JP2012100042A - Oscillation device and electronic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compact oscillation device capable of reproducing a large volume of sound.SOLUTION: A piezoelectric element 10 is fixed by a first resin member 41 being an elastic member, so that a movable range in vibration is enlarged and also amplitude is enlarged. A second resin member 42 with rigidity lower than that of the first resin member 41 is interposed between the first resin member 41 and a support body 45, so that impedance matching in rigidity is obtained. Consequently, audible sound is reproduced by oscillating an ultrasonic wave restricted to a specified frequency through the use of a high mechanical quality factor Q being the feature of the piezoelectric element 10, so that a large volume of sound is reproduced.

Description

  The present invention relates to an oscillation device provided with a piezoelectric element, and an electronic apparatus having the oscillation device.

  In recent years, demand for portable electronic devices such as mobile phones and notebook computers has been increasing. In such an electronic device, development of a thin portable terminal whose commercial value is an acoustic function such as a videophone, a video playback, and a hands-free phone is being promoted. Under such development, there is an increasing demand for a high-quality sound and a small and thin oscillator device (speaker device) that is an acoustic component.

  Conventionally, an electrodynamic oscillation device has been used as an oscillation device in an electronic device such as a mobile phone. This electrodynamic oscillation device includes a permanent magnet, a voice coil, and a diaphragm. However, there is a limit to reducing the thickness of an electrodynamic oscillator due to its operating principle and structure. On the other hand, Patent Documents 1 and 2 describe using a piezoelectric element as an oscillation device.

  Other examples of the oscillation device using a piezoelectric element include a speaker device, a sound wave sensor that detects a distance to an object using a sound wave oscillated from the piezoelectric element (see Patent Document 3), and the like. Various oscillation devices and electronic devices are known. For example, there is a proposal for realizing a bimorph oscillation device by stacking two piezoelectric elements of the same shape and the same material on an elastic member in two stages (Patent Document 4). There is also a proposal for realizing a bimorph oscillation device by arranging two piezoelectric elements having different planar shapes on both sides of an elastic member (Patent Document 5).

Japanese translation of PCT publication No. 2007-026736 Special table 2007-083497 Japanese Patent Laid-Open No. 03-270282 JP 2002-112391 A JP 2008-28593 A

  An oscillating device using a piezoelectric element generates a vibration amplitude by an electrostrictive action by inputting an electric signal by using a piezoelectric effect of a piezoelectric layer. The electrodynamic oscillation device generates vibration by a piston-type advance / retreat motion, whereas the oscillation device using a piezoelectric element has a bending-type vibration state and thus has a small amplitude. For this reason, it is superior in reducing the thickness of the above-described electrodynamic oscillator.

  However, since the ceramic material is a brittle material and has a small mechanical loss, the mechanical quality factor Q tends to be higher than that of an electrodynamic electroacoustic transducer that generates an amplitude from an organic film. For example, the electrodynamic type has a mechanical quality factor Q of about 3 to 5, while the piezoelectric type has about 50. Since the mechanical quality factor Q indicates sharpness at the time of resonance, the summary means that in the piezoelectric electroacoustic transducer, the sound pressure is high near the fundamental resonance frequency and the sound pressure is attenuated in other bands.

  That is, in the sound pressure level frequency characteristic, there is a problem that the sound characteristic level peaks and valleys occur, and the sound of a specific frequency is emphasized or lost, so that sufficient sound quality for music reproduction or the like cannot be obtained. In addition, there is a problem with respect to the radiation area as well as acoustic characteristics. In piezoelectric electroacoustic transducers, as with electromagnetic transducers, the sound pressure level depends on the volume exclusion amount (the product of the radiation area and amplitude). There is a limit to the reduction of the area, and it does not satisfy a sufficient function as an electroacoustic transducer for a mobile phone. For this reason, an epoch-making technology for producing a small electroacoustic transducer with high sound quality has been required.

