CN212322228U - Touch panel - Google Patents

Abstract

A touch panel is characterized by comprising: the touch sensor device comprises a touch sensor (20) of a1 st detection mode, a pressure-sensitive sensor (30) of a2 nd detection mode different from the 1 st detection mode, detection circuits (55A, 55B) connected to the touch sensor (20), and a processing unit (58) connected to the detection circuits (55A, 55B).

Description

Touch panel

Technical Field

The utility model relates to a touch panel of touch operation of detection user.

Background

Patent document 1 discloses a sensor device that detects a touch operation and a press operation on an operation surface. The sensor device of patent document 1 includes a capacitive touch panel and a pressure-sensitive sensor. The sensor device of patent document 1 includes a2 nd switching circuit. The sensor device of patent document 1 switches the 2 nd switching circuit, thereby allowing the detection circuit for the touch panel to be used as a detection circuit for the pressure sensitive sensor.

Patent document 1: japanese patent laid-open publication No. 2011-134000

The pressure-sensitive sensor disclosed in patent document 1 is a capacitive sensor. Patent document 1 does not describe any use of a pressure-sensitive sensor other than the capacitive type.

SUMMERY OF THE UTILITY MODEL

An object of the present invention is to provide a touch panel using a pressure-sensitive sensor other than a touch sensor and a capacitive sensor.

The utility model discloses a touch panel's characterized in that possesses: the touch panel includes a touch sensor of a1 st detection system, a pressure-sensitive sensor of a2 nd detection system different from the 1 st detection system, a detection circuit connected to the touch sensor and the pressure-sensitive sensor, and a processing unit connected to the detection circuit.

As described above, the touch panel of the present invention connects the pressure-sensitive sensor of the 2 nd detection system, which is different from the touch sensor of the 1 st detection system, to the processing unit (processing unit for touch sensor) shared by the touch sensors. Therefore, the touch panel of the present invention can use the detection circuit for the touch sensor as the detection circuit for the pressure-sensitive sensor.

According to the utility model discloses, can be with the detection circuitry that touch sensor used for detection circuitry that pressure sensitive sensor used.

Drawings

Fig. 1 is an external perspective view of a display device 1 provided with a touch panel.

Fig. 2 is a side sectional view of the display device 1.

Fig. 3 (a) is a plan view showing an example of the electrode arrangement of the touch sensor 20, and fig. 3 (B) is a plan view showing an example of the electrode arrangement of the pressure-sensitive sensor 30.

Fig. 4 is a block diagram showing a configuration of the touch panel 10 including the touch sensor 20 and the pressure-sensitive sensor 30.

Fig. 5 is a circuit diagram showing a configuration example of the charge-voltage conversion circuit 91.

Fig. 6 is a circuit diagram showing a modification of the charge-voltage conversion circuit 91.

Fig. 7 (a) is a block diagram showing the configuration of the touch panel 10B of modification 1, and fig. 7 (B) is a circuit diagram showing a partial configuration of the detection circuit 55B.

Fig. 8 is a block diagram showing a configuration of a touch panel 10C according to modification 2.

Fig. 9 is a circuit diagram showing a modification of the voltage-current conversion circuit 92.

Fig. 10 is a circuit diagram showing a partial structure of a touch panel in the case of using the resistive pressure-sensitive sensor 30F.

Fig. 11 is a block diagram showing a configuration of a touch panel 10D according to modification 3.

Fig. 12 (a) is a cross-sectional view of the display device 1A including the touch panel 10D, and fig. 12 (B) is a plan view of the flexible substrate 300.

Fig. 13 is a block diagram showing the configuration of a touch panel 10E according to modification 4.

Fig. 14 is a block diagram showing a configuration of a touch panel 10F according to modification 5.

Fig. 15 is a plan view showing another example of the electrode arrangement of the pressure-sensitive sensor.

Fig. 16 is a block diagram showing the structure of the touch panel 10G provided with the pressure-sensitive sensor 30C.

