Vibration generating devices and electronic equipment
By forming multiple concave and convex structures on the first main surface of the vibrator and using high-frequency drive signals, the contact sound problem of the vibration generating device during contact is solved, and the combination of tactile feedback and light transmittance is realized.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- TAIYO YUDEN KK
- Filing Date
- 2021-03-01
- Publication Date
- 2026-07-31
AI Technical Summary
In the prior art, vibration generating devices are prone to producing contact sounds when fingers touch the panel, and surface roughening treatment may affect light transmittance.
Multiple concave and convex structures are formed at equal intervals on the first main surface of the vibrating body, and a drive signal of more than 60kHz is supplied to the piezoelectric actuator through a drive device to prevent the generation of contact sound and maintain light transmittance.
It effectively suppresses the generation of contact sound, while providing tactile feedback and maintaining the light transmittance of the vibrating body.
Smart Images
Figure CN115279505B_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to vibration generating devices and electronic devices in connection with tactile cues based on vibration. Background Technology
[0002] Touch panels in smartphones or car navigation systems use a technique that uses vibration to notify of input (force feedback). In recent years, research has been underway on tactile technologies that go beyond simply notifying users; they also explore techniques that use variations in panel vibration to represent the tactile sensation of an object or to identify the location of an operation.
[0003] As a tactile technology, piezoelectric actuators can be attached to a panel, generating standing waves on the panel surface by causing vibrations in the ultrasonic frequency band. Users can feel the touch when they touch the surface with their fingers or other objects. Furthermore, by changing the signal mode, various tactile sensations can be represented.
[0004] However, when a finger touches the panel surface that produces this tactile sensation, it can cause rattling (hereinafter, contact noise) due to the contact between the finger and the panel. To address this, Patent Document 1 proposes a method whereby, for the generated sound, a suppressing sound at a higher frequency is generated, and the suppression effect of the two sounds is used to reduce the perceived contact noise. Furthermore, Patent Document 2 suggests a method to reduce contact noise by coarsening the surface roughness of the panel surface.
[0005] Existing technical documents
[0006] Patent documents
[0007] Patent Document 1: Japanese Patent Application Publication No. 2018-194967
[0008] Patent Document 2: Japanese Patent Application Publication No. 2019-16111 Summary of the Invention
[0009] The technical problem that the invention aims to solve
[0010] However, in the technology described in Patent Document 1, the generation of contact sound is not suppressed. Furthermore, in the technology described in Patent Document 2, the continuity of the surface unevenness is not mentioned.
[0011] In view of the above, the object of the present invention is to provide a vibration generating device and electronic device that can prevent the generation of contact sound and provide tactile feedback.
[0012] Technical solutions for solving technical problems
[0013] To achieve the above objectives, one aspect of the vibration generating device of the present invention includes a vibrating body and a piezoelectric actuator.
[0014] The vibrating body has a first principal surface and a second principal surface opposite to the first principal surface.
[0015] The piezoelectric actuator described above is coupled to the second main surface described above.
[0016] Multiple irregularities are formed at equal intervals on the first main surface.
[0017] According to this structure, by forming uneven surfaces at equal intervals on the first main surface of the vibrator, the contact between the user's finger and the first main surface is discontinuous, which can provide the user's finger with tactile feedback and prevent the generation of contact sound.
[0018] Alternatively, the depth of the aforementioned multiple protrusions and concavities may be greater than 0.01mm and less than 0.1mm, and the width may be greater than 1mm and less than 10mm.
[0019] Alternatively, the aforementioned plurality of concave and convex portions may be alternately formed by a plurality of concave portions extending along a first direction parallel to the aforementioned first main surface and a plurality of convex portions extending along the aforementioned first direction.
[0020] Alternatively, the aforementioned plurality of concave and convex shapes may also be formed by alternating plurality of concave portions extending along a second direction parallel to the first main surface and different from the first direction, and plurality of convex portions extending along the second direction.