  The present invention has been made in view of the above-described problems, and provides an oscillation device capable of reproducing a large volume even with a small size, and an electronic apparatus using the oscillation device.

  The oscillation device of the present invention supports at least a piezoelectric element, a flat piezoelectric element that expands and contracts by application of an electric field, a flat elastic member that constrains one of the two main surfaces of the piezoelectric element, and the piezoelectric element. A first resin member; a second resin member having a smaller longitudinal elastic modulus than the first resin member and supporting the first resin member; and a frame-shaped support member supporting at least the second resin member. .

  A first electronic device of the present invention includes the oscillation device of the present invention and an oscillation drive unit that causes the oscillation device to output an audible sound wave.

  A second electronic device according to the present invention includes an oscillation device according to the present invention, an ultrasonic detection unit that detects an ultrasonic wave oscillated from the oscillation device and reflected by the measurement object, and from the detected ultrasonic wave to the measurement object. And a distance measuring unit for calculating the distance.

  In the oscillation device of the present invention, since the piezoelectric element is fixed by the first resin member that is an elastic member, the movable range during vibration is large and the amplitude is enlarged. In addition, since the second resin member having lower rigidity than the first resin member is interposed between the first resin member and the support, rigidity impedance matching can be achieved. For this reason, audible sound can be reproduced by oscillating an ultrasonic wave limited to a specific frequency using the high mechanical quality factor Q that is a feature of the piezoelectric element, and reproduction at a large volume is possible.

1 is a schematic longitudinal sectional front view showing a structure of an oscillation device according to a first embodiment of the present invention. It is a typical top view which shows the external appearance of an oscillation apparatus. It is a typical longitudinal section front view showing the structure of a piezoelectric element. It is a typical top view which shows the structure of the oscillation apparatus of one modification. It is a schematic diagram which shows operation | movement of the principal part of an oscillation apparatus. It is a schematic diagram which shows operation | movement of an oscillation apparatus. It is a schematic diagram which shows operation | movement of the principal part of an oscillation apparatus. It is a typical longitudinal cross-sectional front view which shows the structure of the oscillation apparatus of 2nd Embodiment of this invention. It is a schematic diagram which shows operation | movement of a bimorph type piezoelectric element. It is a disassembled perspective view which shows the assembly structure of the piezoelectric element of the oscillation apparatus of 3rd Embodiment of this invention. It is a typical top view which shows the structure of the oscillation apparatus of the 4th embodiment of this invention. It is a typical top view which shows the structure of the oscillation apparatus of the 5th embodiment of this invention. It is a vertical front view which shows the structure of the oscillator of one prior art example. It is a typical front view which shows the external appearance of the mobile telephone which is an electronic device.

[First embodiment]
An embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a schematic cross-sectional view showing an electroacoustic transducer of the present embodiment, and FIG. 2 is a schematic top view. As shown in FIG. 1, an oscillation device 50 that is an electrodynamic electroacoustic transducer according to this embodiment includes a plate-like piezoelectric element 10 that expands and contracts by application of an electric field, and one of two main surfaces of the piezoelectric element 10. A flat elastic member 20 that restrains the first resin member 41, a first resin member 41 that supports at least the piezoelectric element 10, and a longitudinal elastic coefficient that is smaller than that of the first resin member 41, and supports at least the first resin member 41. And a frame-like support body 45 supporting at least the second resin member 42.

  More specifically, the lower main surface of the piezoelectric element 10 is restrained by the elastic member 20 to form a vibrator, and both ends thereof are supported by the first resin member 41. A second resin member 42 is interposed between the lower surface of the first resin member 41 and the bottom surface of the support body 45. The piezoelectric element 10 and the elastic member 20 are joined via two first resin members 41 and a second resin member 42 having different elastic moduli. The lead wire 46 is bonded to the end portions of the piezoelectric element 10 and the elastic member 20, and is fixed to the first resin member 41 and the second resin member 42. The terminal 47 is connected.