Detailed Description

Hereinafter, a display device 1 including a touch panel according to the present invention will be described with reference to the drawings. Fig. 1 is an external perspective view of the display device 1. In the present embodiment, the width direction (lateral direction) of the housing 50 is defined as the X direction, the length direction (longitudinal direction) is defined as the Y direction, and the thickness direction is defined as the Z direction.

As shown in the external perspective view of fig. 1, the display device 1 includes a cubic housing 50 and a planar front panel 40 disposed in an opening portion on an upper surface of the housing 50 in terms of external appearance. The display device 1 is an information processing device such as a smartphone or a tablet terminal. The surface panel 40 functions as an operation surface on which a user performs a touch operation using a finger, a pen, or the like.

Fig. 2 is a side sectional view of the display device 1. As shown in fig. 2, the surface panel 40, the touch sensor 20, and the pressure-sensitive sensor 30 are arranged in this order from the opening (the surface panel 40) side of the housing 50 along the Z-axis direction inside the housing 50.

The touch sensor 20, the pressure-sensitive sensor 30, and the surface panel 40 have a flat plate shape. The main surfaces of the touch sensor 20, the pressure-sensitive sensor 30, and the surface panel 40 are disposed inside the case 50 and face the main surface of the surface panel 40. The main surfaces of the touch sensor 20 and the pressure-sensitive sensor 30 are connected to each other by an adhesive 70.

A circuit board 80 is disposed on the housing 50. The circuit board 80 is connected to the touch sensor 20, the pressure-sensitive sensor 30, or the surface panel 40 via a flexible cable, not shown. The circuit board 80 may be integrated with the flexible cable using a flexible board material such as a flexible board, or may be formed as a part of a main board.

The touch sensor 20 is a capacitive sensor. The touch sensor 20 includes a1 st electrode 21, an insulating substrate 22, and a2 nd electrode 23. The insulating substrate 22 is made of a transparent material, for example, PMMA (acrylic resin). The 1 st electrode 21 is disposed on the front surface side of the insulating substrate 22, and the 2 nd electrode 23 is disposed on the rear surface side.

The 1 st electrode 21 and the 2 nd electrode 23 are all made of a material having transparency, for example, a material containing Indium Tin Oxide (ITO), zinc oxide (ZnO), silver nanowires, or polythiophene as a main component.

Fig. 3 (a) is a plan view showing an example of an electrode arrangement manner of the touch sensor 20. The 1 st electrode 21 is arranged in a rectangular shape elongated in one direction in a plan view, and the longitudinal direction is parallel to the Y direction. The 1 st electrodes 21 are arranged at predetermined intervals along the X direction.

The 2 nd electrode 23 also has a rectangular shape elongated in one direction in a plan view. The 2 nd electrode 23 is disposed such that the longitudinal direction is parallel to the X direction. The plurality of 2 nd electrodes 23 are arranged at predetermined intervals along the Y direction.

Fig. 4 is a block diagram showing a configuration of the touch panel 10 including the touch sensor 20 and the pressure-sensitive sensor 30. The touch panel 10 includes a touch sensor 20, a pressure-sensitive sensor 30, and a signal processing circuit 51. In this example, the touch panel 10 includes a reference voltage source 90, a charge-voltage conversion circuit 91, and a voltage-current conversion circuit 92. The signal processing circuit 51, the reference voltage source 90, the charge-voltage conversion circuit 91, and the voltage-current conversion circuit 92 are mounted on the circuit board 80.

The touch sensor 20 is connected to the signal processing circuit 51. The signal processing circuit 51 includes a plurality of detection circuits 55A, 55B, a signal generation circuit 57, and a processing unit 58. The detection circuit 55A is an example of the "1 st detection circuit" of the present invention, and the detection circuit 55B is an example of the "2 nd detection circuit" of the present invention. In addition, the detection circuit 55A and the detection circuit 55B are integrated into one component, which is an example of the "detection circuit" of the present invention.

