JP2013206206A - Touch panel system, electronic information device, and method for manufacturing touch panel system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a touch panel system capable of accurately detecting an indication body independently of a display device to which the touch panel system is applied, an electronic information device including the touch panel system, and a method for manufacturing the touch panel system.SOLUTION: A touch panel system 1 includes: a touch panel 10 that is provided on a display surface of a display device X and outputs a response signal corresponding to an indication body on the surface; a touch panel controller 20 that drives the touch panel 10 and acquires a response signal Ss output from the touch panel 10; and a storage unit 50 that stores a drive start timing parameter P therein. The display device X operates in synchronization with a reference signal H whose signal level makes a predetermined change in a predetermined cycle. After the signal level of the reference signal H makes the predetermined change, the touch panel controller 20 drives the touch panel 10 at timing when a period corresponding to the drive start timing parameter P elapses.

Description

  The present invention relates to a touch panel system including a touch panel provided on a display surface of a display device, an electronic information device including the touch panel system, and a method for manufacturing the touch panel system.

  2. Description of the Related Art In recent years, touch panel systems that accept user instructions by detecting the presence and position of an indicator (for example, a user's finger or stylus, the same applies hereinafter) that touches or approaches the surface have become electronic devices such as mobile phones and personal computers. Increasingly mounted on information equipment.

  In many cases, the touch panel system is provided on the display surface of the display device, but the detection accuracy of the indicator may be reduced due to noise generated by the display device. For example, in a liquid crystal display, it is necessary to invert the polarity of the voltage applied to the liquid crystal in order to prevent burn-in of the liquid crystal material. When the polarity is inverted by inverting the voltage applied to the common electrode, the polarity of the voltage is Noise is generated at the timing of inversion. Further, when this polarity inversion is performed for each display of one line, noise frequently occurs.

  Therefore, in Patent Document 1, a pulsed mask signal is generated in synchronization with the polarity inversion period of the voltage applied to the common electrode, and the touch panel drive is stopped during the period from the rising edge to the falling edge of the mask signal. Thus, there has been proposed a touch panel system that detects the indicator while avoiding the timing at which the liquid crystal display generates noise.

  Further, in Patent Document 2, in a touch panel system including a pressure-sensitive touch panel, a liquid crystal display generates noise by inputting a coordinate detection signal of the touch panel to a controller in synchronization with a stable portion of an alternating signal applied to liquid crystal. There has been proposed a touch panel system that detects an indicator while avoiding the generation timing.

JP2011-1000018 A Japanese Patent Laid-Open No. 06-318137

  However, with the diversification of types of display devices (for example, plasma displays and organic EL (electroluminescence) displays in addition to liquid crystal displays) and sizes, the patterns of noise resulting from the operation of the display devices are also diversified. Therefore, even in the touch panel system proposed in Patent Document 1 and Patent Document 2 that detects the indicator by avoiding the timing of polarity inversion of the voltage applied to the liquid crystal display, avoid noise caused by the operation of the display device. It may be difficult to detect the indicator.

  Specifically, for example, as the size of the liquid crystal display increases, the delay from when the polarity of the voltage applied to the liquid crystal display is reversed until noise is generated increases. Therefore, even if the touch panel system proposed in Patent Document 1 and Patent Document 2 is applied to a large liquid crystal display, the indicator is detected while avoiding noise caused by the polarity inversion of the voltage applied to the liquid crystal display. Can be difficult.

  Therefore, the present invention provides a touch panel system that can accurately detect an indicator without depending on a display device to be applied, an electronic information device including the touch panel system, and a method for manufacturing the touch panel system.

  In order to achieve the above object, the present invention provides a touch panel that is provided on a display surface of a display device and outputs a response signal corresponding to the presence or absence of an indicator that is in contact with or close to the surface and the position of the indicator, A touch panel controller for driving the touch panel to obtain the response signal output from the touch panel; and a storage unit for storing a drive start timing parameter, wherein the display device has a predetermined signal level at a predetermined cycle. The touch panel controller operates in synchronization with the changing reference signal, and the touch panel controller drives the touch panel at a timing when a period corresponding to the driving start timing parameter has elapsed after a predetermined change in the signal level of the reference signal. Provided is a touch panel system.

  According to this touch panel system, the timing at which the touch panel controller drives the touch panel to acquire the response signal can be arbitrarily determined by the drive start timing parameter stored in the storage unit.

  Furthermore, in the touch panel system having the above characteristics, the timing at which the touch panel controller acquires the response signal is from when the signal level of the reference signal changes to a predetermined change until the next predetermined change. It is preferable that the drive start timing parameter is determined so as to correspond to a period in which the level of noise generated by the apparatus is relatively small.

  According to this touch panel system, a period during which the level of noise generated by the display device is relatively high during a period from when the signal level of the reference signal changes to the next predetermined change is avoided. The touch panel controller can acquire the response signal during a period when the noise level is relatively small. Therefore, it is possible to detect the indicator with high accuracy.

Furthermore, in the touch panel system having the above characteristics, the touch panel controller includes:
A drive unit that provides a drive signal to the touch panel and drives the touch panel to output the response signal; a reception unit that acquires the response signal; and a transmission / reception control unit that controls operations of the transmission unit and the reception unit; The transmission / reception control unit preferably controls timing when the transmission unit gives the drive signal to the touch panel and timing when the reception unit acquires the response signal.