The piezoelectric element 10 of the present invention has the configuration shown in FIG. 3, and the piezoelectric material 3-b has its upper and lower main surfaces constrained by electrode materials 3-a and 3-c. The piezoelectric material 3-b is not particularly limited as long as it is a material having a piezoelectric effect, but it is not particularly limited, but a material having high electromechanical conversion efficiency, for example, lead zirconate titanate (PZT) or barium titanate. Materials such as (BaTiO ₃ ) can be used. Moreover, although thickness is not specifically limited, It is preferable that they are 10 micrometers-1 mm.

  When a thin film having a thickness of less than 10 μm is used as a ceramic material which is a brittle material, chipping or breakage occurs due to weak mechanical strength during handling, making handling difficult. In addition, when a ceramic having a thickness exceeding 1 mm is used, the conversion efficiency for converting electrical energy into mechanical energy is remarkably reduced, and sufficient performance as the oscillation device 50 cannot be obtained. In general, in a piezoelectric ceramic that generates an electrostrictive effect by inputting an electric signal, the conversion efficiency depends on the electric field strength. Since the electric field strength is expressed by the thickness / input voltage with respect to the polarization direction, an increase in thickness inevitably causes a decrease in conversion efficiency.

  In the piezoelectric element 10 of the present invention, an electrode layer is formed on the main surface in order to generate an electric field. Although the material is not particularly limited, for example, silver or silver / palladium can be used. Silver is used as a general-purpose electrode material with low resistance, which has advantages in manufacturing process and cost. Silver / palladium is a low-resistance material with excellent oxidation resistance, so it has advantages from the viewpoint of reliability. is there.

  Moreover, although the thickness of electrode material is not specifically limited, It is preferable that the thickness is 1-50 micrometers. If the thickness is less than 1 μm, the film thickness is so thin that it cannot be uniformly formed on the electrode, and conversion efficiency may be reduced. Moreover, when the film thickness of the electrode exceeds 100 μm, there is no particular problem in manufacturing, but there is a problem that the electrode layer becomes a constraining surface with respect to the piezoelectric ceramic material and energy conversion efficiency is lowered.

  The piezoelectric element 10 of the present invention has a principal surface on one side constrained by an elastic member 20. The elastic member 20 has a function of propagating vibration generated from the piezoelectric element 10 to the support body 45. At the same time, the elastic member 20 has a function of adjusting the basic resonance frequency of the piezoelectric element 10. The fundamental resonance frequency of the mechanical vibrator depends on the load weight and compliance, as shown by the following formula. In other words, since the compliance is the mechanical rigidity of the vibrator, this means that the fundamental resonance frequency can be controlled by controlling the rigidity of the piezoelectric element 10.

[Equation 1]
f = 1 / (2πL√ (mC))
“M” is mass and “C” is compliance.

  By selecting a material having a high elastic modulus and reducing the thickness of the elastic member 20, the fundamental resonance frequency can be shifted to a low frequency range. The elastic member 20 is not particularly limited as long as it is a material having a high elastic modulus with respect to a ceramic that is a brittle material such as metal or resin, but general-purpose materials such as phosphor bronze and stainless steel are used from the viewpoint of workability and cost. The Moreover, about thickness, it is preferable that it is 5-1000 micrometers. When the thickness is less than 5 μm, there is a problem that mechanical strength is weak, the function as a restraining member is impaired, and the mechanical vibration characteristics of the vibrators vary between manufacturing lots due to a decrease in processing accuracy.

  In addition, when the thickness exceeds 1000 μm, there is a problem in that the restraint on the piezoelectric element 10 due to the increase in rigidity is strengthened and the vibration displacement amount is attenuated. Moreover, it is preferable that the elastic member 20 of this embodiment has a longitudinal elastic modulus, which is an index indicating the rigidity of the material, of 1 to 500 GPa. As described above, when the rigidity of the elastic member 20 is excessively low or excessively high, there is a problem that characteristics and reliability are impaired as a mechanical vibrator.