The signal generation circuit 57 applies a pulse-like voltage signal to the 1 st electrode 21 or the 2 nd electrode 23 of the touch sensor 20. The plurality of detection circuits 55A are connected to the 1 st electrode 21 or the 2 nd electrode 23 of the touch sensor 20, respectively. The plurality of detection circuits 55A detect the amount of charge (current signal) flowing from the 1 st electrode or the 2 nd electrode 23 into the detection circuit 55A based on the voltage signal applied by the signal generation circuit 57.

When the user touches the surface panel 40 with a finger, a pen, or the like, part of the electric charges generated in the 1 st electrode 21 and the 2 nd electrode 23 flows into the finger or the pen of the user. Therefore, the amount of charge (current value) flowing into the detection circuit 55A decreases. The processing unit 58 detects the presence or absence of a touch operation and a touch position based on a change in the current value detected by the detection circuit 55A.

Returning to fig. 2, the pressure-sensitive sensor 30 includes the 1 st electrode 31, the piezoelectric film 32, and the 2 nd electrode 33 in this order from the front panel 40 side. As shown in the plan view of fig. 3 (B), the 1 st electrode 31 and the 2 nd electrode 33 are arranged so as to cover substantially the entire principal surface of the piezoelectric film 32. In fig. 3 (B), the 1 st electrode 31 is omitted, but the main surface of the 1 st electrode 31 has the same area as the main surface of the 2 nd electrode 33.

The 1 st electrode 31 and the 2 nd electrode 33 are made of a material having transparency, for example, a material containing Indium Tin Oxide (ITO), zinc oxide (ZnO), silver nanowires, or polythiophene as a main component.

The piezoelectric film 32 is deflected in the normal direction by the user pressing the surface panel 40, and generates electric charges. The piezoelectric film 32 is made of a transparent material, for example, a chiral polymer. More preferably, the piezoelectric film 32 is a uniaxially stretched polylactic acid (PLA), and further an L-shaped polylactic acid (PLLA).

The chiral polymer has a helical structure in its main chain, and has piezoelectricity when the molecule is oriented by uniaxial stretching. The charge amount of the uniaxially stretched chiral polymer is uniquely determined by the shear strain applied along the molecular axis of the helical molecule.

The piezoelectric constant of uniaxially stretched PLLA is a very high type among polymers. That is, the pressing operation can be detected with high sensitivity, and the electric charge corresponding to the pressing amount can be output with high accuracy.

Further, since the chiral polymer generates piezoelectricity in the orientation treatment of molecules formed by stretching or the like, it is not necessary to perform polling treatment. In particular, polylactic acid does not have pyroelectricity, and therefore, even when heat is transmitted from a user's finger or the like, the amount of generated electric charge does not change. Further, there is no case where the pressing sensitivity is affected by heat generation of the device, a change in ambient temperature, or the like. In particular, polylactic acid is effective for small electronic devices such as smartphones and tablet terminals in which a battery that easily generates heat is disposed close to a piezoelectric film. The piezoelectric constant of polylactic acid does not change with time, and is extremely stable.

When the surface panel 40 is pressed by a user, the piezoelectric film 32 is elongated or contracted in the horizontal direction. Preferably, the molecular axis is arranged such that the expansion and contraction caused by the pressing operation is shear strain with respect to the molecular axis of the helical molecule. In the uniaxially stretched polylactic acid film, helical molecules contributing to piezoelectricity are oriented in the direction of the stretching axis. In the present embodiment, the piezoelectric film 32 is disposed such that the uniaxial stretching direction forms an angle of substantially 45 ° with respect to the X direction and the Y direction. Such a configuration is made, whereby the pressing operation can be detected with higher sensitivity. Further, the uniaxial stretching direction of 45 ° is most effective, but even in the range of 45 ± 10 °, for example, substantially the same effect can be obtained.

The stretch ratio is preferably about 3 to 8 times. By performing heat treatment after stretching, crystallization of the drawn chain crystal of polylactic acid is promoted, and the piezoelectric constant is improved. In the case of biaxial stretching, the same effect as that of uniaxial stretching can be obtained by making the stretching ratio of each axis different. For example, when 8-fold stretching is performed in the X-axis direction with a certain direction being the X-axis and 2-fold stretching is performed in the Y-axis direction orthogonal to the X-axis, the piezoelectric constant can be obtained with substantially the same effect as that of the case where uniaxial stretching is performed approximately 4-fold in the X-axis direction. Since a film that has been subjected to simple uniaxial stretching is likely to be split in the stretching axis direction, the above biaxial stretching can increase the strength a little.

