JP2008070983A - Input device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an input device for giving a tactile to guide a touch input position when a user performs a touch input operation to a prescribed touch position to a user who performs the touch operation. <P>SOLUTION: An input device for inputting input information is provided with an operation face, a contact position detection part, a control part and a force generation part. The contact position detection part detects the contact position of an object brought into contact with the operation face as input information. A control part sets a guide target to guide the contact position to an operation face. A force generation part gives force following the operation face to a direction going from the contact position toward a guide target to the object brought into contact with the operation face. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an input device, and more particularly to an input device that performs input in accordance with an indicated position that is instructed by a user touching an operation surface.

2. Description of the Related Art Conventionally, there are input devices that perform an input operation by touching a position designated by a user, such as a touch panel or a touch pad. In addition, an input device in which a piezoelectric actuator is installed in the vicinity of an operation surface that a user contacts is also disclosed (for example, see Patent Document 1). The input device disclosed in Patent Document 1 performs input by detecting a contact position of a user with a capacitive sensor or the like. When contact is detected and input of a signal is received, a drive signal is supplied to the piezoelectric actuator to vibrate the contact portion and transmit the vibration to the user. As a result, the user can feel that the input has been accepted.
JP 2005-339298 A

  When the user cannot visually recognize the operation surface of the input device, the user may touch an unintended position without finding the position that the user wants to touch on the operation surface. For example, even if the input device disclosed in Patent Document 1 is used, the input device only vibrates the operation surface and transmits the vibration to the user, and the user senses that the input has been accepted. Is only possible. That is, in the input device, finding the position to be touched from the operation surface is left to the user's own operation, and the direction or the like to move the position touched by the user cannot be known from the tactile sense. Therefore, the input device cannot improve user operability.

  SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an input device that, when a user performs a touch input operation, provides a user who is performing a touch operation with a tactile sensation that guides the touch input position to a predetermined touch position.

In order to achieve the above object, the present invention has the following features.
The first invention is an input device for inputting input information. The input device includes an operation surface, a contact position detection unit, a control unit, and a force generation unit. The contact position detection unit detects a contact position of an object that is in contact with the operation surface as input information. The control unit sets a guidance target for guiding the contact position on the operation surface. The force generation unit applies a force along the operation surface to an object in contact with the operation surface in a direction from the contact position toward the guidance target.

  In a second aspect based on the first aspect, the control unit sets the guidance target at a position on the operation surface corresponding to the display position of the display button displayed on the display screen.

  In a third aspect based on the second aspect, the control unit selects a display button closest to the indicated position on the display screen corresponding to the contact position from the plurality of display buttons displayed on the display screen. The guidance target is set at a position on the operation surface corresponding to the display position of the display button.

In a fourth aspect based on the first aspect, the operation surface is formed on the surface of the elastic plate member. The force generation unit applies a force along the operation surface to the object in the direction from the contact position toward the guidance target by exciting the elastic plate member in the direction from the guidance target toward the contact position.

  In a fifth aspect based on the fourth aspect, the force generation unit includes a piezoelectric element and a voltage supply unit. The piezoelectric element is attached to the entire back surface of the elastic plate-like member and is polarized in a lattice shape. The voltage supply unit supplies a high-frequency voltage alternating between positive and negative to each electrode of the polarized piezoelectric element. The control unit includes a voltage supply control unit. The voltage supply control unit controls the high-frequency voltage supplied by the voltage supply unit so that a traveling wave travels in a direction from the guidance target toward the contact position.

  In a sixth aspect based on the fifth aspect, the piezoelectric element has a plurality of units each including a plurality of electrodes. The unit is divided into a first unit group and a second unit group. The first unit group generates a first standing wave in the elastic plate member by being supplied with a high-frequency voltage from a voltage supply unit. The second unit group is disposed at a position 90 ° away from the first unit group in the phase of the first standing wave, and is supplied with a high-frequency voltage from the voltage supply unit to generate the second standing wave. It is generated in the elastic plate member. The voltage supply unit supplies the first system high-frequency voltage to the first unit group, and supplies the second system high-frequency voltage having a phase different from that of the first system high-frequency voltage to the second unit group. The voltage supply control unit controls the phase of the first system high-frequency voltage and the second system high-frequency voltage supplied by the voltage supply unit in accordance with the direction in which the traveling wave travels.

  In a seventh aspect based on the sixth aspect, the unit is further divided into a third unit group and a fourth unit group. The third unit group causes the elastic plate-like member to generate a third standing wave that is generated in a direction perpendicular to the direction in which the first standing wave is generated when the high-frequency voltage is supplied from the voltage supply unit. The fourth unit group is disposed at a position 90 degrees away from the third unit group in the phase of the third standing wave, and is supplied with a high-frequency voltage from the voltage supply unit to generate the fourth standing wave. It is generated in the elastic plate member. The voltage supply unit further supplies the high frequency voltage of the first system to the third unit group, and supplies the high frequency voltage of the second system to the fourth unit group. The voltage supply control unit supplies the high frequency voltage to the set of the first unit group and the second unit group according to the direction in which the traveling wave travels, and the high frequency voltage to the set of the third unit group and the fourth unit group. The time to supply is controlled in a time-sharing manner.

  In an eighth aspect based on the first aspect, when the object moves while contacting the operation surface, the force generation unit gives a thrust to the object in the moving direction.

  In a ninth aspect based on the first aspect, when the object moves while contacting the operation surface, the force generation unit applies a reaction force to the object in the moving direction.

  A tenth invention is an input device for inputting input information. The input device includes an elastic plate member, a contact position detection unit, a piezoelectric element, and a voltage supply unit. The elastic plate member constitutes an operation surface on the surface thereof. The contact position detection unit detects a contact position of an object that is in contact with the operation surface as input information. The piezoelectric element is attached to the entire back surface of the elastic plate-like member and is polarized in a lattice shape. The voltage supply unit supplies a high-frequency voltage alternating between positive and negative to each electrode of the polarized piezoelectric element, and excites a traveling wave on the elastic plate member.

  According to the first aspect, when the user performs an operation for touching the operation surface, a force for guiding the user's finger or the like to the guidance target is generated according to the contact position. The user operability can be improved with respect to an operation such as touching.

According to the second aspect, it is possible to improve user operability with respect to an operation of selecting a display button displayed on the display screen. For example, since the user cannot visually recognize the operation surface, the touch position corresponding to the option may not be found. However, with the input device, as long as the user touches the operation surface, the user can appropriately guide the touch operation. Can do.