  According to this touch panel system, it is possible to arbitrarily determine the operation timings of the transmission unit that supplies the drive signal to the touch panel and the reception unit that acquires the response signal from the touch panel.

  Furthermore, in the touch panel system having the above characteristics, the transmission unit provides the drive signal to the touch panel at a timing when a period corresponding to the drive start timing parameter has elapsed after the signal level of the reference signal has changed a predetermined amount. As described above, after the transmission / reception control unit controls the transmission unit, the signal level of the reference signal changes a predetermined amount, and a period corresponding to the drive start timing parameter elapses, and then a predetermined period elapses. Therefore, it is preferable that the transmission / reception control unit controls the receiving unit so that the receiving unit acquires the response signal.

  According to this touch panel system, after the transmission unit gives a drive signal to the touch panel, the reception unit can acquire a response signal output from the touch panel that has been in a stable state after a predetermined period has elapsed. .

  Further, the touch panel system according to the above feature further includes a drive start signal generation unit that supplies the drive start signal generated based on the reference signal and the drive start timing parameter to the transmission / reception control unit, and the drive start signal generation The unit generates the drive start signal having a predetermined signal level change at a timing when a period corresponding to the drive start timing parameter has elapsed after the signal level of the reference signal has changed a predetermined level, and the transmission / reception control The control unit controls the transmission unit to apply the drive signal to the touch panel at a timing at which the signal level of the drive start signal changes to a predetermined level, and after the signal level of the drive start signal changes to a predetermined level If the receiving unit is controlled to acquire the response signal at the timing when the predetermined period has elapsed, Arbitrariness.

  According to this touch panel system, it is possible to arbitrarily determine the operation timing of the transmission unit and the reception unit only by providing the drive start signal generation unit that generates the drive start signal based on the reference signal and the drive start timing parameter. It becomes possible.

  Further, the touch panel system according to the above feature further includes a drive timing determination unit that determines the drive start timing parameter and stores the drive start timing parameter in the storage unit, wherein the drive timing determination unit is configured such that the touch panel controller transmits the signal of the reference signal. A level of noise included in each of the response signals obtained by driving the touch panel at a plurality of different timings based on a timing at which the level changes to a predetermined level is calculated, and the touch panel controller receives the response signal The driving is performed so that the timing at which the signal level of the reference signal is changed from a predetermined change to the next predetermined change and corresponds to a period in which the noise level is relatively small. When the start timing parameter is determined and stored in the storage unit, Masui.

  According to this touch panel system, the drive timing parameter for detecting the indicator with high accuracy can be automatically determined by providing the drive timing determination unit.

  Furthermore, in the touch panel system having the above characteristics, the reference signal may be a horizontal synchronization signal.

  The present invention also provides an electronic information device comprising the touch panel system having the above characteristics and the display device.

  Further, the present invention provides a touch panel system manufacturing method according to the above feature, wherein a noise measurement step of measuring a level of noise generated by the display device and a timing at which the touch panel controller acquires the response signal are the reference. The drive start timing parameter is determined so as to correspond to a period from when the signal level of the signal changes to a predetermined change until the next change and the level of the noise is relatively small. And a drive start timing parameter determination step to be stored in a storage unit.

  According to this method for manufacturing a touch panel system, a period in which the level of noise generated by the display device is relatively high during a period from when the signal level of the reference signal changes to a predetermined change. Thus, it is possible to manufacture a touch panel system in which the touch panel controller acquires a response signal during a period when the noise level is relatively small. Therefore, it is possible to manufacture a touch panel system that can detect the indicator with high accuracy.

  According to the touch panel system having the above characteristics, it is possible to arbitrarily determine the timing at which the touch panel controller drives the touch panel to acquire the response signal. Therefore, the timing for acquiring the response signal can be determined according to the pattern of noise generated by the display device. Therefore, the touch panel system having the above characteristics can accurately detect the indicator without depending on the applied display device.

  Furthermore, in the touch panel system having the above characteristics, the timing at which the touch panel controller drives the touch panel to acquire the response signal can be arbitrarily determined independently of the operation timing of the display device. Therefore, the relative timing of each operation in the touch panel controller can be set to an optimum timing regardless of the noise pattern generated by the display device.

The block diagram which shows the structural example of the touchscreen system which concerns on 1st Embodiment of this invention. The block diagram shown about the structural example of the touch panel shown in FIG. 4 is a timing chart showing an operation example of the touch panel controller shown in FIG. 1. The timing chart shown about the operation example of the drive start signal production | generation part shown in FIG. 1, and a touchscreen controller. The block diagram shown about the structural example of the drive start signal production | generation part shown in FIG. 6 is a timing chart illustrating an operation example of the shift register illustrated in FIG. 5. The block diagram which shows the structural example of the touchscreen system which concerns on 2nd Embodiment of this invention. 8 is a flowchart illustrating an operation example of a drive timing determination unit illustrated in FIG. 7. The graph shown about an example of the measurement result of the noise maximum value for every flame | frame. The block diagram which shows the structural example of the electronic information apparatus which concerns on embodiment of this invention.

<< Touch panel system >>
Hereinafter, a touch panel system according to an embodiment of the present invention will be described. In the following, for concrete description, a touch panel system including a capacitive and projection touch panel and applied to a liquid crystal display is illustrated.

<First Embodiment>
A touch panel system according to a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram illustrating a configuration example of a touch panel system according to the first embodiment of the present invention. FIG. 2 is a block diagram showing a configuration example of the touch panel shown in FIG.