As shown in fig. 4, a reference voltage source 90 and a charge-voltage conversion circuit 91 are connected to the pressure-sensitive sensor 30. The reference voltage source 90 applies a reference voltage to the 1 st electrode 31 or the 2 nd electrode 33 of the pressure sensitive sensor 30.

If the user presses the surface panel 40, the piezoelectric film 32 generates electric charges. The charge-voltage conversion circuit 91 is connected to the 1 st electrode 31 or the 2 nd electrode 33, and converts the charge generated in the piezoelectric film 32 into a voltage.

Fig. 5 is a circuit diagram showing a configuration example of the charge-voltage conversion circuit 91. The charge-voltage conversion circuit 91 includes an operational amplifier a, a resistor R, and a capacitor C. The inverting input terminal of the operational amplifier a is connected to the 1 st electrode 31 or the 2 nd electrode 33. The non-inverting input terminal of the operational amplifier a is connected to a reference voltage source 90. The output terminal of the operational amplifier a is feedback-connected to the inverting input terminal of the operational amplifier a via a parallel circuit of a resistor R and a capacitor C. With such a configuration, the charge-voltage conversion circuit 91 constitutes an integration circuit, and converts the charge generated in the piezoelectric film 32 into a voltage.

The voltage-to-current conversion circuit 92 converts the voltage signal output from the charge-to-voltage conversion circuit 91 into a current signal. The charge-voltage conversion circuit 91 is formed of, for example, a resistor. Therefore, a current signal corresponding to the electric charge generated in the piezoelectric film 32 is input to the detection circuit 55B in the signal processing circuit 51.

The plurality of detection circuits 55A and 55B are both detection circuits for capacitive touch sensors. In other words, the detection circuits 55A and 55B are both of the same type of circuit (in the present embodiment, a circuit for current detection), and are both connected to the common processing unit 58.

The processing unit 58 detects the presence or absence of a touch operation and a touch position from the current value detected by the detection circuit 55A. The processing unit 58 detects the presence or absence of the pressing operation and the amount of pressing based on the current value detected by the detection circuit 55B.

As described above, the capacitive touch sensor inputs a voltage signal for detection. Since the capacitive touch sensor continues to generate electric charges by a voltage signal for detection, a current signal is input to the detection circuit. The detection circuit for the capacitive touch sensor is adjusted to a sensitivity for detecting the current signal. On the other hand, when the user presses, the pressure-sensitive sensor intermittently generates electric charges. Therefore, the amount of charge (current value) flowing into the detection circuit is greatly different between the capacitive touch sensor and the pressure-sensitive sensor. However, the pressure-sensitive sensor 30 of the present embodiment is connected 2 to the detection circuit 55B via the charge-voltage conversion circuit 91 and the voltage-current conversion circuit 9. Accordingly, the electric charges intermittently generated in the pressure sensitive sensor 30 continue to be converted into a current signal that can be detected. Thus, the touch panel of the present embodiment can use the detection circuit for the capacitive touch sensor (the detection circuit 55A as the 1 st detection circuit and the detection circuit 55B as the 2 nd detection circuit) as the detection circuit for the pressure sensitive sensor.

Next, fig. 6 is a circuit diagram showing a modification of the charge-voltage conversion circuit 91. The charge-voltage conversion circuit 91 of the modification of fig. 6 includes an operational amplifier a, resistors R1, R2, R3, and a capacitor C. The inverting input terminal of the operational amplifier a is connected to the 1 st electrode 31 or the 2 nd electrode 33. The non-inverting input terminal of the operational amplifier a is connected to the input terminal of the charge-voltage conversion circuit 91 and the reference voltage source 90. The non-inverting input terminal is connected to the reference voltage source 90 via a parallel circuit of a resistor R1 and a capacitor C. The inverting input terminal of the operational amplifier a is connected to the reference voltage source 90 via a resistor R2. The output terminal of the operational amplifier a is feedback-connected to the inverting input terminal of the operational amplifier a via a resistor R3.