  According to the third aspect, the operability of the user can be improved with respect to an operation of selecting from a plurality of display buttons displayed on the display screen. For example, when a plurality of options are displayed, the input device performs a touch operation for selecting the option selected by the user as long as the user touches the operation surface corresponding to the vicinity of the position where the option selected by the user is displayed. Can be guided. Further, when the display button closest to the designated position changes while the user is touching the operation surface with a finger, a thrust for the touch operation is applied to the user's finger after a reaction force to the touch operation is applied. Therefore, in the user's operation on the operation surface, a sense of moderation corresponding to the display button is born, and the user can see that the button touched by the touch of the finger is changed. It is also useful to avoid operations such as touching the neutral region between the display buttons.

  According to the fourth aspect of the invention, a force in the direction opposite to the direction in which the traveling wave travels can be applied to the object in contact with the operation surface by exciting the traveling wave in the elastic plate member.

  According to the fifth aspect of the present invention, the electrode pitch is applied to the elastic plate member by applying a high frequency voltage to the piezoelectric element that is affixed to the entire back surface of the elastic plate member and polarized in a lattice shape. The standing wave according to the frequency can be excited, and the standing wave for generating the traveling wave can be easily excited.

  According to the sixth aspect, the traveling wave can be generated by the combined wave of the first standing wave and the second standing wave. Moreover, the direction in which the traveling wave travels can be controlled by controlling the phase of the first system high-frequency voltage and the second system high-frequency voltage.

  According to the seventh aspect of the invention, the synthesized wave of the third standing wave and the fourth standing wave is orthogonal to the traveling wave of the synthesized wave of the first standing wave and the second standing wave. A traveling wave can be generated. By generating these traveling waves in a time-sharing manner, it is possible to generate traveling waves in both the vertical and horizontal directions with respect to the operation surface, and by controlling the phase of the high-frequency voltage, the vertical and horizontal directions in which the traveling waves travel are controlled. be able to.

  According to the eighth and ninth aspects, when an operation of tracing the operation surface of the input device with a finger is performed, thrust or reaction force is applied to the user's finger in the operation direction. Therefore, in the user's operation on the operation surface, various guidance can be performed such as generating a sense of moderation of the tactile sensation, guiding the user's touch position, touching an inappropriate position by the user, and the like. Can be improved.

  According to the tenth aspect of the invention, when the user performs an operation to contact the operation surface, a force for guiding the user's finger or the like is generated according to the contact position, thereby improving the operability of the user. be able to.

  Hereinafter, an input device according to an embodiment of the present invention will be described with reference to FIG. In order to make the description more specific, the following description will be given using an example of an input device that performs input using the position touched by the user as the designated position. FIG. 1 is a block diagram showing a schematic configuration of the input device.

In FIG. 1, the input device includes a control unit 1, a track pad 2, and a traveling wave generation unit 3, and is connected to an external device 9. The external device 9 is a device to be operated by the input device.

  The control unit 1 includes a CPU (Central Processing Unit) 10, a storage unit 11, a drive circuit 12, and I / O (Input / Output) 13 and 14. A storage unit 11 and a drive circuit 12 are connected to the CPU 10. Further, the trackpad 2 is connected to the CPU 10 via the I / O 13, and the external device 9 is connected via the I / O 14.

  The storage unit 11 is configured by an internal storage medium such as a hard disk or a memory, and the CPU 10 executes various programs stored in the storage unit 11. Then, the CPU 10 outputs an operation instruction corresponding to the touch position data obtained from the track pad 2 to the external device 9 via the I / O 14. Further, the CPU 10 controls the drive circuit 12 based on the touch position data obtained from the track pad 2 and the guidance target position data obtained from the external device 9.

  The track pad 2 has an operation surface, and outputs touch position data corresponding to the position of the operation surface touched by the user to the CPU 10 via the I / O 13. The track pad 2 may be referred to as a touch pad. Here, the operation surface of the track pad 2 defines X and Y axes that are orthogonal to each other. For example, the touch position data is indicated by XY position coordinates. The traveling wave generator 3 generates traveling waves that travel in the X-axis direction and the Y-axis direction along the operation surface of the track pad 2 in accordance with a voltage (for example, AC voltage) supplied from the drive circuit 12. To do. That is, the CPU 10 can generate traveling waves that travel in the X-axis direction and the Y-axis direction along the operation surface of the track pad 2 by controlling the drive circuit 12.

  As will be apparent from the description below, the drive circuit 12 is temporally + 90 ° (+ π / 2 radians) with respect to the unit 30 that generates the A-phase standing wave and the unit 30 that generates the B-phase standing wave. Alternatively, two high-frequency voltages (for example, AC voltages) different from each other by −90 ° (−π / 2 radians) are applied. For example, the drive circuit 12 includes an oscillation circuit, a phase shift circuit, an amplifier circuit, and the like. In response to an instruction from the control unit 1, the oscillation circuit outputs an AC signal having a predetermined frequency, and an AC voltage obtained by amplifying the AC signal by the amplifier circuit is applied to the A-phase driving unit 30. At the same time, an AC signal output from the oscillation circuit is output to the phase shift circuit. In accordance with an instruction from the control unit 1, the phase of the AC signal output from the phase shift circuit is shifted by + 90 ° or −90 °, and then the AC voltage amplified by the amplifier circuit is applied to the B-phase driving unit 30. .

  The structure and operation principle of the track pad 2 and the traveling wave generator 3 will be described with reference to FIGS. FIG. 2 is a sectional view showing the internal structure of the track pad 2. FIG. 3 is a plan view showing the structure of the piezoelectric element 30 disposed on the track pad 2. FIG. 4 is a diagram illustrating an example of AC voltage connection to a plurality of cells 31. FIG. 5 is a plan view illustrating an arrangement example of the unit 30 that generates the A-phase standing wave and the unit 30 that generates the B-phase standing wave when driving in the lateral direction (X-axis direction). FIG. 6 is a diagram for explaining an example of a standing wave generated during lateral driving. FIG. 7 is a plan view showing an arrangement example of the unit 30 that generates the A-phase standing wave and the unit 30 that generates the B-phase standing wave when driven in the vertical direction (Y-axis direction).