[0021] Alternatively, the cross-sectional shape of the aforementioned plurality of concave and convex features in a plane perpendicular to the aforementioned first direction may have a sinusoidal shape.
[0022] Alternatively, the vibrator may be made of glass or a resin material with a flexural modulus of 3.0 GPa or higher.
[0023] Alternatively, the vibrator may be composed of a substrate and a film adhered to the surface of the substrate, with the aforementioned irregularities formed on the surface of the film.
[0024] Alternatively, the vibrating body described above may have light transmittance.
[0025] To achieve the above objectives, one aspect of the present invention provides an electronic device that has a vibration generating device.
[0026] The vibration generating device includes: a vibrating body having a first main surface and a second main surface opposite to the first main surface; and a piezoelectric actuator coupled to the second main surface, having a plurality of protrusions and recesses formed at equal intervals on the first main surface.
[0027] To achieve the above objectives, one aspect of the vibration generating device of the present invention includes a vibrating body, a piezoelectric actuator, and a driving device.
[0028] The vibrating body has a first principal surface and a second principal surface opposite to the first principal surface.
[0029] The piezoelectric actuator described above is coupled to the second main surface described above.
[0030] The aforementioned driving device supplies the aforementioned piezoelectric actuator with a driving signal of frequency of 60kHz or higher.
[0031] Based on this structure, the vibration at 1 / 4 frequency that causes the contact sound between the finger and the vibrating body becomes a vibration above 15kHz, which is outside the human audible frequency band, thus preventing the generation of contact sound.
[0032] Alternatively, the vibrator may be made of glass or a resin material with a flexural modulus of less than 3.0 GPa.
[0033] To achieve the above objectives, one aspect of the present invention provides an electronic device that has a vibration generating device.
[0034] The vibration generating device includes: a vibrating body having a first main surface and a second main surface opposite to the first main surface; a piezoelectric actuator coupled to the second main surface; and a driving device that supplies a driving signal with a frequency of 60 kHz or higher to the piezoelectric actuator.
[0035] Alternatively, the vibration generating device may also include a driving device, which supplies a driving signal with a frequency of 60 kHz or higher to the piezoelectric actuator.
[0036] Invention Effects
[0037] According to the present invention as described above, a vibration generating device and electronic device that can prevent the generation of contact noise and provide tactile feedback can be provided. Attached Figure Description
[0038] Figure 1 This is a schematic diagram of a vibration generating device according to an embodiment of the present invention.
[0039] Figure 2 This is a three-dimensional view of the aforementioned vibration generating device.
[0040] Figure 3 This is a side view of the aforementioned vibration generating device.
[0041] Figure 4 This is a three-dimensional view of the vibrating body of the aforementioned vibration generating device.
[0042] Figure 5 This is a top view of the aforementioned vibrating body.
[0043] Figure 6This is a side view of the vibrating body described above.
[0044] Figure 7 This is a graph showing the sound pressure characteristics of the vibrating body in the comparative example.
[0045] Figure 8 This is a graph showing the vibration displacement of the vibrating body in the comparative example.
[0046] Figure 9 This is a graph showing the sound pressure characteristics of the vibrating body of the vibration generating device according to an embodiment of the present invention.
[0047] Figure 10 This is a graph representing the vibration displacement of the aforementioned vibrating body.
[0048] Figure 11 This is a top view showing a vibrating body with other structures according to an embodiment of the present invention.
[0049] Figure 12 This is a top view showing a vibrating body with other structures according to an embodiment of the present invention.
[0050] Figure 13 This is a side view of a vibrating body having other structures, illustrating an embodiment of the present invention.
[0051] Figure 14 This is a side view of a vibrating body having other structures, illustrating an embodiment of the present invention.
[0052] Figure 15 This is a side view of a vibrating body having other structures, illustrating an embodiment of the present invention.
[0053] Figure 16 This is a perspective view of a vibrating body with concave and convex shapes along two directions, according to an embodiment of the present invention.