  As shown in FIG. 1, the touch panel system 1 provides a response signal Ss corresponding to the presence / absence of an indicator that is provided on the display surface of the display device (liquid crystal display) X and that is in contact with or close to the surface and the position of the indicator. The touch panel 10 to be output, the touch panel controller 20 that generates the output signal Sc by obtaining the response signal Ss output from the touch panel 10 while driving the touch panel 10 with the drive signal Sd, and the output signal output by the touch panel controller 20 A position calculation unit 30 that calculates the presence / absence of an indicator that touches or approaches the surface of the touch panel 10 based on Sc and a position of the indicator, a horizontal synchronization signal H that is output from the display device driver Y, and a drive start timing parameter A drive start signal generator 40 for generating a drive start signal Cst based on P; Comprising a moving start timing parameter P and a storage unit 50 for storing the drive in the timing parameters U, the.

  As shown in FIG. 2, the touch panel 10 is provided on the display surface X1 of the display device X, and displays the same as the plurality of drive lines DL arranged in parallel to each other along the display surface X1 of the display device X. A plurality of sense lines SL arranged in parallel with each other along the display surface X1 of the device X. The direction in which the drive line DL extends (the horizontal direction in the figure) and the direction in which the sense line SL extends (the vertical direction in the figure) are different and intersect (in the example shown in FIG. 2, they are orthogonal). However, the drive line DL and the sense line SL are provided with an insulating transparent substrate or the like, and intersect with each other. The drive line DL and the sense line SL may be disposed on the display surface X1 of the display device X, or may be disposed so as to be embedded in the surface of the display surface X1 of the display device X.

  When the indicator contacts or approaches the surface of the touch panel 10 being driven, the capacitance at the intersection of the drive line DL and the sense line SL changes. In the touch panel system 1, the indicator is detected using the fact that the response signal Ss indicating the change in capacitance appears on the sense line SL.

  Specifically, for example, a series signal composed of pseudo-random numbers such as an M series (for example, a signal having the same number of digits as the number of drive lines DL and combining “0” and “1”) is used as each drive signal Sd. The magnitude of the capacitance at each position on the surface of the touch panel 10 is shown by performing simultaneous decoding on the response signal Ss appearing on each sense line SL and applying the series signal to the drive line DL. An output signal Sc is generated. The drive signal Sd of the series signal given to each drive line DL is updated every predetermined period.

  As shown in FIG. 1, the touch panel controller 20 generates a drive signal Sd and outputs a transmission unit 21, a reception unit 22 that acquires a response signal Ss, and a drive signal Sd generated by the transmission unit 21. 10, a transmission side interface 23 that is applied to the drive line DL, a reception side interface 24 that supplies the response signal Ss output from the touch panel 10 to the reception unit 22, and a transmission / reception control unit 25 that controls the operations of the transmission unit 21 and the reception unit 22. .

  The transmission unit 21 includes a drive signal generation unit 211 that generates the above-described drive signal Sd. The timing at which the drive signal generation unit 211 generates the drive signal Sd is controlled by the transmission / reception control unit 25.

  The reception unit 22 includes an amplifier unit 221 that amplifies the response signal Ss, a sample hold unit 222 that acquires (samples and holds) the response signal Sa amplified by the amplifier unit 221, and a response signal Ssh acquired by the sample hold unit 222 The AD conversion unit 223 for AD (Analog to Digital) conversion and the response signal Sds AD-converted by the AD conversion unit 223 using the decoding signal Se composed of the above-described series signal provided from the drive signal generation unit 211 And a decoding unit 224 that generates the output signal Sc. Note that the decoding unit 224 may generate the decoding signal Se by itself without receiving the decoding signal Se generated by the drive signal generation unit 211.

  The operations of the amplifier unit 221, the sample hold unit 222, the AD conversion unit 223, and the decoding unit 224 are controlled by the transmission / reception control unit 25. In particular, the timing at which the sample hold unit 222 acquires the response signal Sa is controlled by the sample hold timing control signal Csh output by the transmission / reception control unit 25.

  The transmission / reception control unit 25 controls the transmission unit 21 and the reception unit 22 based on the drive start signal Cst generated by the drive start signal generation unit 40 and the driving timing parameter U stored in the storage unit 50. .

  The drive start signal generation unit 40 generates the drive start signal Cst based on the horizontal synchronization signal H (reference signal) generated by the display device drive unit Y and the drive start timing parameter P stored in the storage unit 50. It is generated and given to the transmission / reception control unit 25. The display device X operates in synchronization with the horizontal synchronization signal H (displays one line).

  The storage unit 50 includes a first register 51 that stores a driving start timing parameter P, and a second register 52 that stores a driving timing parameter U. Note that each of the first register 51 and the second register 52 may be configured by, for example, a 4-bit nonvolatile register.

  Next, an operation example of the touch panel controller 20 will be described with reference to FIG. FIG. 3 is a timing chart showing an operation example of the touch panel controller shown in FIG.

  As shown in FIG. 3, the touch panel controller 20 drives the touch panel 10 at a timing when the drive start signal Cst rises from low to high (the signal level changes a predetermined amount). Specifically, when the drive start signal Cst rises from low to high, the transmission / reception control unit 25 performs control so that the drive signal generation unit 211 generates a new drive signal Sd and gives it to the touch panel 10.