In FIG. 2, the track pad 2 is constituted by a plate-like member made of an elastic body (rubber, resin, metal, etc.), and a plurality of protrusions 21 are formed on the entire main surface (operation surface) thereof. A touch sensor 20 is embedded along the main surface inside the elastic plate member. A piezoelectric element 30 is attached to the entire other main surface of the track pad 2. The piezoelectric element 30 corresponds to an example of the traveling wave generator 3.

  The touch sensor 20 is a device having a function of outputting coordinate data corresponding to the touch position when the one main surface (protrusion 21) is touched. The touch sensor 20 can use any system having a predetermined resolution (detection accuracy) such as a resistive film system or a capacitive coupling system. Note that the touch sensor 20 may not be embedded in the track pad 2, and for example, the touch position may be detected using an optical (infrared type) sensor.

  In FIG. 3, the piezoelectric element 30 is attached to the entire other main surface of the track pad 2. In order to drive the piezoelectric element 30, the electrode is polarized on the surface of the piezoelectric element 30 alternately in a grid pattern, that is, in a checkered pattern, and the surface vibrates. Here, each electrode polarized on the surface of the piezoelectric element 30 is referred to as a cell 31, and the positive and negative electrodes are distinguished as cells 31a and 31b.

  In this embodiment, 8 × 8 cells 31 are arranged in parallel as one group, and the group is referred to as a unit 30. That is, in the unit 30, 8 × 8 cells 31a and 31b constituting positive and negative electrodes are alternately arranged in parallel. Each unit 30 is arranged in a grid pattern on the entire other main surface of the track pad 2. Here, in order to make the arrangement positions of the units 30 specific, the units 30 arranged in the X-axis direction on the other main surface of the track pad 2 are referred to as “rows”, and the units 30 arranged in the Y-axis direction are referred to as “columns”. To do. Each unit 30 is arranged in a grid of m rows × n columns on the entire other main surface of the track pad 2.

  A predetermined gap G is formed between the units 30 disposed on the entire other main surface of the track pad 2. As for the width of the gap G, half the width of the entire cell 31 and 1.5 times the width of the entire cell 31 are alternately repeated. Specifically, the gap Gr12 between the unit 30 arranged in the first row and the unit 30 arranged in the second row is formed with a half width of the entire width of the cell 31. The gap Gr23 between the unit 30 arranged in the second row and the unit 30 arranged in the third row is formed with a width 1.5 times the entire width of the cell 31. The gap Gr34 between the unit 30 arranged in the third row and the unit 30 arranged in the fourth row is formed with a half width of the entire width of the cell 31, and the subsequent gaps G are alternately arranged with such a width. It is formed. Further, the gap Gs12 between the unit 30 arranged in the first row and the unit 30 arranged in the second row is formed with a half width of the entire width of the cell 31. The gap Gs23 between the unit 30 arranged in the second row and the unit 30 arranged in the third row is formed with a width 1.5 times the entire width of the cell 31. The gap Gs34 between the unit 30 arranged in the third row and the unit 30 arranged in the fourth row is formed with a half width of the entire width of the cell 31, and the subsequent gaps G are alternately arranged with such a width. It is formed.

  In FIG. 4, an AC voltage with a predetermined frequency output from the drive circuit 12 is applied to each unit 30. For example, one side of the AC voltage is connected to the cell 31a of each unit 30, and the other side of the AC voltage is connected to the cell 31b of each unit 30, respectively. That is, each unit 30 is supplied with an AC voltage in a checkered pattern on the grid-like electrodes (cells 31). As a result, each unit 30 expands and contracts due to its piezoelectric effect, and its surface vibrates in a wave shape.

The piezoelectric element affixed to the entire other main surface of the track pad 2 is composed of two phases: a unit 30 that generates an A-phase standing wave and a unit 30 that generates a B-phase standing wave. Yes. As shown in FIG. 5, when driving in the lateral direction (X-axis direction), the units 30 arranged in the odd rows on the entire other main surface of the track pad 2 generate A-phase standing waves, and the track pad 2 Units 30 arranged in even rows on the other main surface of the other generate a B-phase standing wave. In this case, the phase generated by the unit 30 that generates the A-phase standing wave and the phase generated by the unit 30 that generates the B-phase standing wave are shifted by 90 ° from each other. As described above, the drive circuit 12 differs from the unit 30 that generates the A-phase standing wave and the unit 30 that generates the B-phase standing wave by + 90 ° or −90 ° in time. Two systems of AC voltage are applied.

  Here, attention is focused on one row of cells 31 (shown as X1) arranged in parallel in the X-axis direction shown in FIG. When the AC voltage is applied only to the unit 30 that generates the A-phase standing wave, the standing wave A is generated in the cells 31 in the X1 row. Specifically, the positions of the peaks and valleys of the standing wave A waveform are the positions of the cells 31a and 31b of the unit 30 that generates the A-phase standing wave, and the positions of the nodes of the standing wave A waveform. Is the position of the cell 31a and the cell 31b of the unit 30 that generates a B-phase standing wave. In addition, since the wave generated when the AC voltage is applied only to the unit 30 that generates the A-phase standing wave is a standing wave, the positions of the peaks, valleys, and nodes do not change, and their amplitudes do not change. Only changes.

  On the other hand, when the AC voltage is applied only to the unit 30 that generates the B-phase standing wave, the standing wave B is generated in the cells 31 in the X1 row. Specifically, the positions of the peaks and valleys of the standing wave B waveform are the positions of the cells 31a and 31b of the unit 30 that generates the B-phase standing wave, and the positions of the nodes of the standing wave B waveform. Are the positions of the cells 31a and 31b of the unit 30 that generate the A-phase standing wave. In addition, since the wave generated when the AC voltage is applied only to the unit 30 that generates the B-phase standing wave is also a standing wave, the positions of the peaks, valleys, and nodes do not change, and their amplitudes do not change. Only changes. Further, the standing wave A and the standing wave B are different from each other in the positions of peaks, valleys, and nodes by 90 °. This is because, as described above, the interval between the unit 30 that generates the A-phase standing wave and the unit 30 that generates the B-phase standing wave is spatially 90 ° apart.