With such a configuration, the charge-voltage conversion circuit 91 also constitutes an integration circuit, and converts the charge generated in the piezoelectric film 32 into a voltage. The charge-voltage conversion circuit 91 shown in fig. 6 has a gain corresponding to the ratio of the feedback resistor R3 and the resistor R2, and thus constitutes an amplifier circuit. Therefore, the charge-voltage conversion circuit 91 shown in fig. 6 can improve the sensitivity of the pressure-sensitive sensor 30.

Modification 1 of touch panel

Next, fig. 7 (a) is a block diagram showing a configuration of a touch panel 10B of modification 1. Fig. 7 (B) is a circuit diagram showing a partial configuration of the detection circuit 55B. Since the detection circuit 55A and the detection circuit 55B have the same configuration as described above, fig. 7 (B) representatively shows the configuration of the detection circuit 55B.

The touch panel 10B is different from the touch panel 10 shown in fig. 4 in that the voltage-current conversion circuit 92 is omitted. As shown in fig. 7B, the detection circuit 55B includes at least a sample-and-hold circuit 550, an ADC (AD converter) 551, and an initialization circuit 552.

The other structure of the touch panel 10B is the same as the touch panel 10 shown in fig. 4. The same reference numerals are given to the common structure with the touch panel 10 of fig. 4, and the description thereof is omitted.

At each measurement timing of the touch sensor 20, the detection circuit 55B connects the initialization circuit 552 to the capacitor of the sample-and-hold circuit 550 to initialize the capacitor of the sample-and-hold circuit 550. Thereafter, the connection between the sample-and-hold circuit 550 and the initialization circuit 552 is released, and the sample-and-hold circuit 550 is connected to the charge-voltage conversion circuit 91. The sample-and-hold circuit 550 is connected to the ADC 551. The voltage signal output from the charge-voltage conversion circuit 91 is held by the sample-and-hold circuit 550. The ADC551 performs digital conversion on the held voltage signal.

When the capacitance C of the capacitor in the sample-and-hold circuit 550, the voltage value (voltage value at the start of measurement) V of the charge-voltage conversion circuit 91, and the number of measurements n per unit time are set, the current value I flowing through the detection circuit 55B is represented by I ═ n · C · V. That is, the current value I flowing through the detection circuit 55B is proportional to the output value of the pressure-sensitive sensor 30.

Therefore, even when the voltage-current conversion circuit 92 is omitted, the pressure-sensitive sensor 30 can be connected to the detection circuit 55B, which is a circuit for current detection.

Modification 2 of touch panel

Next, fig. 8 is a block diagram showing a configuration of a touch panel 10C of modification 2. The same reference numerals are given to the components common to fig. 4, and the description thereof is omitted.

The voltage-current conversion circuit 92 and the detection circuit 55C are connected to the ground via a capacitor. The detection circuit 55C is connected to the signal generation circuit 57. The detection circuit 55C is a detection circuit of a self-capacitance type touch sensor. The detection circuit 55C is an example of the "2 nd detection circuit" of the present invention. In some cases, an information processing apparatus such as a smartphone includes a mutual capacitance type detection circuit and a self-capacitance type detection circuit, as in the example of fig. 8. According to the configuration of modification 2, the pressure-sensitive sensor 30 can be connected to the self-capacitance detection circuit 55C instead of the mutual capacitance detection circuit 55A and the detection circuit 55B.