[0054] Figure 17 This is a top view of the aforementioned vibrating body.
[0055] Figure 18 This is a top view of a vibrating body with other structures according to an embodiment of the present invention.
[0056] Figure 19 This is a top view of a vibrating body with other structures according to an embodiment of the present invention.
[0057] Figure 20 This is a graph showing the sound pressure characteristics of the vibrating body of the vibration generating device according to an embodiment of the present invention.
[0058] Figure 21 This is a graph representing the vibration displacement of the aforementioned vibrating body. Detailed Implementation
[0059] The vibration generating apparatus according to an embodiment of the present invention will be described. Furthermore, in the following figures, the X, Y, and Z directions are shown as three mutually orthogonal directions.
[0060] [Structure of the vibration generating device]
[0061] Figure 1 This is a schematic diagram of the vibration generating device 100 according to this embodiment. As shown in the figure, the vibration generating device 100 includes a vibrating body 101, a piezoelectric actuator 102, and a driving device 103. Figure 2 This is a perspective view of the vibration generating device 100. Figure 3 This is a side view of the vibration generating device 100. Furthermore, in Figure 2 and Figure 3 The illustration of the drive unit 103 is omitted.
[0062] The vibrator 101 provides tactile feedback to the user who comes into contact with it. The vibrator 101 can be a plate-shaped component made of glass or resin, such as a liquid crystal panel or the housing of an electronic device. When the vibrator 101 is made of resin, a resin material with a flexural modulus of 3.0 GPa or higher is preferred. The shape and size of the vibrator 101 are not particularly limited. Figure 2 and Figure 3 As shown, one main surface of the vibrator 101 is designated as the first main surface 101a, and the main surface opposite to the first main surface 101a is designated as the second main surface. The irregularities described later are formed on the first main surface 101a.
[0063] A piezoelectric actuator 102 is coupled to the second principal surface 101b of the vibrating body 101 to generate vibration. The piezoelectric actuator 102 has a positive electrode, a negative electrode, and a piezoelectric material layer. When a voltage is applied between the positive and negative electrodes, vibration is generated by deformation of the piezoelectric material layer through the inverse piezoelectric effect. Figure 1 In the figure, positive terminal 102a connected to the positive electrode and negative terminal 102b connected to the negative electrode are represented.
[0064] A positive terminal 102a is connected to a positive wiring 104, and a negative terminal 102b is connected to a negative wiring 105. For example... Figure 1 As shown, the positive terminal wire 104 and the negative terminal wire 105 are connected to the drive device 103. When a drive signal is supplied from the drive device 103, vibration is generated in the piezoelectric actuator 102.
[0065] The piezoelectric actuator 102 can be a component with a laminated structure in which positive and negative electrodes are alternately stacked with piezoelectric material layers, or it can be a component with other structures. The piezoelectric actuator 102 can be formed by bonding it to the second main surface 101b using epoxy resin or the like. Alternatively, two or more piezoelectric actuators 102 can be bonded to the second main surface.
[0066] like Figure 3 As shown, in the vibration generating device 100, the user's finger F contacts the first main surface 101a for use. At this time, by causing the piezoelectric actuator 102, which is coupled to the second main surface 101b, to vibrate, the user's finger F can perceive the touch.
[0067] The driving device 103, for example, is an amplifier, connected to the piezoelectric actuator 102 via positive wiring 104 and negative wiring 105, and supplies a driving signal to the piezoelectric actuator 102. The frequency of the driving signal is not particularly limited, but is preferably 60kHz or higher.
[0068] [About vibrating bodies]
[0069] Regular concave and convex shapes are formed on the first main surface 101a of the vibrating body 101. Figure 4 This is a perspective view of the vibrating body 101, showing the concave-convex shape 101c formed on the first main surface 101a. Furthermore, in Figures 1 to 3 The diagram of the concave-convex 101c is omitted. Figure 5 This is a top view representing the first main plane 101a. Figure 6 This is a cross-sectional view of vibrating body 101. Figure 4 and Figure 5 The cross-sectional view at line AA is shown.