  When alternating voltages that differ by + 90 ° or −90 ° in time are applied simultaneously to the unit 30 that generates the A-phase standing wave and the unit 30 that generates the B-phase standing wave, respectively, A combined wave of the standing wave A and the standing wave B becomes a traveling wave. This traveling wave travels in the X-axis positive direction or the X-axis negative direction according to the phase shift direction of the AC voltage, and is also generated on the one main surface of the track pad 2. In the above description, the cells 31 arranged in the X1 row are used, but it goes without saying that the same traveling wave is generated even in the cells 31 arranged in other rows even if the polarities are different. That is, a traveling wave in one direction is generated on the entire surface of the one main surface of the track pad 2.

  In addition, when driving in the vertical direction (Y-axis direction), the unit 30 that generates the A-phase standing wave and the unit 30 that generates the B-phase standing wave are changed. As shown in FIG. 7, when driving in the vertical direction, the units 30 arranged in odd rows on the entire other main surface of the track pad 2 generate A-phase standing waves, and the entire other main surface of the track pad 2. Units 30 arranged in even-numbered rows generate a B-phase standing wave. Also in this case, the phase generated by the unit 30 that generates the A-phase standing wave and the phase generated by the unit 30 that generates the B-phase standing wave are arranged 90 ° apart from each other. Become.

As described above, the drive circuit 12 differs from the unit 30 that generates the A-phase standing wave and the unit 30 that generates the B-phase standing wave by + 90 ° or −90 ° in time. An AC voltage of two systems (hereinafter sometimes referred to as A system and B system) is applied. That is, the unit 30 to which the drive circuit 12 applies the AC voltage of the A system and the B system is different between the vertical driving and the horizontal driving. For example, when switching between the A phase and B phase in the vertical direction (see FIG. 7) and the A phase and B phase in the horizontal direction (see FIG. 5) in a time-sharing manner, the drive circuit 12 includes the A system and the B system. The switching of the target to which each AC voltage is applied is also performed in a time-sharing manner.

  As an example, the drive circuit 12 includes a circuit for generating AC voltage for the A system and B system for vertical driving and a circuit for generating AC voltage for the A system and B system for horizontal driving, respectively. To do. In this case, the drive circuit 12 has a function of generating four systems of AC voltages. And the control part 1 selects the circuit which outputs an alternating voltage in the drive circuit 12 suitably, and controls it.

  As another example, the drive circuit 12 performs time-division switching for the unit 30 that generates an A-phase standing wave in the vertical direction and the unit 30 that generates an A-phase standing wave in the horizontal direction. The AC voltage of the same A system is applied. The drive circuit 12 switches in a time-division manner to the unit 30 that generates a B-phase standing wave in the vertical direction and the unit 30 that generates a B-phase standing wave in the horizontal direction. Apply an alternating voltage. In this case, the drive circuit 12 has a function of generating two systems of AC voltages, and the control unit 1 appropriately selects and controls the switching.

  Here, in FIG. 6, the standing wave focused on the one row of cells 31 arranged in parallel in the X-axis direction has been described. However, in the longitudinal drive, the same standing wave is generated in a manner in which the vertical and horizontal directions in FIG. 6 are switched. It is clear that this will occur. That is, in the longitudinal drive, the same standing wave A and standing wave B are generated for the cells 31 arranged in parallel in the Y-axis direction. Even in the longitudinal driving, AC voltages that differ by + 90 ° or −90 ° in time are applied to the unit 30 that generates the A-phase standing wave and the unit 30 that generates the B-phase standing wave, respectively. Since they are applied simultaneously, the combined wave of the standing wave A and the standing wave B becomes a traveling wave. This traveling wave travels in the Y-axis positive direction or the Y-axis negative direction according to the phase shift direction of the AC voltage, and is also generated on the surface of one main surface of the track pad 2. That is, by controlling the AC voltage applied from the drive circuit 12, a traveling wave in the vertical direction or the horizontal direction can be generated on the entire surface of one main surface of the track pad 2.

  Next, using FIG. 8 to FIG. 10, the force that the traveling wave generated on the track pad 2 gives to the finger of the user who is touching the track pad 2 will be described. FIG. 8 is an enlarged cross-sectional view showing a part of a contact portion between a traveling wave generated on the track pad 2 and a user's finger touching the track pad 2. FIG. 9 is an enlarged cross-sectional view of the track pad 2 showing a state where the traveling wave has advanced from the state of FIG. 8 by ¼ period. FIG. 10 is an enlarged cross-sectional view of the track pad 2 showing a state in which the traveling wave has advanced from the state of FIG.

  8 to 10, alternately polarized piezoelectric elements (cells 31 a and 31 b) are bonded to the lower surface of the track pad 2, and a high-frequency voltage such as an alternating voltage is applied to the piezoelectric elements. As a result, the piezoelectric element is caused to expand and contract as described above, and a traveling wave traveling in a predetermined direction is excited on the surface of the track pad 2. 8 to 10 show examples in which a traveling wave travels from the left to the right of the page with respect to the track pad 2.

  Here, attention is paid to one protrusion 21 formed on the surface of the track pad 2. The protrusion 21 vibrates up and down in response to excitation of traveling wave vibration, but strictly, it vibrates along an elliptical locus T. More specifically, the protrusion 21 performs an elliptical motion in the opposite direction (counterclockwise) with respect to the traveling direction of the traveling wave (from left to right in the drawing). By this elliptical motion, a friction force opposite to the traveling direction of the traveling wave is generated on the user's finger in contact with the protrusion 21 formed at the traveling wave peak by applying pressure to the protrusion 21. Thus, it can be seen that the protrusion 21 also has a function of enlarging a minute displacement excited by traveling wave vibration. Further, as described above, since the traveling wave traveling in both the longitudinal direction and the lateral direction can be excited on the surface of the track pad 2, the frictional force is generated in all directions along the surface of the track pad 2. It is possible to make it.

  For example, when the user is touching an arbitrary position on the track pad 2 with a finger in a neutral state where the touch position is not fixed, the user can move the track pad 2 in the direction in which the frictional force is generated when the traveling wave vibration is excited. The finger is guided. Hereinafter, the direction in which the frictional force is generated is referred to as a guidance direction. Further, when the user is trying to perform an operation of tracing in a predetermined direction while touching the track pad 2 (hereinafter, the touch operation is described as a slide operation, and the tracing direction is described as a slide direction), the slide direction The above frictional force is generated with the direction opposite to the induction direction. In this case, the force that the user receives from the surface of the operation surface of the track pad 2 is that the user's finger is guided in the direction opposite to the sliding direction, but the force that hinders the user's sliding operation, that is, the reaction force It can also be considered that this is generated on the operation surface. Further, when the user's finger is guided in the sliding direction, it can be considered that a force for propelling the user's sliding operation, that is, a thrust is generated on the operation surface. That is, the input device of the present invention may guide a user's finger touching the track pad 2 in a predetermined direction along the operation surface of the track pad 2 or generate a reaction force or a thrust against a slide operation. it can.