  In the oscillation device 50 of the present invention, the end portions of the piezoelectric element 10 and the elastic member 20 are joined to the support body 45 via two types of first resin members 41 and second resin members 42. The first resin member 41 is bonded to the piezoelectric material or the elastic member 20 and functions as a mechanism for expanding vibration. In the conventional piezoelectric oscillation device 50, the elastic member 20 that restrains the piezoelectric element 10 is directly bonded to the support body 45. However, in bending vibration, stress concentrates on the support body 45 and the elastic member 20, as shown in FIG. 5, and this structure functions as a fixed end. Therefore, the lower rigidity is displaced from the theory of bending deformation. It is advantageous from the viewpoint of expansion.

  In the present invention, the second resin member 42 is interposed between the first resin member 41 and the bottom of the support body 45. This second resin member 42 is a low-rigidity material compared to the first resin member 41 and has a low elastic modulus, and has a function of expanding vibration displacement and a function of improving drop impact stability. Have. The elastic modulus of the second resin member 42 is preferably 1/10 or less with respect to the elastic modulus of the first resin member 41.

  Moreover, the 2nd resin member 42 and the 1st resin member 41 are joined by the adhesive material, and an epoxy-type adhesive material etc. can be used for the adhesion | attachment. Both the second resin member 42 and the first resin member 41 are preferably materials having high bonding strength with respect to epoxy adhesion. Furthermore, in order to reduce vibration energy loss at the joint, the thickness of the adhesive is preferably 20 μm or less. As shown in FIG. 6, the flexural vibration of the piezoelectric element 10 is converted in the thickness direction of the piezoelectric element 10. That is, an amplitude motion in the thickness direction of the oscillation device 50 is generated, and the driving force and inertia from the piezoelectric element 10 act on the thickness direction as shown in FIG.

  Therefore, it is a feature of the present invention that the amount of deformation is increased by utilizing the restoring force of the second resin member 42 having a high elastic deformation rate. Further, regarding the impact stability at the time of dropping, the energy at the time of impact is absorbed by the second resin member 42, so the reliability is improved. The first resin member 41 and the second resin member 42 are not particularly limited as long as the longitudinal elastic modulus is a polymer material of 100 GPa or less, but from the viewpoint of versatility, polyethylene terephthalate, polyethylene, urethane, Silicon rubber, natural rubber, synthetic rubber, etc. can be used.

  A method for manufacturing the oscillation device 50 of the present invention will be described below. First, the piezoelectric element 10 is a piezoelectric plate having an outer diameter of the piezoelectric material = 5 × 3 mm and a thickness = 200 μm (0.2 mm), and an upper electrode material 3-a and a lower electrode material 3 each having a thickness of 8 μm are formed on both surfaces thereof. -B is formed. The elastic member 20 is phosphor bronze having an outer diameter = 7 × 3 mm and a thickness = 300 μm (0.3 mm). The support 45 is made of SUS304 and is directly bonded to the elastic member 20. The support body 45 is a bathtub-shaped case having an outer diameter = 10 × 5 mm and an inner diameter = 8 × 3.5 mm, and is made of SUS304.

  The piezoelectric material and the elastic member 20 were arranged concentrically at the center. The piezoelectric material was a lead zirconate titanate ceramic, and the electrode layer was a silver / palladium alloy (weight ratio 70%: 30%). The piezoelectric ceramic was manufactured by a green sheet method, fired in the atmosphere at 1100 ° C. for 2 hours, and then subjected to polarization treatment on the piezoelectric material layer. An epoxy adhesive was used for bonding the piezoelectric element 10 and the elastic member 20 to each other. The first resin member 41 is made of polyethylene, and the second resin member 42 is made of natural rubber.