[0070] As shown in these figures, a plurality of recesses 101d and a plurality of protrusions 101e are provided on the first main surface 101a. Each recess 101d extends along a direction parallel to the first main surface 101a (X direction) when viewed from a direction perpendicular to the first main surface 101a (Z direction), and each protrusion 101e extends along the direction in which the recess 101d extends (X direction).
[0071] A plurality of recesses 101d and a plurality of protrusions 101e are alternately provided in the first main surface 101a, forming a concave-convex shape 101c. For example... Figure 6 As shown, the concave-convex portion 101c can be formed such that the cross-sectional shape in the plane (YZ plane) perpendicular to the extension direction of the concave portion 101d and the convex portion 101e becomes a sine wave shape.
[0072] The spacing between the concave portion 101d and the convex portion 101e is equal across the entire concave and convex structure, such as... Figure 6As shown, when the distance between the peaks of the protrusion 101e in the direction perpendicular to the extending direction (X direction) of the concave portion 101d and the convex portion 101e (Y direction) is set as the width W, the width W is preferably 1 mm or more and 10 mm or less. Furthermore, when the height difference between the concave portion 101d and the convex portion 101e in the thickness direction (Z direction) of the vibrator 101 is set as the depth D, the depth D is preferably 0.01 mm or more and 0.1 mm or less. In addition, in Figure 4 and Figure 6 In the illustration, the depth direction (Z direction) of the concave-convex 101c is enlarged by 10 times for easier illustration.
[0073] In this way, by forming a concave-convex surface 101c on the first main surface 101a that is contacted by the user's finger F, it is possible to suppress abnormal noises (contact sounds) generated between the finger F and the first main surface 101a. Figure 7 This is a graph showing the sound pressure characteristics of a vibrating body without any bumps or depressions, for comparison. Figure 8 It is a graph showing the amount of vibration displacement of the vibrator when a finger touches the vibrator.
[0074] like Figure 7 and Figure 8 As shown, when a finger touches a vibrating body, there are vibration peaks at 1 / 2 and 1 / 4 of the input frequency to the piezoelectric actuator. Since the peak at 1 / 4 frequency is in the audible range, it can be heard as a contact sound.
[0075] on the other hand, Figure 9 This is a graph showing the sound pressure characteristics of the vibrating body 100 with the concave and convex surfaces 101c in this embodiment. Figure 10 This is a graph showing the vibration displacement of the vibrating body when finger F contacts it. For example... Figure 9 and Figure 10 As shown, in the vibrator 100, the peak at 1 / 4 frequency can be eliminated, thereby reducing contact noise. This is because the contact between the finger F contacting the first main surface 101a and the first main surface 101a is discontinuous due to the concave-convex shape 101c.
[0076] Furthermore, in the vibrator 101, as described above, the structure of recesses 101d and protrusions 101e arranged at certain intervals allows the irregularities 101c to be formed without sacrificing the light transmittance of the vibrator 101, even when the vibrator 101 is light-transmitting. For example, when the surface of the vibrator is roughened, the vibrator becomes frosted glass-like and it is difficult to maintain light transmittance, while the vibrator 101 can maintain light transmittance.
[0077] Here, as mentioned above, the width W is preferably 1 mm or more and 10 mm or less. This is because when the width W is less than 1 mm, the visual recognition via the vibrator 101 may be reduced, and when it exceeds 10 mm, the protrusions 101c may not be able to contact the finger F. In addition, the depth D is preferably 0.01 mm or more and 0.1 mm or less. This is because when the depth D is less than 0.01 mm, the effect produced by the protrusions 101c cannot be obtained, and when it exceeds 0.1 mm, the tactile sensation will be affected even when not vibrating due to the 101c.