  In addition, the magnitude of the induction force, thrust force, reaction force, etc. generated on the user's finger along the operation surface of the track pad 2 and the speed in the induction direction are the voltage, current, and frequency applied to the piezoelectric element 30 by the drive circuit 12. Each of them can be adjusted by controlling the above.

  Next, a control example for guiding the touch position where the user touches the track pad 2 will be described with reference to FIGS. FIG. 11 is a diagram illustrating a first example of controlling to guide the user's touch position TP. FIG. 12 is a diagram illustrating a second example of controlling to guide the user's touch position TP. FIG. 13 is a diagram illustrating a third example of controlling to guide the user's touch position TP. In addition, although the mark showing a hand is described in FIGS. 11-13, this represents typically the hand of the user who performs a touch operation.

  In FIG. 11, the cursor C is displayed at the designated position TPd on the display screen of the external device 9 according to the touch position TP where the user touches the track pad 2. For example, the external device 9 uses the position data of the touch coordinate system (coordinate data of the touch position TP) of the track pad 2 output from the input device as the position data of the display coordinate system (the designated position TPd) set on the display screen. By converting the coordinates into (coordinate data), the position of the cursor C displayed on the display screen can be calculated.

  Also, one display button image B1 is displayed on the display screen of the external device 9. The external device 9 determines that the user has selected the option described in the display button image B1 by touching the position of the corresponding trackpad 2 in the display area of the display button image B1. In the example shown in FIG. 11, only one display button image B1 described as “OK” is displayed, and the user has one option.

In such a case, the input device guides the user's touch position TP so that the user touches the position of the corresponding trackpad 2 in the display area of the display button image B1. For example, the CPU 10 sets the position of the track pad 2 corresponding to the center of the display area of the display button image B1 as the guidance target position M1, and proceeds with the direction dir1 from the current touch position TP toward the guidance target position M1 as the guidance direction. A wave is generated on the trackpad 2. As a result, the user's finger is guided along the track pad 2 to the guidance target position M1. Then, the external device 9 determines that the user has selected the option described in the display button image B1 when the designated position TPd corresponding to the touch position TP of the user has moved to the display area of the display button image B1. For example, even when only one option is displayed, the user may not be able to find the touch position corresponding to the option because the user cannot visually recognize the operation surface of the track pad 2. As long as the user touches the operation surface, the user's touch operation can be appropriately guided.

  Also in the second example of controlling to guide the touch position TP shown in FIG. 12, the cursor C is displayed at the designated position TPd on the display screen of the external device 9 according to the touch position TP where the user touches the track pad 2. Is done. In addition, two display button images B2 and B3 are displayed on the display screen of the external device 9. The external device 9 determines that the user has selected the option described in the display button image B2 or B3 by touching the position of the corresponding trackpad 2 in the display area of the display button image B2 or B3. To do. In the example shown in FIG. 12, the display button image B2 described on the button “OK” and the display button image B3 described on the button “Cancel” are displayed, and the user has two options. It is.

  In such a case, the input device touches the position of the trackpad 2 corresponding to the display area closer to the current designated position TPd among the display areas of the display button images B2 and B3. Induces TP. For example, the CPU 10 sets the position of the track pad 2 corresponding to the center of the display area of the display area closer to the current indicated position TPd from the display areas of the display button images B2 and B3 as the guidance target position. In the example of FIG. 12, since the display area of the display button image B2 is close to the current designated position TPd, the position of the track pad 2 corresponding to the center of the display area of the display button image B2 is set as the guidance target position M2. Then, a traveling wave is generated on the track pad 2 with the direction dir2 from the current touch position TP toward the guidance target position M2 as the guidance direction. As a result, the user's finger is guided along the track pad 2 to the guidance target position M2. Then, the external device 9 determines that the user has selected the option described in the display button image B2 when the designated position TPd corresponding to the touch position TP of the user has moved to the display area of the display button image B2. For example, when two options are displayed, the user can select the option selected by the user only by touching the operation surface of the trackpad 2 corresponding to the vicinity of the position where the option selected by the user is displayed. Touch operation can be guided.

  Also in the third example of controlling to guide the touch position TP shown in FIG. 13, the cursor C is displayed at the designated position TPd on the display screen of the external device 9 according to the touch position TP where the user touches the track pad 2. Is done. In addition, five display button images B4 to B8 are displayed on the display screen of the external device 9. The external device 9 allows the user to select options described in the display button images B4 to B8 when the user touches the position of the corresponding trackpad 2 in any one display area of the display button images B4 to B8. Judge that selected. In the example shown in FIG. 13, display button image B4 described as “1”, display button image B5 described as “2”, display button image B6 described as “3”, and “4” are described. The display button image B7 and the display button image B8 described as “5” are displayed side by side, and there are five options for the user.

In such a case, the input device touches the position of the trackpad 2 corresponding to the position within the display area closest to the current designated position TPd among the display areas of the display button images B4 to B8. To induce. For example, the CPU 10 sets the position of the track pad 2 corresponding to the center of the display area of the display area closest to the current designated position TPd from any one of the display areas of the display button images B4 to B8 as the guidance target position. In the example of FIG. 13, since the display area of the display button image B5 is closest to the current designated position TPd, the position of the track pad 2 corresponding to the center of the display area of the display button image B5 is set as the guidance target position M5. . Then, a traveling wave is generated on the track pad 2 with the direction dir3 from the current touch position TP toward the guidance target position M5 as the guidance direction. Accordingly, the user's finger is guided along the track pad 2 to the guide target position M5. The external device 9 then detects the user's touch position T
When the designated position TPd corresponding to P moves to the display area of the display button image B5, it is determined that the user has selected an option described in the display button image B5. For example, when three or more options are displayed, the user can select an option by touching the operation surface of the trackpad 2 corresponding to the vicinity of the position where the option selected by the user is displayed on the input device. The touch operation to select can be guided.

