the configuration of a mobile phone equipped with the above touch panel system.

Fig. 30 is a schematic view showing the basic configuration of still another touch panel system of the present invention.

Figure 31 is a block diagram showing an example of an effective area.

32(a) and (b) are views showing an example of a specific driving method of the driving line of the driving line driving circuit in the first operation example.

Fig. 33 is a block diagram showing an example of a specific operation of the amplifying unit in the first operation example.

Fig. 34 is a block diagram showing an example of a specific operation of the selection acquisition unit in the first operation example.

Fig. 35 is a block diagram showing an example of a specific operation of the area setting unit in the first operation example.

Fig. 36 is a view showing an example of a method of setting an effective area in the first operation example.

Fig. 37 is a view showing another example of the method of setting the effective area in the first operation example.

38 is a block diagram showing an example of an effective area set in the touch panel in the second operation example.

Fig. 39 is a view showing an example of a specific driving method of the driving line of the driving line driving circuit in the second operation example.

Fig. 40 is a block diagram showing an example of a specific operation of the amplifying unit in the second operation example.

41 is a block diagram showing an example of a specific operation of the selection acquisition unit in the second operation example.

Fig. 42 is a flow chart showing an example of a specific operation of the area setting unit in the second operation example.

Fig. 43 is a view showing an example of a method of setting an effective area in the second operation example.

Fig. 44 is a view showing another example of the method of setting the effective area in the second operation example.

45 is a block diagram showing another example of the effective area set in the touch panel 3 in the second operation example.

Fig. 46 is a block diagram showing another example of the effective area set in the touch panel 3 in the second operation example.

Fig. 47 is a view showing another example of a method of driving the drive line of the drive line drive circuit in the second operation example.

Fig. 48 is a block diagram showing another example of the specific operation of the amplifying unit in the second operation example.

Fig. 49 is a block diagram showing another example of the specific operation of the selection acquisition unit in the second operation example.

1‧‧‧Touch panel system

2‧‧‧Display device

3‧‧‧Touch panel

4‧‧‧Touch Panel Controller

5‧‧‧Drive line driver circuit

31‧‧‧Main sensor

32‧‧‧Sub sensor

33‧‧‧Induction line

34‧‧‧Subsense line

35‧‧‧ drive line

41‧‧‧Decrease Department

42‧‧‧Coordinate detection unit (touch detection unit)

43‧‧‧CPU

Claims (24)