  The operation principle of the oscillation device 50 of the present invention will be described below. The oscillating device 50 of the present invention generates sound waves from a plurality of transducers arranged in parallel toward a radiation surface. Although the frequency is not particularly limited, since the ultrasonic wave oscillated here is used as a carrier for modulated waves, it is preferably outside the audible band, for example, 100 KHz is suitable. In addition, a sound reproduction method using the oscillation device 50 of the present invention will be described.

  In this configuration, the operating principle of a parametric speaker, which is an acoustic regenerator that uses ultrasonic waves as a modulated wave transporter, is used. Here, AM (Amplitude Modulation) modulation, DSB (Double Side Band amplitude modulation) modulation, SSB (Single-Sideband Modulation) modulation, FM (Frequency Modulation) modulated ultrasonic waves are emitted into the air, and the ultrasonic waves Sound reproduction is performed on the principle that audible sound appears due to nonlinear characteristics when propagating in the air.

  Non-linearity includes a phenomenon in which the flow changes from laminar flow to turbulent flow when the Reynolds number indicated by the ratio between the inertial action and viscous action of the flow increases. That is, since the sound wave is slightly disturbed in the fluid, the sound wave propagates nonlinearly. However, the amplitude of the sound wave in the low frequency band is non-linear, but the amplitude difference is very small, and is usually handled as a phenomenon of linear theory.

  On the other hand, nonlinearity can be easily observed with ultrasonic waves, and when radiated into the air, harmonics with nonlinearity are remarkably generated. In general, when sound waves are in a dense state where molecular groups are mixed in the air in the air, and it takes time for the air molecules to recover rather than compress, the air that cannot be recovered after compression is continuously propagated air. This is the principle that an audible sound is generated by colliding with a molecule and generating a shock wave.

  As described above, the oscillation device 50 according to the present invention is highly reliable, and can be reproduced in a small size and a large volume. Further, since ultrasonic waves are used, directivity is narrow, and industrial value is great in terms of protecting user privacy.

  In summary, the oscillation device 50 of the present invention can also be used as a sound source of an electronic device (for example, a mobile phone, a laptop personal computer, a small game device, etc.). Since the entire oscillation device 50 is not increased in size and the acoustic characteristics are improved, it can be suitably used for a portable electronic device.

  In the above embodiment, the oscillating device 50 in which the piezoelectric element 10, the elastic member 20, and the support body 45 are planar and rectangular is illustrated. However, as shown in FIG. 4, an oscillation device in which the piezoelectric element 10, the elastic member 20, and the support body 45 are circular can also be implemented.

[Second embodiment]
A second embodiment of the present invention will be described with reference to FIG. The present embodiment is characterized in that the elastic member 20 is constrained by two piezoelectric elements 10a and 10b with respect to the first embodiment. That is, it is a bimorph structure using two piezoelectric elements 10a and 10b. As shown in FIG. 9, the bimorph type piezoelectric elements 10a and 10b are formed by bonding two piezoelectric ceramics whose polarization directions are reversed and bending them by extending one in the longitudinal direction and shrinking the other. Compared to a unimorph structure composed of a single piezoelectric element 10a, 10b in the first form, a larger displacement can be obtained. For the two piezoelectric elements 10a and 10b, the same piezoelectric material as in the first embodiment can be used. Further, the two piezoelectric elements 10a and 10b may have the same shape or different shapes.

  As described above, the oscillation device according to the present embodiment can be used as a sound source of an electronic device (for example, a mobile phone, a laptop personal computer, a small game device, or the like). Since the entire oscillation device is not increased in size and the acoustic characteristics are improved, it can be suitably used for portable electronic devices.