  Here, there are cases where the user performs a slide operation by sequentially changing the options in the order of “1” → “2” → “3” → “4” → “5”. For example, when changing the volume / sound quality of an audio device or the setting mode of the device, the user generally changes the setting level or setting mode continuously.

  For example, when the designated position TPd is within the display area of the display button image B5, the position of the track pad 2 corresponding to the center of the display area of the display button image B5 is set as the guidance target position M5. Then, as long as the designated position TPd is in the state closest to the display area of the display button image B5, the user's finger is guided along the track pad 2 to the guidance target position M5.

  Next, when the user performs a slide operation to change the option from “2” to “3”, the designated position TPd corresponding to the touch position TP moves from the display area of the display button image B5 to the display area of the display button image B6. Move towards. At this time, if the designated position TPd is closer to the display area of the display button image B5 than the display image of the display button image B6, the user's finger is guided along the track pad 2 to the guidance target position M5. That is, the user's finger is guided along the track pad 2 in the opposite direction to the slide direction to change from the option “2” to “3”, and a reaction force of the slide operation is generated.

  Thereafter, when the user continues the sliding operation against the reaction force and the designated position TPd moves from the display image of the display button image B5 to a position closer to the display area of the display button image B6, the display area center of the display button image B6 is displayed. Is set to the guidance target position M6. Then, the user's finger is guided along the track pad 2 to the guidance target position M6. That is, the user's finger is guided along the track pad 2 in the same direction as the sliding direction in which the option “2” is changed to “3”.

  As described above, when the user performs a slide operation to change the option from “2” to “3”, a thrust for the slide operation is applied to the user's finger after a reaction force to the slide operation is applied. Therefore, in the user's slide operation on the operation surface of the track pad 2, a moderation feeling corresponding to the display button is born, and the user can see that the button touched by the touch of the finger is changed. It is also useful to avoid operations such as touching the neutral region between the display buttons.

  Further, since the display button images B4 to B8 are displayed side by side, the guidance target positions set for the display button images B4 to B8 are arranged in parallel in the vertical direction of the track pad 2 (FIG. 13). Guide target positions M4 to M8) shown in FIG. In such a display button arrangement, when the user performs a sliding operation in the horizontal direction on the track pad 2, the user's finger is guided in a direction toward any of the guide target positions M4 to M8. Are guided on the parallel line of the guide target positions M4 to M8. Therefore, the user can intuitively understand that the option can be selected by sliding the above parallel line with a finger. As a result, the user's touch operation that slides in an inappropriate slide direction for selecting an option can be guided in an appropriate direction, and the user's operability can be improved.

Next, specific processing operations executed by the control unit 1 of the input device will be described with reference to FIGS. 14 and 15. FIG. 14 is a diagram illustrating an example of various data stored in the storage unit 11. FIG. 15 is a flowchart illustrating an example of an operation in which the control unit 1 performs processing. For example, each data shown in FIG. 14 is stored in the storage unit 11 as appropriate by the CPU 10 executing a program or acquiring it from the external device 9. Each step of the flowchart shown in FIG. 15 is performed by the CPU 10 executing the above program. Note that a program for executing these processes is stored in advance in the storage unit 11, for example, and is executed by the CPU 10 when the input device is turned on.

  In FIG. 14, the storage unit 11 stores temporary data generated in the processing of the CPU 10. The storage unit 11 stores touch position data Da, guidance target position data Db, traveling wave direction data Dc, display button data Dd, cursor data De, and the like.

  The touch position data Da indicates the touch position TP where the user touches the operation surface of the track pad 2 and is data that is updated as appropriate based on the coordinate data output by the touch sensor 20. The guidance target position data Db is data indicating a guidance target position M for guiding the finger touched by the user along the track pad 2. The traveling wave direction data Dc is data indicating a direction in which a traveling wave for guiding the finger touched by the user to the guidance target position M along the track pad 2 is generated on the operation surface of the track pad 2.

  The display button data Dd is data related to the display button displayed on the display screen of the external device 9, and the instruction content data Dda, the button area data Ddb, the button center position data Ddc, the display button image data Ddd, and the like are displayed on the display button. Includes every. The instruction content data Dda is data indicating the contents of options that are instructed when the user selects a display button. The button area data Ddb is screen coordinate system data indicating the position of the entire area where the display button is displayed. The button center position data Ddc is data in the screen coordinate system indicating the center position of the area where the display button is displayed. The display button image data Ddd is image data for displaying the display button on the display screen.

  The cursor data De is data related to the cursor C displayed on the display screen of the external device 9, and includes designated position data Dea, cursor image data Deb, and the like. The designated position data Dea is data indicating the designated position TPd corresponding to the touch position TP indicated by the touch position data Da. The cursor image data Deb is image data for displaying the cursor C on the display screen.

  First, when a power source (not shown) of the input device is turned on, a program stored in the storage unit 11 is executed by the CPU 10. And CPU10 performs each step shown in FIG. 15 based on the said program.

  In FIG. 15, the CPU 10 performs an initial setting process (step S51) and advances the process to the next step. For example, as an initial setting performed by the CPU 10 in step S51, the CPU 10 initializes various data stored in the storage unit 11. Then, the CPU 10 sets the display button data Dd, and displays the display button image B corresponding to each display button data Dd on the display screen of the external device 9. For example, the CPU 10 arranges the display button image B in the virtual world so that those areas are arranged at the position of the display coordinate system indicated by the button area data Ddb, and displays the virtual world on the display screen.

Next, CPU10 detects the touch output from the touch sensor 20 according to a user's touch operation (step S52), and waits for a touch output (step S53). When the touch output from the touch sensor 20 is detected (Yes in step S53), the CPU 10
The coordinate data indicating the touch position TP touching the operation surface of the track pad 2 is acquired from the touch sensor 20, the touch position data Da is updated to the coordinate data, and the process proceeds to the next step.

  Next, the CPU 10 calculates an instruction position TPd corresponding to the touch position TP (step S54), and advances the processing to the next step. Specifically, the CPU 10 converts the coordinate data of the touch coordinate system (coordinate data of the touch position TP) stored as the touch position data Da into coordinate data of the display coordinate system set on the display screen. The coordinate data of the designated position TPd is calculated. Then, the CPU 10 updates the designated position data Dea to the calculated coordinate data of the designated position TPd.