Next, fig. 9 is a circuit diagram showing a modification of the voltage-current conversion circuit 92. The voltage-current conversion circuit 92 of this modification includes operational amplifiers a1 and a2, resistors R1, R2, R3, R4, and R5. The inverting input terminal of the operational amplifier a1 is connected to the reference voltage source 90 via a resistor R1. The non-inverting input terminal of the operational amplifier a1 is connected to the 1 st electrode 31 or the 2 nd electrode 33 via a resistor R3. The output terminal of the operational amplifier a1 is feedback-connected to the inverting input terminal of the operational amplifier a1 via a resistor R2. The output terminal of the operational amplifier a1 is connected to the non-inverting input terminal of the operational amplifier a2 and the output terminal via a resistor R5. The output terminal of the operational amplifier a2 is feedback-connected to the inverting input terminal. The output terminal of the operational amplifier a2 is feedback-connected to the non-inverting input terminal of the operational amplifier a1 via a resistor R4.

The operational amplifier a1 is a non-inverting amplifier circuit whose gain is determined by the ratio of the resistor R1 and the resistor R2. The operational amplifier a2 constitutes a voltage follower.

When the load resistance in the subsequent stage is low, the operational amplifier a2 may be omitted.

With such a configuration, the voltage-current conversion circuit 92 outputs a current value corresponding to the input voltage value. The output current value is determined by the ratio of the resistors R3, R4, and R5. With this configuration, the linearity of the current signal with respect to the voltage signal is improved as compared with the voltage-to-current conversion circuit 92 configured only with a resistor.

Next, fig. 10 is a circuit diagram showing a partial structure of the touch panel in the case of using the resistive pressure-sensitive sensor 30F. The pressure-sensitive sensor 30F shown in fig. 10 is constituted by a bridge circuit constituted by a plurality of resistors. The output of the pressure-sensitive sensor 30F is connected to the amplification circuit 95. When the user presses the surface panel 40, the pressure-sensitive sensor 30F is deformed, and the values of the resistors constituting the bridge circuit are changed. Therefore, a potential difference is generated between both input terminals of the operational amplifier constituting the amplifier circuit 95, and a voltage signal is output to the voltage-to-current conversion circuit 92. Thus, the pressure-sensitive sensor of the present invention is not limited to the piezoelectric type, but can be the resistance type.

Modification 3 of touch panel

Next, fig. 11 is a block diagram showing a configuration of a touch panel 10D of modification 3. The same reference numerals are given to the components common to fig. 4, and the description thereof is omitted. Fig. 12 (a) is a cross-sectional view of the display device 1A including the touch panel 10D.

The display device 1A includes the 2 nd pressure-sensitive sensor 30B and the flexible substrate 300. The 2 nd pressure-sensitive sensor 30B is smaller than the pressure-sensitive sensor 30. The 2 nd pressure-sensitive sensor 30B is disposed on the inner wall of the side surface of the housing 50. For example, instead of a physical switch such as a power button or a volume button, the 2 nd pressure-sensitive sensor 30B is provided in order to detect a pressing operation of the side by the user.

The 2 nd pressure-sensitive sensor 30B is connected to the reference voltage source 90 and the charge-voltage conversion circuit 91 of the circuit board 80 via the flexible substrate 300. Fig. 12 (B) is a plan view of the flexible substrate 300. The flexible substrate 300 is made of, for example, a resin base material and has flexibility. The flexible substrate 300 is formed in a zigzag shape. The conductor pattern 301 is formed along the shape of the flexible substrate 300 on the main surface or inside the flexible substrate 300.

The circuit board 80 is disposed at a position close to the capacitive sensor. However, as in the example of fig. 12 (a), the circuit board 80 may be disposed at a position away from the capacitive sensor. The present invention is characterized in that the pressure sensitive sensor is connected to the detection circuit of the capacitive sensor, and therefore, the wiring needs to be routed to the circuit of the capacitive sensor from the pressure sensitive sensor disposed at a position away from the circuit board 80. In such a case, the circuit board 80 is often disposed on the display module side, and the pressure-sensitive sensor is often disposed on the main body side. At the final part of the assembly process, the display module is bonded to the main body from the upper part. The pressure sensitive sensor and the circuit substrate must be attached before bonding. In this case, if the flexible substrate does not have a certain length, the workability of connection is deteriorated. Therefore, there is a problem that the flexible board or the connector for connection may be damaged at the time of connection due to an increase in assembly cost caused by an increase in operation time.