  The drive signal generation unit 211 outputs the drive signal Sd during the period from when the drive start signal Cst rises from low to high until the next rise from low to high (drive period Td). The drive signal Sd is, for example, the above-described series signal and a value opposite to the series signal (“1” if the series signal is “0”, “0” if the series signal is “1”). And a reset signal in succession. A predetermined period (reset period T1) in the first half of the drive signal Sd is a reset signal, and a subsequent period (indicator detection period T2) is a series signal. As described above, by providing the reset period T1 before the indicator detection period T2, it is possible to prevent the charge accumulated in the previous drive period Td from affecting the current drive period Td.

  However, when the drive signal Sd is applied to the touch panel 10, the response signal Sa immediately after the transition from the reset period T1 to the indicator detection period T2 is output in a state where the charge accumulated in the touch panel 10 is not stable. Is. Therefore, after the transition from the reset period T1 to the indicator detection period T2, the transmission / reception control unit 25 causes the sample hold unit 222 to respond to the response signal Sa at a timing when a predetermined period has elapsed and the charge accumulated in the touch panel 10 has stabilized. Control to get.

  After the drive start signal Cst rises from low to high, the transmission / reception control unit 25 falls from high to low (signal level is predetermined) at a timing when a period longer than the reset period T1 (sample hold standby period T3) has elapsed. A sample hold timing control signal Csh is generated and output. Then, the sample hold unit 222 acquires the response signal Sa at the timing when the sample hold timing control signal Csh falls from high to low.

  The transmission / reception control unit 25 determines the sample hold standby period T3 based on the driving timing parameter U. Therefore, if the driving timing parameter U stored in the second register 52 is changed, the length of the sample hold standby period T3 can be changed.

  Next, operation examples of the drive start signal generation unit 40 and the touch panel controller 20 will be described with reference to FIG. FIG. 4 is a timing chart showing an operation example of the drive start signal generator and the touch panel controller shown in FIG.

  As shown in FIG. 4, the signal level of the horizontal synchronizing signal H generated by the display device driving unit Y rises from low to high at a predetermined cycle (the signal level changes predetermined). Further, the level of noise N (noise appearing on the sense line SL due to the operation of the display device X) generated by the display device X operating in synchronization with the timing when the horizontal synchronization signal H rises from low to high is also determined by the horizontal synchronization signal H. It fluctuates with the same period as the period rising from low to high. That is, during the period from when the horizontal synchronization signal H rises from low to high until the next rise from low to high, a period during which the level of the noise N generated by the display device X is relatively high, and the level of the noise N Are relatively small periods, and these periods are repeated with the same period as the period when the horizontal synchronizing signal H rises from low to high.

  After the horizontal synchronization signal H rises from low to high, the drive start signal generation unit 40 rises from the low to high signal level at the timing when the period corresponding to the drive start timing parameter P (drive start standby period Ts) has elapsed. A drive start signal Cst is generated. Accordingly, the timing at which the sample hold unit 222 acquires the response signal Sa (the timing at which the drive start standby period Ts and the sample hold standby period T3 have elapsed after the horizontal synchronization signal H rises from low to high) is set to the first register. The drive start timing parameter P stored in 51 can be arbitrarily determined.

  In particular, in the touch panel system 1 of the present embodiment, the level of the noise N generated by the display device X is relatively high between the time when the horizontal synchronization signal H rises from low to high and then rises from low to high. The first register 51 stores the drive start timing parameter P determined so that the sample hold unit 222 acquires the response signal Sa during a period in which the noise N level is relatively small.

  For example, before shipping an electronic information device including the touch panel system 1 and the display device X, a noise N generated by the display device X is measured to determine a drive start timing parameter P that satisfies the above condition, and the first register 51 is stored. In addition, after the electronic information device is shipped, for example, a user or a service person executes a predetermined application or uses a predetermined device, whereby the drive start timing parameter stored in the first register 51 is stored. P may be changed.

  A configuration example and an operation example of the drive start signal generation unit 40 capable of performing the above-described operation will be described with reference to FIGS. 5 and 6. FIG. 5 is a block diagram illustrating a configuration example of the drive start signal generation unit illustrated in FIG. 1. FIG. 6 is a timing chart showing an operation example of the shift register shown in FIG.

  As shown in FIG. 5, the drive start signal generator 40 includes four input terminals D1 to D4 and 16 to which a 4-bit drive start timing parameter P output from the output terminals R1 to R4 of the first register 51 is input. A decoder 41 having output terminals S1 to S16, a shift register 42 having an input terminal HD to which a horizontal synchronization signal H is input, an input terminal CK to which a clock signal is input, and 16 output terminals Q1 to Q16. And 16 switches 431 to 4316.