[0078] Furthermore, in the above description, the recess 101d and the convex portion 101e are parallel to the short side direction (X direction) of the vibrating body 101, but are not limited to this. Figure 11 and Figure 12 This is a top view showing other structures of the concave-convex 101c. For example... Figure 11 As shown, the concave portion 101d and the convex portion 101e can also be parallel to the long side direction (Y direction) of the vibrating body 101. Additionally, as... Figure 12 As shown, the concave portion 101d and the convex portion 101e may not be parallel to either the short side direction (X direction) or the long side direction (Y direction) of the vibrating body 101, but extend in the inclined direction.
[0079] Furthermore, the concave-convex 101c is not limited to a cross-sectional shape that becomes a sine wave shape. Figures 13 to 15 This is a cross-sectional view showing other structures of the concave-convex 101c. For example... Figure 13 As shown, the concave-convex portion 101c can be formed such that the cross-sectional shape in the plane (YZ plane) perpendicular to the extension direction of the concave portion 101d and the convex portion 101e becomes a rectangular wave shape.
[0080] In addition, such as Figure 14 As shown, the concave-convex portion 101c can be formed such that the cross-sectional shape in the plane (YZ plane) perpendicular to the extending direction of the concave portion 101d and the convex portion 101e is a triangular wave shape. Furthermore, as... Figure 15 As shown, the concave-convex groove 101c can be formed by a groove extending in one direction. Furthermore, the cross-sectional shape of the groove is not limited to... Figure 15 The triangle shape shown can also be a quadrilateral shape or a semi-circular shape, etc.
[0081] Alternatively, the concave portion 101d and the convex portion 101e of the concave-convex 101c may extend in two directions. Figure 16 This is a perspective view of a vibrating body 101 with concave portion 101d and convex portion 101e extending in two directions. Figure 17 This is a top view representing the first main plane 101a. Figure 16 and Figure 17 The cross-sectional view at the BB line shown is the same as Figure 6 same.
[0082] like Figure 16 and Figure 17 As shown, the first main surface 101a has a plurality of recesses 101d and a plurality of protrusions 101e. When viewed from a direction perpendicular to the first main surface 101a (Z direction), each recess 101d extends along two directions parallel to the first main surface 101a (X direction and Y direction), and each protrusion 101e extends along the direction in which the recess 101d extends (X direction and Y direction).
[0083] In the first main surface 101a, a plurality of recesses 101d and a plurality of protrusions 101e are alternately arranged to form a concave-convex surface 101c. For example... Figure 6 As shown, the concave and convex portions 101c can be formed such that the cross-sectional shape in the planes (YZ plane and XZ plane) perpendicular to the extension directions of the concave portion 101d and the convex portion 101e becomes a sinusoidal shape.
[0084] The spacing between the concave portion 101d and the convex portion 101e is equal across the entire concave and convex structure, such as... Figure 6 As shown, the distance between the peaks of the protrusions 101e in the Y direction, i.e., the width W, is preferably 1 mm or more and 10 mm or less. Furthermore, the distance between the peaks of the protrusions 101e in the X direction, i.e., the width W, is also preferably 1 mm or more and 10 mm or less. This is because when the width W is less than 1 mm, the visual recognition via the vibrator 101 may be reduced, and when it exceeds 10 mm, the finger F may not be able to contact the protrusions 101c.
[0085] Furthermore, the depth D, i.e., the height difference between the recess 101d and the protrusion 101e in the thickness direction (Z direction) of the vibrating body 101, is preferably 0.01 mm or more and 0.1 mm or less. This is because when the depth D is less than 0.01 mm, the effect produced by the recess 101c cannot be obtained, and when it exceeds 0.1 mm, the recess 101c will affect the tactile sensation even when not vibrating. In addition, in Figure 16 In the illustration, the depth direction (Z direction) of the concave-convex 101c is magnified 10 times for clarity.