The flexible substrate 300 is formed in a zigzag shape. Therefore, the flexible substrate 300 can be elongated to some extent without being damaged. Thus, even when the 2 nd pressure-sensitive sensor 30B is provided at a position separated from the circuit board 80, the flexible substrate 300 can be easily mounted at the time of manufacture, and the above-described problem can be solved.

Modification example 4 of touch panel

Fig. 13 is a block diagram showing the configuration of a touch panel 10E according to modification 4. The same reference numerals are given to the components common to fig. 4, and the description thereof is omitted.

The touch panel 10E incorporates a reference voltage source 90 in the signal processing circuit 51. That is, the reference voltage source 90 is a reference voltage source for the touch sensor. In the touch panel 10E of modification 4, the reference voltage source for the touch sensor is also used as the reference voltage source for the pressure-sensitive sensor. Thus, it is not necessary to separately prepare a reference voltage source for the pressure-sensitive sensor, and the cost can be reduced. Further, all the reference potentials in the touch panel 10E are common, and no difference is generated in the reference potentials, so that the usable voltage range can be expanded. Further, by incorporating the reference voltage source 90 in the signal processing circuit 51, it is possible to use a reference voltage that is less susceptible to the influence of variations in the power supply voltage, which is referred to as a bandgap reference voltage source, for example. Therefore, the suppression performance of the power supply voltage variation of the pressure-sensitive sensor 30 is more excellent.

Modification example 5 of touch panel

Next, fig. 14 is a block diagram showing a configuration of a touch panel 10F of modification 5. The same reference numerals are given to the components common to fig. 4, and the description thereof is omitted.

The touch panel 10F includes a switch circuit 920. The switch circuit 920 is connected to the detection circuit 55A, the touch sensor 20, and the voltage-current conversion circuit 92.

The touch panel 10F of modification 5 switches the switch circuit 920, and connects the touch sensor 20 or the voltage-to-current conversion circuit 92 to the detection circuit 55A. Thus, the detection circuit 55A of the touch sensor 20 is also used as a detection circuit for the pressure-sensitive sensor 30.

Fig. 15 is a plan view showing another example of the electrode arrangement of the pressure-sensitive sensor. The pressure-sensitive sensor 30C of fig. 15 divides the electrode for charge detection into the 2 nd electrode 33A and the 2 nd electrode 33B. The 1 st electrode 31, not shown, is disposed so as to cover substantially the entire principal surface of the piezoelectric film 32. The 2 nd electrode 33A and the 2 nd electrode 33B are connected to different circuits, respectively.

Fig. 16 is a block diagram showing the structure of the touch panel 10G provided with the pressure-sensitive sensor 30C. The same reference numerals are given to the components common to fig. 4, and the description thereof is omitted.

The pressure-sensitive sensor 30C is connected to 2 charge-voltage conversion circuits 91, respectively. The 2 nd electrode 33A and the 2 nd electrode 33B are connected to different charge-voltage conversion circuits 91, respectively. Thereby, the generated electric charges (current values) are processed for the 2 nd electrode 33A and the 2 nd electrode 33B, respectively. In other words, the processing unit 58 can detect the pressed position by determining whether or not the pressing operation is performed on each of the 2 nd electrode 33A and the 2 nd electrode 33B. For example, when the pressing operation is detected by the detection circuit 55B connected to the 2 nd electrode 33A, the processing unit 58 can determine that the pressing operation is performed at the left side position in the plan view.

Further, the same structure and function can be exhibited even if the electrode of one pressure sensitive sensor is divided into a plurality of pressure sensitive sensors, not by dividing the electrode of one pressure sensitive sensor.

Further, the processing section 58 can detect an operation mode of not less than the total number of detection circuits (1 st detection circuit and 2 nd detection circuit). For example, the processing unit 58 detects pressing operations in different operation modes, such as a mode in which only 1 pressing is performed within a predetermined time (click mode), a mode in which pressing continues for a predetermined time or longer (long-press mode), or a mode in which 2 pressing operations are repeated within a predetermined time (double-click mode). Alternatively, the processing unit 58 may detect a different operation mode according to the amount of pressing. In this way, the processing section 58 can detect a plurality of operation modes for one detection circuit.