  In the switch 431, one contact is connected to the output terminal Q1, and the connection between one contact and the other contact is controlled by a signal output from the output terminal S16. In the switch 432, one contact is connected to the output terminal Q2, and the connection between one contact and the other contact is controlled by a signal output from the output terminal S15. In the switch 433, one contact is connected to the output terminal Q3, and the connection between one contact and the other contact is controlled by a signal output from the output terminal S14. In the switch 434, one contact is connected to the output terminal Q4, and the connection between one contact and the other contact is controlled by a signal output from the output terminal S13. In the switch 435, one contact is connected to the output terminal Q5, and the connection between one contact and the other contact is controlled by a signal output from the output terminal S12. In the switch 436, one contact is connected to the output terminal Q6, and the connection between one contact and the other contact is controlled by a signal output from the output terminal S11. In the switch 437, one contact is connected to the output terminal Q7, and the connection between one contact and the other contact is controlled by a signal output from the output terminal S10. In the switch 438, one contact is connected to the output terminal Q8, and the connection between one contact and the other contact is controlled by a signal output from the output terminal S9. In the switch 439, one contact is connected to the output terminal Q9, and the connection between one contact and the other contact is controlled by a signal output from the output terminal S8. In the switch 4310, one contact is connected to the output terminal Q10, and the connection between one contact and the other contact is controlled by a signal output from the output terminal S7. In the switch 4311, one contact is connected to the output terminal Q11, and the connection between one contact and the other contact is controlled by a signal output from the output terminal S6. In the switch 4312, one contact is connected to the output terminal Q12, and the connection between one contact and the other contact is controlled by a signal output from the output terminal S5. In the switch 4313, one contact is connected to the output terminal Q13, and the connection between one contact and the other contact is controlled by a signal output from the output terminal S4. In the switch 4314, one contact is connected to the output terminal Q14, and the connection between one contact and the other contact is controlled by a signal output from the output terminal S3. In the switch 4315, one contact is connected to the output terminal Q15, and the connection between one contact and the other contact is controlled by a signal output from the output terminal S2. In the switch 4316, one contact is connected to the output terminal Q16, and the connection between one contact and the other contact is controlled by a signal output from the output terminal S1. The other contacts of the switches 431 to 4316 are connected to each other, and a drive start signal Cst is output from the connection node.

  The decoder 41 makes one of the signals output from the output terminals S1 to S16 high and makes all the others low according to the drive start timing parameter P input to the input terminals D1 to D4. . As a result, any one of the switches 431 to 4316 is turned on, and all the others are turned off. That is, a signal output via any one of the switches 431 to 4316 that are turned on is the drive start signal Cst.

  Further, as shown in FIG. 6, when the horizontal synchronizing signal H input to the input terminal HD rises from low to high, the output terminal is synchronized with the rise of the clock signal input to the input terminal CK from low to high. The signal output from Q1 rises from low to high. When the clock signal input to the input terminal CK next rises from low to high, the signal output from the output terminal Q2 rises from low to high, and the signal output from the output terminal Q1 changes from high to low. Fall down.

  Similarly, every time the clock signal input to the input terminal CK rises from low to high, the signal output in the order of the output terminals Q3, Q4,..., Q16 rises from low to high, and the output terminal Q2 , Q3,..., Q16, the signals output in this order fall from high to low. That is, the signal level of the output signal changes with a time difference in the order of the output terminals Q1, Q2,.

  As described above, when any one of the switches 431 to 4316 is turned on and the signal level of the signal output from the output terminals Q1, Q2,. The timing at which the drive start signal Cst rises from low to high can be determined depending on which of 4316 is turned on (what value the drive timing parameter P is set to).

  Specifically, for example, as shown in FIG. 6, when the horizontal synchronizing signal H input to the input terminal HD rises from low to high and at the same time the clock signal falls from high to low, Assume that the frequency of the input clock signal is 2 MHz (period 0.5 μs). In this case, if the switch 431 is on (the signal output from the output terminal S16 is high), the drive start signal is 0.25 μs after the horizontal synchronization signal H input to the input terminal HD rises from low to high. Cst rises from low to high. When the switch 432 is on (the signal output from the output terminal S15 is high), the drive start signal Cst is 0.75 μs after the horizontal synchronizing signal H input to the input terminal HD rises from low to high. Rises from low to high.

  Similarly, when the switch 433 is turned on (the signal output from the output terminal S14 is high) after the horizontal synchronization signal H input to the input terminal HD rises from low to high, the switch is switched after 1.25 μs. When 434 is on (the signal output from the output terminal S13 is high), after 1.75 μs, when the switch 435 is on (the signal output from the output terminal S12 is high), after 2.25 μs, the switch When 436 is on (the signal output from the output terminal S11 is high), after 2.75 μs, when the switch 437 is on (the signal output from the output terminal S10 is high), after 3.25 μs, the switch When 438 is on (the signal output from the output terminal S9 is high), the switch 439 is turned on (from the output terminal S8) after 3.75 μs. When the output signal is high), the switch 4311 is turned on (from the output terminal S6) after 4.25 μs, and when the switch 4310 is turned on (the signal output from the output terminal S7 is high), 4.75 μs later. If the output signal is high), the switch 4313 is turned on (from the output terminal S4) after 5.25 μs, and the switch 4312 is turned on (the signal outputted from the output terminal S5 is high). When the output signal is high), the switch 4315 is turned on (from the output terminal S2) after 6.25 μs, and when the switch 4314 is turned on (the signal output from the output terminal S3 is high), 6.75 μs later. When the output signal is high), the switch 4316 is turned on (the signal output from the output terminal S1 is high) after 7.25 μs. In this case, the driving start signal Cst rises from low to high after 7.75 μs.

  In this case, if the period of the horizontal synchronization signal H is 14.7 μs, the timing at which the drive start signal Cst rises from low to high can be delayed beyond the midpoint of the period of the horizontal synchronization signal H.

  As described above, in the touch panel system 1, it is possible to arbitrarily determine the timing at which the touch panel controller 20 drives the touch panel 10 to acquire the response signal Sa. Therefore, the timing for acquiring the response signal Sa can be determined according to the pattern of the noise N generated by the display device X. Therefore, the touch panel system 1 can accurately detect the indicator without depending on the display device X to be applied.