  Next, the cursor C is displayed on the display screen of the external device 9 according to the designated position TPd (step S55), and the process proceeds to the next step. For example, the CPU 10 arranges the cursor C in the virtual world so that the tip thereof is arranged at the position of the display coordinate system indicated by the designated position TPd, and displays the virtual world on the display screen together with the display button image B. (See FIGS. 11 to 13).

  Next, the CPU 10 extracts the display button area closest to the designated position TPd, sets the guidance target position M (step S56), and advances the processing to the next step. For example, the CPU 10 refers to the button area data Ddb set for each display button displayed on the display screen, and extracts the display button displayed closest to the designated position TPd. Then, the CPU 10 converts the center position of the area indicated by the button center position data Ddc set for the extracted display button into the touch coordinate system, and sets the coordinate-converted position as the guidance target position M. Thus, the guidance target position data Db is updated.

  Next, the CPU 10 excites a traveling wave having a guidance direction in a direction from the touch position TP toward the guidance target position M (see directions dir1 to dir3 shown in FIGS. 11 to 13) on the operation surface of the track pad 2. (Step S57). For example, the CPU 10 refers to the touch position data Da and the guidance target position data Db, and is in a direction opposite to the guidance direction from the touch position TP toward the guidance target position M (that is, from the guidance target position M toward the touch position TP). Direction). Then, the CPU 10 updates the traveling wave direction data Dc by setting the calculated direction as the traveling direction in which the traveling wave travels on the operation surface of the track pad 2. Then, the CPU 10 controls the drive circuit 12 so that the traveling wave traveling in the traveling direction is excited on the operation surface of the track pad 2. For example, as described above, the CPU 10 causes the target unit 30 (A phase and B phase) to which the drive circuit 12 applies the AC voltage of the A system and the B system, respectively, during the vertical driving and the horizontal driving. The generation of traveling waves traveling in the vertical direction and the horizontal direction is controlled by controlling to change by division.

  Next, the CPU 10 determines whether or not the designated position TPd is within the display area of the display button (step S58). For example, the CPU 10 refers to the respective button area data Ddb set for the display button displayed on the display screen, and determines whether or not the designated position TPd is within the display area of any display button. If the designated position TPd is not within any display area of the display button, the CPU 10 returns to step S52 and repeats the process. On the other hand, if the designated position TPd is within any display area of the display button, the CPU 10 advances the process to the next step S59.

In step S59, the CPU 10 selects, as an input instruction, an instruction indicated by the display button including the instruction position TPd in the display area, and advances the processing to the next step. For example, the CPU 10 refers to the instruction content data Dda set to the display button including the instruction position TPd, and outputs the option indicated by the instruction content data Dda to the external device 9 or the like as an input instruction from the user.

  Next, the CPU 10 determines whether or not to end the process (step S60). Then, the CPU 10 returns to step S52 when the process is continued, repeats the process, and ends the process according to the flowchart when the process is ended.

  Thus, according to the input device according to the present embodiment, the operability of the user is improved by generating a force for guiding the user's finger according to the touch position on the operation surface of the trackpad on which the user performs a touch operation. Can be improved. In addition, when a slide operation is assumed on the operation surface of the input device, a thrust or reaction force in the slide direction is applied to the user's finger according to a plurality of display button positions. Therefore, in the user's slide operation on the operation surface, a sense of moderation according to the display button is born, and the user can see that the touching button is changed by the touch of the finger, so that the user touches the neutral area between the display buttons. Can be avoided.

  In addition, the shape of the track pad 2 described above, the shape, the number, the attachment position, the polarization number, and the like of the piezoelectric element 30 provided thereon are merely examples, and other shapes, numbers, attachment positions, It goes without saying that the present invention can be realized even with the number of polarizations. For example, the piezoelectric element 30 includes 8 × 8 cells 31 as one unit, but it is sufficient that one unit is configured by 2 × 2 or more cells 31, and 8 × 8 or more cells 31 are formed. It may be configured as one unit. The gap G between the units was formed by alternately repeating a half width of the full width of the cell 31 and a width of 1.5 times the full width of the cell 31, but the unit generating the A-phase standing wave and the B If the phases generated by the units that generate the standing waves of the phases are arranged 90 ° apart in both the vertical and horizontal directions, the gap G may be formed with another width.

  The program stored in the storage unit 11 may be supplied to the input device through an external storage medium such as an optical disk or a nonvolatile semiconductor memory, or may be supplied to the input device through a wired or wireless communication line.

  Further, in the processing operation executed by the control unit 1 described above, an example in which the CPU 10 performs display control on the display device of the external device 9 and an option determination operation is also used, but a function of simply outputting input information to the external device 9 However, an input device having only the above may be used. In this case, the input device outputs coordinate data obtained by the user touching the track pad 2 to the external device 9, and information for calculating the position of the touch coordinate system indicating the guidance target position and the guidance target position (for example, all The position of the touch coordinate system corresponding to the display button, the position of the touch coordinate system corresponding to the display button closest to the touch position, etc.) are acquired from the external device 9 and the above-described processing operation is performed.

  Further, in the processing operation executed by the control unit 1 described above, the position of the track pad 2 corresponding to the center position of the display button is set as the guidance target position, but another position may be set as the guidance target position. It doesn't matter. For example, the position of the track pad 2 corresponding to a point on the outline of the display button closest to the indicated position or another point inside the display button may be set as the guidance target position.

  In the processing operation executed by the control unit 1 described above, the position of the track pad 2 corresponding to the position of the center of the display button closest to the indicated position is set as the guidance target position. The position may be set as the guidance target position. For example, the learning function may be provided in the input device or the external device 9, and the position of the track pad 2 corresponding to the center position of the display button normally selected by the user may be set as the guidance target position. Further, the position of the track pad 2 corresponding to the center position of the display button indicating the option to be selected by the user may be set as the guidance target position.

  Furthermore, the guide target position may be fixedly set at a predetermined position such as the center of the operation surface of the track pad 2. In this case, the user will always be guided to the predetermined position (for example, the center position) where the track pad 2 is fixed, and the user can always recognize the predetermined position of the track pad 2 with a touch feeling. it can.

  In addition, the track pad 2 may be a device of another aspect as long as the input device performs an input operation by a user touching the operation surface. For example, other pointing devices such as a tablet and a touch panel may be used.