Finally, it should be understood that all the points in the above description of the embodiments are illustrative and not restrictive. The scope of the present invention is defined by the claims, not by the above embodiments. In addition, the scope of the present invention includes the scope equivalent to the claims.

Description of reference numerals

A. A1, a2 … operational amplifier; a C … capacitor; r, R1, R2, R3, R4, R5 … resistance; 1 … display device; 10. 10B, 10C, 10D, 10E, 10F, 10G … touch panels; 20 … touch sensor; 21 … electrode No. 1; 22 … insulating substrate; 23, 23 …, electrode No. 2; 30. 30F … pressure sensitive sensor; 30B …, 2 nd pressure sensitive sensor; a 30C … pressure sensitive sensor; 31 … electrode No. 1; 32 … piezoelectric film; 33. 33A, 33B …, 2 nd electrode; 40 … surface panel; 50 … a housing; 51 … signal processing circuit; 55A, 55B, 55C … detection circuit; a 57 … signal generating circuit; 58 … processing part; 70 … adhesive; 80 … circuit substrate; 90 … reference voltage source; 91 … charge-to-voltage conversion circuit; 92 … voltage-to-current conversion circuit; 95 … amplifying circuit; 300 … flexible substrate; 301 … conductor pattern; 550 … sample-and-hold circuit; 551 … ADC; 552 … initializing the circuit; 920 … switching circuits.

Claims (11)

1. A touch panel is characterized by comprising:

touch sensor of the 1 st detection mode,

A pressure-sensitive sensor of the 2 nd detection mode different from the 1 st detection mode,

A detection circuit connected to the touch sensor and the pressure-sensitive sensor, and

a processing unit connected to the detection circuit,

the detection circuit has a1 st detection circuit and a2 nd detection circuit,

the touch sensor is connected with the 1 st detection circuit,

the pressure-sensitive sensor is connected with the No. 2 detection circuit,

the touch panel further includes a charge-to-voltage conversion circuit and a voltage-to-current conversion circuit,

the 2 nd detection circuit is connected to the pressure-sensitive sensor via the charge-voltage conversion circuit and the voltage-current conversion circuit.

2. The touch panel according to claim 1,

the pressure sensitive sensor is either piezoelectric or resistive.

3. The touch panel according to claim 1 or 2,

the processing unit processes the signal of the 1 st detection method.

4. The touch panel according to claim 1 or 2,

the 1 st detection circuit and the 2 nd detection circuit are circuits for current detection.

5. The touch panel according to claim 1 or 2,

the 2 nd detection circuit comprises a plurality of 2 nd detection circuits,

the pressure-sensitive sensor includes a plurality of electrodes on any one main surface,

the plurality of electrodes are connected to different 2 nd detection circuits, respectively.

6. The touch panel according to claim 1 or 2,

the 2 nd detection circuit comprises a plurality of 2 nd detection circuits,

the pressure sensitive sensor comprises a plurality of pressure sensitive sensors,

the plurality of pressure-sensitive sensors are respectively connected with different No. 2 detection circuits.

7. The touch panel according to claim 5,

each of the 2 nd detection circuits is a current detection circuit.

8. The touch panel according to claim 1 or 2,

the processing section detects an operation mode of the 1 st detection circuit and the 2 nd detection circuit or more in total.

9. The touch panel according to claim 1 or 2,

the voltage-current conversion circuit comprises an amplifying circuit.

10. The touch panel according to claim 1 or 2,

comprises a flexible substrate having flexibility and being in a zigzag shape,

the 2 nd detection circuit is connected to the pressure-sensitive sensor via the meandering conductor of the flexible substrate.

11. The touch panel according to claim 1 or 2,

the processing unit processes the detection results of the 1 st detection circuit and the 2 nd detection circuit.

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