  Furthermore, in the touch panel system 1, the timing at which the touch panel controller 20 drives the touch panel 10 to acquire the response signal Sa can be arbitrarily determined independently of the operation timing of the display device X. Therefore, the relative timing of each operation in the touch panel controller 20 can be set to an optimum timing regardless of the pattern of the noise N generated by the display device X.

Second Embodiment
Next, a touch panel system according to a second embodiment of the present invention will be described with reference to the drawings. FIG. 7 is a block diagram showing a configuration example of a touch panel system according to the second embodiment of the present invention, and corresponds to FIG. 1 shown for the first embodiment. Note that, in the touch panel system 1A according to the second embodiment of the present invention, portions that are the same as those of the touch panel system 1 according to the first embodiment of the present invention are denoted by the same reference numerals and detailed description thereof is omitted.

  As illustrated in FIG. 7, the touch panel system 1 </ b> A includes a touch panel 10, a touch panel controller 20, a position calculation unit 30, a drive start signal generation unit 40, a storage unit 50, and a horizontal output output from the display device drive unit Y. A drive timing determination unit 60 that determines a drive start timing parameter P stored in the first register 51 based on the synchronization signal H and the output signal Sc output from the touch panel controller 20. That is, the touch panel system 1A according to the second embodiment of the present invention has the same configuration as the touch panel system 1 according to the first embodiment of the present invention, except that the drive timing determination unit 60 is provided.

  An example of the operation of the drive timing determination unit 60 will be described with reference to FIG. FIG. 8 is a flowchart showing an operation example of the drive timing determination unit shown in FIG. Note that the operation shown in FIG. 8 is performed, for example, before shipment of an electronic information device including the touch panel system 1A and the display device X or at the time of calibration after shipment, and there is an indicator on the surface of the touch panel 10. It should be done in a state that does not.

  As shown in FIG. 8, the drive timing determination unit 60 first sets the provisional drive timing parameter V to an initial value of 0 and stores it in the first register 51 (step # 1). The drive timing determination unit 60 sets the number of measurement frames F to an initial value of 1 (step # 2). Then, the touch panel controller 20 gives the drive signal Sd to the touch panel 10 for driving, and acquires the response signal Ss from the touch panel 10 (see the description of the operation example of the touch panel system 1 described above).

  Next, the drive timing determination unit 60 calculates a noise evaluation value N (V, F) based on the output signal Sc output from the touch panel controller 20 (step # 3). As described above, the output signal Sc is obtained in a state where there is no indicator on the surface of the touch panel 10. Therefore, if the display device X does not generate noise, the size of the electrostatic capacitance at each position on the surface of the touch panel 10 indicated by the output signal Sc should be constant. It can be said that X represents the level of noise generated. Therefore, for example, the standard deviation of the magnitude of the capacitance at each position on the surface of the touch panel 10 indicated by the output signal Sc can be set as the noise evaluation value N (V, F).

When the noise evaluation value N (V, F) is the same provisional drive timing parameter V and is larger than the maximum noise value N _MAX (V) for each frame obtained in the previous measurement frame (0 to F-1) ( In step # 4, YES), the per-frame noise maximum value N _MAX (V) is updated to the noise evaluation value N (V, F) (step # 5). On the other hand, when the noise evaluation value N (V, F) is the same provisional drive timing parameter V and is equal to or less than the frame-by-frame noise maximum value N _MAX (V) obtained in the previous frame (0 to F-1). (Step # 4, NO), the per-frame noise maximum value N _MAX (V) is maintained without being updated. When the measurement frame F has an initial value of 1, the noise evaluation value N (V, 1) is set as the noise per frame maximum value N _MAX (V).

Next, the drive timing determination unit 60 increases the number of measurement frames F by 1 (step # 6), and confirms whether or not the number of measurement frames F has become larger than the upper limit value _FEND (step # 7). When the number of measurement frames F is less than or equal to the upper limit value F _END (step # 7, NO), the above-described operations of steps # 3 to # 6 are performed once again. On the other hand, when the number of measurement frames F is larger than the upper limit value F _END (step # 7, YES), the per-frame noise maximum value N _MAX (V) is provisional in the previous provisional drive timing parameter (0 to V-1). It is confirmed whether or not it is smaller than the noise minimum value _{NMIN for} each drive timing parameter (step # 8).

When the noise maximum value N _MAX (V) for each frame is smaller than the noise minimum value N _{MIN for} each provisional driving timing parameter in the previous provisional driving timing parameter (0 to V-1) (step # 8, YES), provisional driving is performed. The noise minimum value N _MIN for each timing parameter is updated to the noise maximum value N _MAX (V) for each frame, and the noise minimized provisional drive timing parameter V _MIN is updated to the provisional drive timing parameter V (step # 9). On the other hand, when the maximum noise value N _MAX (V) for each frame is equal to or _larger than the minimum noise value N _{MIN for} each temporary drive timing parameter in the previous temporary drive timing parameter (0 to V-1) (step # 8, NO). The noise minimum value N _{MIN for} each temporary drive timing parameter and the noise minimized temporary drive timing parameter V _MIN are maintained without being updated. When the provisional drive timing parameter V is an initial value of 0, the noise maximum value N _MAX (0) for each frame is set as the noise minimum value N _{MIN for} each provisional drive timing parameter.