[Third embodiment]
A third embodiment of the present invention will be described with reference to FIG. In this embodiment, it is composed of a multilayer piezoelectric element. As shown in FIG. 10, the piezoelectric element 12 has a multilayer structure in which piezoelectric plates 13a to 13e made of a piezoelectric material are laminated in five layers. Between the piezoelectric plates, electrode layers (conductor layers) 14a to 14d are formed one by one. The polarization directions of the piezoelectric plates 13a to 13e are opposite to each other, and the direction of the electric field is also alternately opposite. According to the piezoelectric element 12 having such a laminated structure, since the electric field strength generated between the electrode layers 14a to 14d is high, the driving force of the piezoelectric element as a whole is improved by an amount corresponding to the number of laminated piezoelectric plates 13a to 13e. To do.

  As described above, the oscillation device according to the present embodiment can also be used as a sound source of an electronic device (for example, a mobile phone, a laptop personal computer, a small game device, etc.). Since the entire oscillation device is not increased in size and the acoustic characteristics are improved, it can be suitably used for portable electronic devices.

[Fourth embodiment]
A fourth embodiment of the present invention will be described with reference to FIG. In the present embodiment, the shape of the piezoelectric element 10 is changed with respect to the first embodiment. By changing the shape of the piezoelectric element 10 in this way, any material for which a mass production process has been established can be used, and the degree of freedom in design is improved. Regarding the shape, any shape material such as a rectangle, an ellipse, and a circle can be used.

  As described above, the oscillation device according to the present embodiment can be used as a sound source of an electronic device (for example, a mobile phone, a laptop personal computer, a small game device, or the like). Since the entire oscillation device is not increased in size and the acoustic characteristics are improved, it can be suitably used for portable electronic devices.

[Fifth embodiment]
A fifth embodiment of the present invention will be described with reference to FIG. In the present embodiment, the shape and number of the piezoelectric elements 10 are changed with respect to the first embodiment. In this configuration, two small piezoelectric elements 10 are used. By changing the number and shape of the piezoelectric elements 10 in this way, any material for which a mass production process has been established can be used as in the fourth embodiment, and the degree of freedom in design is improved.

  As described above, the oscillation device according to the present embodiment can be used as a sound source of an electronic device (for example, a mobile phone, a laptop personal computer, a small game device, or the like). Since the entire oscillation device is not increased in size and the acoustic characteristics are improved, it can be suitably used for portable electronic devices.

[Other embodiments of the invention]
The characteristic evaluation of the oscillation device of the present invention was performed using evaluation items 1 to 2 below.

  (Evaluation 1) Measurement of sound pressure level frequency characteristics: The sound pressure level when an AC voltage of 1 V was input was measured with a microphone placed at a position away from the piezoelectric element by a predetermined distance. The predetermined distance is 10 cm unless otherwise specified, and the frequency measurement range is 10 Hz to 10 kHz.

  (Evaluation 2) Drop impact test: A mobile phone equipped with an oscillation device was naturally dropped 5 times from directly above 50 cm, and a drop impact stability test was performed. Specifically, breakage such as cracks after the drop impact test was visually confirmed, and the sound pressure characteristics after the test were further measured. As a result, the difference in sound pressure level (referring to the difference between the sound pressure level before the test and the sound pressure level after the test) was 3 dB or less, and 3 dB or more was evaluated as x.

[Example 1]
The characteristics of the oscillation device described in the first embodiment of the present invention were evaluated.
[Comparative Example 1]
As Comparative Example 1, the conventional electrodynamic oscillation device of FIG.
[Example 2]
As Example 2, the oscillation device of the second embodiment was created.
[Example 3]
As Example 3, the oscillation device of the third embodiment was created.
[Example 4]
As Example 4, the oscillation device according to the fourth embodiment was produced.
[Example 5]
As Example 5, the oscillation device according to the fifth embodiment was produced.

上記の結果より明らかのように、実施例１〜５の発振装置によれば、小型でかつ高い音圧レベルを有し、音圧レベル周波数特性は平坦である。

As is clear from the above results, according to the oscillation devices of Examples 1 to 5, it is small and has a high sound pressure level, and the sound pressure level frequency characteristic is flat.