A touch panel system includes: a touch panel, comprising: a plurality of sensing lines and a plurality of driving lines, wherein the driving lines are disposed to intersect the sensing lines, and static electricity is formed between the sensing lines a driving line driving circuit that drives the driving line in parallel; a touch panel controller that processes the sensing line signal and generates touch information; and an area setting unit that is based on the touch information in the touch panel Setting the effective area; and the touch panel controller includes: a subtraction unit that calculates a signal difference of the sensing lines adjacent to each other; and a decoding unit that calculates a code sequence of the driving line by parallel operation, and uses the above subtraction Calculating a difference distribution of the electrostatic capacitances by calculating an inner product of the differential output sequences corresponding to the code sequence; and generating, by the touch detection unit, the touch information based on a difference distribution of the electrostatic capacitances calculated by the decoding unit The area setting unit is configured to be set in the effective area of the touch panel based on the touch information. , A new set by said effective region; and the operation of a touch panel system of at least the following: driven by the driving circuit selectively driven by the line current of the driving operation of the first line of the effective area of the set, and The second operation of the signal passing through the sensing line of the active area currently set is selectively processed by the touch panel controller. The touch panel system of claim 1, further comprising a switch for the sensing line Sn selected from the sensing line and two sensing lines adjacent to the sensing line Sn (sensing line Sn+1, sensing line Sn- 1), calculating a difference between the signal of the sensing line Sn and the signal of the sensing line Sn+1, that is, the first difference ((Sn+1)-Sn), or the signal of the sensing line Sn and the sensing line Sn-1 The signal difference is the second difference (Sn-(Sn-1)), and the signal input to the sensing line of the above-mentioned subtraction unit is switched, where n is a natural number of 2 or more. The touch panel system of claim 2, wherein the switch comprises two terminals and is configured to select one of the terminals; and the code sequence for driving the drive lines in parallel drives the first to the Mth numbers as shown below. Drive line (component 1 or -1): d ₁ = (d ₁₁ , d ₁₂ , ..., d _1N )d ₂ = (d ₂₁ , d ₂₂ ,..., d _2N )‧‧‧d _M = (d _M1 , d _M2 , ..., d _MN ), where M is an integer of 2 or more, N is a natural number, and the differential output sequence "S _j,P (j=1) corresponding to the above code sequence ,...,[L/2],P=1,2) (L is the number of sense lines, the integer part of [n]=n)" is defined as: S _j,1 : Correspondence when switch SW selects a terminal in the output sequence S _{j 1} ~ d _M of _{d, 2:} when the switch SW selects the corresponding other terminal of the output sequence d _M d ₁ ~; the decoding arithmetic unit for driving the parallel lines of the code sequence of the driving, and the above-described The code sequence corresponds to the inner product of the differential output sequence described above. The touch panel system of claim 2, wherein the subtraction unit includes a first AD conversion unit that converts the analog signal into a digital signal, and the subtraction unit uses the analog signal obtained from the sensing line by the first AD conversion unit. After converting into a digital signal, the first difference and the second difference are calculated by calculating the difference between the digital signals. The touch panel system of claim 2, wherein the subtraction unit includes a second AD conversion unit that converts the analog signal into a digital signal, and the subtraction unit calculates the difference between the analog signals obtained from the sensing line by using The second AD conversion unit converts the difference of the analog signal into a digital signal, and calculates the first difference and the second difference. The touch panel system of claim 5, wherein the subtraction unit includes a fully differential amplifier that calculates the first difference and the second difference by calculating a difference between the analog signals obtained from the sensing lines adjacent to each other. The touch panel system of claim 1, further comprising: a non-touch operation information storage unit that memorizes a difference distribution of the electrostatic capacitance calculated by the decoding unit during a non-touch operation; and a correction unit The difference distribution of the electrostatic capacitance calculated by the decoding unit during the touch operation is subtracted from the difference between the electrostatic capacitances stored in the non-touch operation in the information storage unit during the non-touch operation cloth. The touch panel system of claim 1, wherein the touch detection unit determines whether the touch operation is based on a difference between the sense line signals adjacent to each other calculated by the subtraction unit and a positive and negative threshold value. . The touch panel system of claim 8, wherein the touch detection unit creates a difference between the electrostatic capacitance based on a difference between a sense line signal adjacent to each other calculated by the subtraction unit and a positive and negative threshold value. The three-valued increase and decrease table is distributed, and the increase/decrease table is converted into a binary image to generate the touch information. The touch panel system of claim 1, wherein the driving line driving circuit applies the inherent code sequence set for each of the driving lines to each of the driving lines passing through the effective area, and the above-mentioned code sequence that does not pass the effective area Each of the drive lines is not assigned the above code sequence. The touch panel system of claim 1, wherein the touch panel controller further comprises an amplifying portion that selectively amplifies a signal passing through the sensing line of the active area. The touch panel system of claim 1, wherein the touch panel controller further includes a signal acquisition unit that selectively acquires the sensing line signal passing through the effective area and outputs the time division. The touch panel system of claim 1, wherein the area setting unit sets a new effective area including a touch position of the touch information. The touch panel system of claim 1, wherein the area setting unit sets one of the touch information, that is, the touch position, and the moving speed The new effective area mentioned above should be the size. The touch panel system of claim 1, wherein the area setting unit sets the new effective area that is the entire surface of the touch panel when the touch panel controller does not detect the touch operation. The touch panel system of claim 1, wherein when the first mode is selected, the area setting unit sets a new effective area based on a touch position of the touch information, and when the second mode is selected, the area setting The part continuously sets the new effective area as the entire surface of the touch panel. In the touch panel system of claim 1, wherein the touch information includes a plurality of touch positions, the area setting unit sets a new effective area based on the plurality of touch positions. In the touch panel system of claim 17, wherein the area setting unit sets a new effective area based on the plurality of touch positions, a plurality of new valid areas corresponding to the touch positions are respectively set. The touch panel system of claim 18, wherein the number of the new effective areas set by the area setting unit is set to an upper limit value. The touch panel system of claim 17, wherein the area setting unit sets the new effective area that is the entire surface of the touch panel at each specific timing. The touch panel system of claim 1, wherein the code sequence is an orthogonal sequence or an M sequence. The touch panel system of claim 1, which further comprises a display device, and The touch panel is disposed on a front surface of the display device. The touch panel system of claim 22, wherein the display device is a liquid crystal display, a plasma display, or an organic EL display, a field emission display. A touch panel type electronic device characterized by comprising the touch panel system according to any one of claims 1 to 23.