[0086] In this way, by forming a concave-convex shape 101c with a recess 101d and a convex shape 101e extending in two directions (X direction and Y direction) parallel to the first main surface 101a, it is possible to further suppress the abnormal noise (contact sound) generated between the finger F and the first main surface 101a.
[0087] By providing concave and convex shapes 101c in two directions in the vibrator 101, the peak at 1 / 4 frequency can be eliminated, similar to the case with concave and convex shapes 101c in one direction (see reference). Figure 9 and Figure 10This reduces the contact noise. Furthermore, as described above, the vibrator 101 has a structure in which recesses 101d and protrusions 101e are provided at certain intervals. When the vibrator 101 is light-transmitting, the concave and convex 101c can be formed without losing the light transmittance of the vibrator 101.
[0088] Furthermore, in the above description, the concave portion 101d and the convex portion 101e are parallel to the short side direction (X direction) and the long side direction (Y direction) of the vibrating body 101, but are not limited thereto. Figure 18 and Figure 19 This is a top view showing other structures of the concave-convex 101c. For example... Figure 18 As shown, the concave portion 101d and the convex portion 101e may also extend in an inclined direction, not parallel to the short side direction (X direction) and the long side direction (Y direction) of the vibrating body 101. Additionally, as... Figure 19 As shown, it can also be that the two directions in which the concave portion 101d and the convex portion 101e extend are not orthogonal.
[0089] Furthermore, the cross-sectional shape of the concave-convex 101c is not limited to a sinusoidal shape, such as... Figure 13 and Figure 14 The shape shown can also be a rectangular wave or a triangular wave, and it can also be like... Figure 15 The diagram shows a groove. The cross-sectional shape of the groove is as follows. Figure 15 The shape shown is not limited to a triangle; it can also be a quadrilateral or a semicircle, etc.
[0090] In addition, the vibrator 101 is made of glass or resin material and has unevenness 101c, but is not limited thereto. For example, it may also be a vibrator made of glass or resin material with a flexural modulus of 3.0 GPa or higher, and a film with unevenness 101c is bonded to a substrate with a smooth surface.
[0091] [About drive signals]
[0092] In the vibration generating device 100, the generation of contact sound can also be prevented by using the drive signal supplied to the piezoelectric actuator 102. In the following structure, the first main surface 101a of the vibrating body 101 can be flat, or it can be formed with multiple protrusions and depressions at equal intervals as described above.
[0093] Figure 20 This is a graph showing the sound pressure characteristics of the vibrator 101 when the finger F is not in contact with it and when it is in contact with it. As shown in the graph, when the finger F contacts the vibrator 101, there are peaks at 1 / 2 and 1 / 4 of the frequency of the driving signal, and the peak at the 1 / 4 frequency can be heard as a contact sound.
[0094] Figure 21This is a graph showing the vibration displacement of vibrator 101 when finger F contacts vibrator 101. Similar to the sound pressure characteristics, there are peaks at 1 / 2 and 1 / 4 of the frequency of the driving signal during the vibration of vibrator 101, at which vibrator 101 vibrates when the finger contacts it.
[0095] Here, when the drive device 103 generates a drive signal of 60kHz or higher as described above, the vibration at a 1 / 4 frequency generated in the vibrator 101 is 15kHz or higher. Since vibrations of 15kHz or higher are outside the human audible frequency band, the contact sound will not be heard.
[0096] In this way, in the vibration generating device 100, the driving device 103 supplies driving vibrations of 60 kHz or higher to the piezoelectric actuator, thereby preventing the generation of contact noise and providing the user with tactile feedback.
[0097] The vibration generating device 100 has the structure described above. The vibration generating device 100 can be mounted in various electronic devices such as smartphones or haptic devices.
[0098] Explanation of reference numerals in the attached figures
[0099] 100… Vibration Generating Device
[0100] 101…vibrating body
[0101] 101a…First Main Page
[0102] 101b…Second Main Page
[0103] 101c…concave-convex
[0104] 101d…concave part
[0105] 101e…convex part
[0106] 102…Piezoelectric actuator
[0107] 103… drive unit.