Next, the drive timing determination unit 60 increases the provisional drive timing parameter V by 1 (step # 10), and confirms whether or not the provisional drive timing parameter V has become larger than the upper limit value V _END (step # 11). ). When the provisional drive timing parameter V is equal to or lower than the upper limit value V _END (step # 11, NO), the above-described operations of steps # 2 to # 10 are performed once again. On the other hand, when the provisional drive timing parameter V is larger than the upper limit value V _END (step # 11, YES), the noise minimization provisional drive timing parameter V _MIN is determined as the drive timing parameter P and is stored in the first register 51. Store it and finish the operation.

Here, an example of the measurement result of the noise maximum value N _MAX (V) for each frame will be described with reference to FIG. FIG. 9 is a graph showing an example of the measurement result of the noise maximum value for each frame. In the graph shown in FIG. 9, the horizontal axis represents the provisional drive timing parameter V, and the vertical axis represents the maximum noise value N _MAX (V) for each frame.

As shown in FIG. 9, for each provisional drive timing parameter V, a frame-by-frame noise maximum value N _MAX (V) is obtained. Then, the minimum value of the obtained noise maximum value N _MAX (V) for each frame becomes the noise minimum value N _{MIN for} each provisional drive timing parameter (▲ in the figure). Then, the provisional drive timing parameter V for which the noise minimum value N _{MIN for} each provisional drive timing parameter is obtained becomes the noise minimized provisional drive timing parameter V _MIN .

  As described above, the touch panel system 1A includes the drive timing determination unit 60, so that the drive timing parameter P for accurately detecting the indicator can be determined automatically.

  Therefore, for example, the drive start timing parameter P can be easily determined before shipment of an electronic information device including the touch panel system 1A and the display device X. In addition, for example, after the electronic information device including the touch panel system 1A and the display device X is shipped, even a user or service person who does not have special knowledge or technology can easily determine or reconfigure the drive start timing parameter P. It becomes possible to decide.

Note that it is preferable that the upper limit value F _END of the number of measurement frames F be a certain large value, for example, 64. In this case, the drive timing determination unit 60 automatically determines the drive timing parameter P that enables the sample hold unit 222 to acquire the response signal Sa at the timing when the noise level continuously decreases and becomes low. It becomes possible to do.

<< Electronic Information Equipment >>
A configuration example of the electronic information device according to the embodiment of the present invention including the touch panel systems 1 and 1A and the display device X will be described with reference to FIG. FIG. 10 is a block diagram illustrating a configuration example of the electronic information device according to the embodiment of the present invention.

  As shown in FIG. 10, an electronic information device 100 according to an embodiment of the present invention includes a display device 101 corresponding to the above-described display device X, a display device control unit 102 including the above-described display device driving unit Y, and the above-described display device. A touch panel 103 corresponding to the touch panel 10, a touch panel controller 104 corresponding to the touch panel controller 20, a button switch unit 105 that receives a user instruction when pressed by the user, and an imaging unit that generates image data by imaging. 106, a sound output unit 107 that outputs input sound data as sound, a sound collecting unit 108 that generates sound data by collecting sound, and processing of sound data to be given to the sound output unit 107 and the sound collecting unit 108 A voice processor 109 for processing the received voice data; A wireless communication unit 110 that wirelessly communicates data, an antenna 111 that radiates communication data as electromagnetic waves and receives electromagnetic waves radiated from devices external to the electronic information device 100, and obtains communication data; A wired communication unit 112 that communicates communication data with an external device by wire, a storage unit 113 that stores various data, and a main body control unit 114 that controls the overall operation of the electronic information device 100 are provided.

  The position calculation unit 30, the drive start signal generation unit 40, and the drive timing determination unit 60 described above are included in the main body control unit 114, for example. The storage unit 50 is included in the storage unit 113, for example.

  Note that the above-described transmission / reception control unit 25 may be a part of the main body control unit 114 instead of the touch panel controller 104. Moreover, the electronic information device 100 shown in FIG. 10 is only one of application examples of the display device X and the touch panel systems 1 and 1A. The display device X and the touch panel system 1, 1 </ b> A described above can be applied to an electronic information device having a configuration different from that of the electronic information device 100.

<< Deformation, etc. >>
In FIG. 4, the case where the sample hold unit 222 obtains the response signal Sa only once after the horizontal synchronization signal H rises from low to high and then rises from low to high is illustrated. The unit 222 may acquire the response signal Sa twice or more. Also in this case, the sample-and-hold unit 222 performs the response signal twice or more in a period in which the level of the noise N is relatively low between the horizontal synchronization signal H rising from low to high and the next rising from low to high. What is necessary is just to acquire Sa.

  Further, in FIG. 4, the case where the signal level of the drive start signal Cst rises from low to high once every time the horizontal synchronization signal H rises from low to high is illustrated, but the drive start signal Cst rises from low to high. You may reduce the number of times you stand up. For example, every time the horizontal synchronization signal H rises from low to high twice, the drive start signal Cst may rise from low to high once. Further, in this case, after the drive start signal Cst rises from low to high, the drive period Td may be continued twice after the drive start waiting period Ts has elapsed.

  However, as shown in FIG. 4, every time the horizontal synchronization signal H rises from low to high once, if the drive start signal Cst rises from low to high once, the sample hold unit 222 acquires the response signal Sa. This is preferable because the timing to perform can be controlled with high accuracy. In particular, as described above, in the case where the sample hold unit 222 acquires the response signal Sa twice or more after the horizontal synchronizing signal H rises from low to high and then rises from low to high, It is preferable that the driving start signal Cst rises from low to high once every time the horizontal synchronization signal H rises from low to high.