  The processing operation executed by the control unit 1 described above is realized by the CPU 10 executing a program. However, other devices such as a circuit that implements the processing operation described above are configured in the control unit 1. It may be realized by configuration. For example, the control unit 1 described above can be realized by configuring a circuit that receives a coordinate signal corresponding to the touch position and a coordinate signal indicating the guidance target position and outputs an AC voltage from the drive circuit 12 to the piezoelectric element 30. is there.

  The input device according to the present invention can give a tactile sensation for guiding the touch input position to a predetermined touch position when the user is performing a touch input operation. The present invention can be applied to uses such as a trackpad (touch pad), tablet, touch panel, etc. for performing input operations.

The block diagram which shows schematic structure of the input device which concerns on one Embodiment of this invention. Sectional drawing which shows the internal structure of the trackpad 2 of FIG. 1 is a plan view showing the structure of a piezoelectric element 30 disposed on the track pad 2 of FIG. The figure which shows the alternating voltage connection example with respect to the some cell 31 of FIG. The top view which shows the example of arrangement | positioning of the unit 30 which generates the standing wave of A phase, and the unit 30 which generates the standing wave of B phase at the time of a horizontal direction drive The figure explaining an example of the standing wave which generate | occur | produces at the time of a horizontal direction drive The top view which shows the example of arrangement | positioning of the unit 30 which generates the standing wave of A phase, and the unit 30 which generates the standing wave of B phase at the time of longitudinal direction drive 1 is an enlarged cross-sectional view showing a part of a contact portion between a traveling wave generated on the track pad 2 of FIG. 1 and a user's finger touching the track pad 2. 8 is an enlarged cross-sectional view of the track pad 2 showing a state in which the traveling wave has advanced by a quarter period from the state of FIG. FIG. 9 is an enlarged cross-sectional view of the track pad 2 showing a state where a traveling wave has advanced from the state of FIG. 8 by ½ period. The figure which shows the 1st example which carries out the control which guide | induces a user's touch position TP. The figure which shows the 2nd example which controls to induce | guide | derive a user's touch position TP. The figure which shows the 3rd example which controls to induce | guide | derive a user's touch position TP. The figure which shows an example of the various data memorize | stored in the memory | storage part 11 of FIG. The flowchart which shows an example of the operation | movement which the control part 1 of FIG. 1 performs a process.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Control part 10 ... CPU
DESCRIPTION OF SYMBOLS 11 ... Memory | storage part 12 ... Drive circuit 13, 14 ... I / O
2 ... track pad 20 ... touch sensor 21 ... projection 3 ... traveling wave generator 30 ... piezoelectric element (unit)
31 ... cell 9 ... external device

Claims (10)

An input device for inputting input information,
Operation surface,
A contact position detection unit that detects, as the input information, a contact position of an object in contact with the operation surface;
A control unit for setting a guidance target for guiding the contact position on the operation surface;
An input device, comprising: a force generation unit that applies a force along the operation surface to the object in contact with the operation surface in a direction from the contact position toward the guidance target.   The input device according to claim 1, wherein the control unit sets the guidance target at a position on the operation surface corresponding to a display position of a display button displayed on a display screen.   The control unit selects a display button closest to the indicated position on the display screen corresponding to the contact position from among the plurality of display buttons displayed on the display screen, and corresponds to the display position of the display button. The input device according to claim 2, wherein the guidance target is set at a position on the operation surface. The operation surface is configured on the surface of an elastic plate member,
The force generation unit follows the operation surface in the direction from the contact position toward the guidance target by exciting the elastic plate-like member to travel in the direction from the guidance target toward the contact position. The input device according to claim 1, wherein a force is applied to the object. The force generator is
Piezoelectric elements that are affixed to the entire back surface of the elastic plate-like member and polarized in a lattice pattern;
A voltage supply unit for supplying positive and negative alternating high-frequency voltages to each electrode of the polarized piezoelectric element,
The said control part contains the voltage supply control part which controls the high frequency voltage which the said voltage supply part supplies so that the said traveling wave may advance in the direction which goes to the said contact position from the said guidance target. Input device. The piezoelectric element has a plurality of units including a plurality of the electrodes,
The unit is
A first unit group that generates a first standing wave in the elastic plate member by being supplied with a high-frequency voltage from the voltage supply unit;
The second standing wave is disposed at a position 90 degrees away from the first unit group in the phase of the first standing wave, and the second standing wave is supplied to the elastic plate by being supplied with a high frequency voltage from the voltage supply unit. Divided into a second unit group to be generated in the member,
The voltage supply unit supplies a first system high-frequency voltage to the first unit group, and supplies a second system high-frequency voltage having a phase different from that of the first system high-frequency voltage to the second unit group. ,
The said voltage supply control part controls the phase of the high frequency voltage of the said 1st system and the high frequency voltage of the said 2nd system which the said voltage supply part supplies according to the direction which advances the said traveling wave, The input device described. The unit is
A third unit group that causes the elastic plate member to generate a third standing wave that is generated in a direction orthogonal to the direction in which the first standing wave is generated by being supplied with a high-frequency voltage from the voltage supply unit;
The fourth unit is disposed at a position 90 degrees away from the third unit group in the phase of the third standing wave, and is supplied with a high frequency voltage from the voltage supply unit, whereby the fourth standing wave is transmitted to the elastic plate. Further divided into a fourth unit group to be generated in the member,
The voltage supply unit further supplies the high frequency voltage of the first system to the third unit group, and supplies the high frequency voltage of the second system to the fourth unit group,
The voltage supply control unit supplies a high-frequency voltage to a set of the first unit group and the second unit group according to a direction in which the traveling wave travels, and the third unit group and the fourth unit. The input device according to claim 6, wherein the time for supplying the high-frequency voltage to the group set is controlled in a time-sharing manner.   The input device according to claim 1, wherein when the object moves while contacting the operation surface, the force generation unit applies a thrust to the object in the moving direction.   The input device according to claim 1, wherein when the object moves while contacting the operation surface, the force generation unit applies a reaction force to the object in the moving direction. An input device for inputting input information,
An elastic plate-like member constituting an operation surface on the surface;
A contact position detection unit that detects, as the input information, a contact position of an object in contact with the operation surface;
Piezoelectric elements that are affixed to the entire back surface of the elastic plate-like member and polarized in a lattice pattern;
An input device comprising: a voltage supply unit configured to supply a positive and negative alternating high-frequency voltage to each electrode of the polarized piezoelectric element to excite a traveling wave in the elastic plate member.

Images