Claims
1. A vibration generating apparatus, characterized by comprising: include: A vibrating body having a first main surface that contacts the user's finger and a second main surface that does not contact the user's finger, the second main surface being disposed on the opposite side of the first main surface; and A piezoelectric actuator coupled to the second main surface, Multiple protrusions and concavities are formed at equal intervals on the first main surface. The second principal surface is a flat surface. The piezoelectric actuator causes the vibrating body to vibrate. The plurality of concave and convex portions have concave and convex portions, and when the vibrating body is not vibrating, there is a height difference between the concave and convex portions.
2. The vibration generating device according to claim 1, characterized in that: The depth of the plurality of protrusions and recesses is greater than 0.01 mm and less than 0.1 mm, and the width is greater than 1 mm and less than 10 mm.
3. The vibration generating device according to claim 1 or 2, characterized in that: The plurality of concave and convex features are alternately formed by a plurality of recesses extending along a first direction parallel to the first main surface and a plurality of protrusions extending along the first direction.
4. The vibration generating device according to claim 3, characterized in that: The plurality of concave and convex shapes are also alternately formed by a plurality of recesses extending along a second direction parallel to the first main surface and different from the first direction, and a plurality of protrusions extending along the second direction.
5. The vibration generating device according to claim 3, characterized in that: The cross-sectional shape of the plurality of concave and convex features in a plane perpendicular to the first direction has a sinusoidal shape.
6. The vibration generating device according to claim 1, characterized in that: The vibrator is made of glass or a resin material with a flexural modulus of 3.0 GPa or higher.
7. The vibration generating device according to claim 1, characterized in that: The vibrator is composed of a substrate and a film adhered to the surface of the substrate. The irregularities are formed on the surface of the membrane.
8. The vibration generating device according to claim 6 or 7, characterized in that: The vibrating body is light-transmitting.
9. The vibration generating device according to claim 1, characterized in that: It also includes a drive device that supplies a drive signal with a frequency of 60 kHz or higher to the piezoelectric actuator.
10. An electronic device, characterized in that: It has a vibration generating device. The vibration generating device includes: a vibrating body having a first main surface that contacts the user's finger and a second main surface that does not contact the user's finger, the second main surface being disposed on the opposite side of the first main surface; and a piezoelectric actuator engaged with the second main surface, wherein a plurality of concave and convex portions are formed at equal intervals on the first main surface, the second main surface being a flat surface, the piezoelectric actuator causing the vibrating body to vibrate, the plurality of concave and convex portions having concave portions and convex portions, and a height difference existing between the concave portions and the convex portions when the vibrating body is not vibrating.
11. A vibration generating apparatus, characterized by comprising: include: A vibrating body having a first principal surface and a second principal surface opposite to the first principal surface; A piezoelectric actuator coupled to the second main surface; as well as The driving device supplies a driving signal with a frequency of 60kHz or higher to the piezoelectric actuator. The sound pressure characteristics of the vibrator show a peak at 1 / 4 of the frequency of the driving signal when a person's finger touches the vibrator, and a peak at a frequency higher than 1 / 4 of the frequency of the driving signal when a person's finger does not touch the vibrator.
12. The vibration generating device according to claim 11, characterized in that: The vibrator is made of glass or a resin material with a flexural modulus of less than 3.0 GPa.
13. An electronic device, characterized in that: It has a vibration generating device. The vibration generating device includes: a vibrating body having a first main surface and a second main surface opposite to the first main surface; a piezoelectric actuator coupled to the second main surface; and a driving device supplying a driving signal with a frequency of 60 kHz or higher to the piezoelectric actuator. The sound pressure characteristics of the vibrator show a peak at 1 / 4 of the frequency of the driving signal when a person's finger touches the vibrator, and a peak at a frequency higher than 1 / 4 of the frequency of the driving signal when a person's finger does not touch the vibrator.