  Further, the touch panel controller 20 may drive the touch panel 10 at a timing based on a signal for operating the display device X other than the horizontal synchronization signal H to acquire the response signal Ss.

  In addition, as an embodiment of the present invention, the touch panel system 1, 1A that includes the capacitive touch panel 10 that is a projection type and is applied to the display device X that is a liquid crystal display has been illustrated. The touch panel system may be a touch panel system including another type of touch panel, or may be a touch panel system applied to a display device other than a liquid crystal display.

  The touch panel system according to the present invention can be suitably used in a touch panel system including a touch panel provided on a display surface of a display device, an electronic information device including the touch panel system, and a manufacturing method of the touch panel system.

DESCRIPTION OF SYMBOLS 1,1A: Touch panel system 10: Touch panel 20: Touch panel controller 21: Transmission part 211: Drive signal generation part 22: Reception part 221: Amplifier part 222: Sample hold part 223: AD conversion part 224: Decoding part 23: Transmission side interface 24: reception side interface 25: transmission / reception control unit 30: position calculation unit 40: drive start signal generation unit 41: decoder 42: shift register 50: storage unit 51: first register 52: second register 100: electronic information device X: Display device X1: Display surface Y: Display device drive unit H: Horizontal synchronization signal (reference signal)
P: drive start timing parameter U: driving timing parameter DL: drive line SL: sense line Sd: drive signal Ss, Sa, Ssh, Sds: response signal Sc: output signal Cst: drive start signal Csh: sample hold timing control signal Td: Driving period T1: Reset period T2: Indicator detection period T3: Sample hold waiting period Ts: Driving start waiting period N: Noise

Claims (9)

A touch panel that is provided on the display surface of the display device and outputs a response signal corresponding to the presence or absence of an indicator that is in contact with or close to the surface and the position of the indicator;
A touch panel controller that drives the touch panel to obtain the response signal output from the touch panel;
A storage unit for storing a drive start timing parameter,
The display device operates in synchronization with a reference signal whose signal level changes in a predetermined cycle.
The touch panel controller drives the touch panel at a timing when a period corresponding to the drive start timing parameter has elapsed after a signal level of the reference signal has changed a predetermined amount.   The timing at which the touch panel controller acquires the response signal is from when the signal level of the reference signal changes to a predetermined change until the next change, and the level of noise generated by the display device is relative The touch panel system according to claim 1, wherein the drive start timing parameter is determined so as to correspond to an extremely small period. The touch panel controller is
A drive unit that gives a drive signal to the touch panel and drives the touch panel to output the response signal;
A receiver for acquiring the response signal;
A transmission / reception control unit for controlling operations of the transmission unit and the reception unit,
The said transmission / reception control part controls the timing which the said transmission part gives the said drive signal to the said touch panel, and the timing when the said receiving part acquires the said response signal, respectively. Touch panel system. After the signal level of the reference signal has changed to a predetermined level, the transmission / reception control unit is configured to provide the drive signal to the touch panel at a timing when a period corresponding to the drive start timing parameter has elapsed. Control the transmitter,
The signal level of the reference signal undergoes a predetermined change, and after the period corresponding to the drive start timing parameter has elapsed, the reception unit acquires the response signal at a timing when a predetermined period has elapsed. The touch panel system according to claim 3, wherein the transmission / reception control unit controls the receiving unit. A drive start signal generating unit that supplies a drive start signal generated based on the reference signal and the drive start timing parameter to the transmission / reception control unit;
The drive start signal generation unit generates the drive start signal whose signal level changes at a timing when a period corresponding to the drive start timing parameter has elapsed after the signal level of the reference signal has changed. And
The transmission / reception control unit includes:
Controlling the transmission unit to give the drive signal to the touch panel at a timing when the signal level of the drive start signal changes a predetermined amount;
5. The touch panel according to claim 4, wherein the receiving unit is controlled to acquire the response signal at a timing when the predetermined period has elapsed after a signal level of the drive start signal has changed. system. A drive timing determination unit that determines the drive start timing parameter and stores it in the storage unit;
The drive timing determination unit
The touch panel controller acquires a noise level included in each of the response signals acquired by driving the touch panel at a plurality of different timings based on a timing at which the signal level of the reference signal changes a predetermined amount. Calculate
The timing at which the touch panel controller acquires the response signal is a period from when the signal level of the reference signal changes to a predetermined change until the next change, and in a period when the noise level is relatively small. The touch panel system according to claim 1, wherein the drive start timing parameter is determined and stored in the storage unit so as to be applicable.   The touch panel system according to claim 1, wherein the reference signal is a horizontal synchronization signal. The touch panel system according to any one of claims 1 to 7,
The display device;
An electronic information device characterized by comprising: It is a manufacturing method of a touch panel system given in any 1 paragraph of Claims 1-7,
A noise measuring step for measuring a level of noise generated by the display device;
The timing at which the touch panel controller acquires the response signal is a period from when the signal level of the reference signal changes to a predetermined change until the next change, and in a period when the noise level is relatively small. As applicable, the drive start timing parameter determination step for determining the drive start timing parameter and storing it in the storage unit;
A method for manufacturing a touch panel system, comprising:

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