[Example 6]
As Example 6, a mobile phone as shown in FIG. 14 was prepared, and the oscillation device of Example 1 was mounted in the casing. Specifically, the oscillation device is attached to the inner side surface of the casing of the mobile phone.
[Example 7]
As Example 7, a mobile phone as shown in FIG. 14 was prepared, and the oscillation device of Example 2 was mounted in the casing. Specifically, the oscillation device is attached to the inner side surface of the casing of the mobile phone.
[Example 8]
As Example 8, a mobile phone as shown in FIG. 14 was prepared, and the oscillation device of Example 3 was mounted in the casing. Specifically, the oscillation device is attached to the inner side surface of the casing of the mobile phone.
[Example 9]
As Example 9, a mobile phone as shown in FIG. 14 was prepared, and the oscillation device of Example 4 was mounted in the casing. Specifically, the oscillation device is attached to the inner side surface of the casing of the mobile phone.
[Example 10]
As Example 10, a mobile phone as shown in FIG. 14 was prepared, and the oscillation device of Example 5 was mounted in the casing. Specifically, the oscillation device is attached to the inner side surface of the casing of the mobile phone.

上記の結果より明らかのように、実施例６〜１０の発振装置によれば、小型でかつ高い音圧レベルを有することが確認された。

As is clear from the above results, it was confirmed that the oscillators of Examples 6 to 10 were small and had a high sound pressure level.

  The present invention is not limited to the present embodiment, and various modifications are allowed without departing from the scope of the present invention. For example, in the above embodiment, the use of the oscillation device 50 as a sound generator for a mobile phone has been exemplified. However, the oscillation device 50, an ultrasonic detection unit that detects ultrasonic waves that are oscillated from the oscillation device 50 and reflected by the measurement object, and a distance measurement unit that calculates a distance from the detected ultrasonic wave to the measurement object It is also possible to implement an electronic device (not shown) having.

3-a Electrode material 3-b Piezoelectric material 3-c Elastic material 10 Piezoelectric element 12 Piezoelectric element 20 Elastic member 41 First resin member 42 Second resin member 45 Support body 46 Lead wire 47 Terminal 50 Oscillator

Claims (10)

A plate-like piezoelectric element that expands and contracts by application of an electric field;
A plate-like elastic member that restrains one of the two main surfaces of the piezoelectric element;
A first resin member supporting at least the piezoelectric element;
A second resin member supporting at least the first resin member having a smaller longitudinal elastic modulus than the first resin member;
A frame-like support body supporting at least the second resin member;
An oscillation device having   The oscillation device according to claim 1, wherein a longitudinal elastic modulus of the first resin member and the second resin member is 100 GPa or less. The first resin member is directly bonded to the piezoelectric material and the elastic member;
The oscillation device according to claim 1, wherein the second resin member is interposed between the support and the first resin member.   The oscillation device according to any one of claims 1 to 3, wherein an oscillation frequency of the piezoelectric element is 20 kHz or more.   The oscillation device according to any one of claims 1 to 4, wherein a planar shape of a main surface of the piezoelectric element is a rectangle.   The oscillation device according to any one of claims 1 to 4, wherein a planar shape of a main surface of the piezoelectric element is circular.   The oscillation device according to any one of claims 1 to 6, wherein the piezoelectric element has a laminated structure in which ceramic layers and electrode layers are alternately laminated.   The oscillation device according to any one of claims 1 to 7, wherein the piezoelectric element oscillates an ultrasonically modulated ultrasonic wave. An oscillation device according to any one of claims 1 to 8,
An oscillation drive unit for outputting an audible sound wave to the oscillation device;
Electronic equipment having An oscillation device according to any one of claims 1 to 8,
An ultrasonic detector for detecting ultrasonic waves oscillated from the oscillation device and reflected by the measurement object;
A distance measuring unit for calculating a distance from the detected ultrasonic wave to the measurement object;
Electronic equipment having

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