JP2018067704A - Vibrator, ultrasonic motor, and optical equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem in which, when performing ultrasonic flaw detection evaluation as a product evaluation after bonding a piezoelectric element and a diaphragm, a white part due to peeling of adhesion occurs in part.SOLUTION: A vibrator 5 has an adhesive layer 1 between a piezoelectric element 7 made of piezoelectric ceramics having an electrode 6 and a diaphragm 3. The adhesive layer 1 contains organic particles 4 having an average particle diameter taken by the number of particles of 5 μm or more and 15 μm or less in a resin 8 in an amount of 50 parts by mass or more and 80 parts by mass or less per 100 parts by mass of the resin.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an adhesion technique in an ultrasonic motor in which a vibrator and a friction member move relative to each other, and more particularly, to an improvement in adhesion between a piezoelectric element constituting a vibrator and a vibration plate in the ultrasonic motor.

Conventionally, a piezoelectric element made of a piezoelectric ceramic such as lead zirconate titanate (PZT) having electrodes such as silver and copper, a vibrator in which a vibration plate is fixed with an adhesive, and a moving body are brought into frictional contact and moved. Sonic motors are known. Various proposals (for example, Patent Document 1) relating to an imaging apparatus including the ultrasonic motor as a camera mechanism or a lens drive source have been made.
In the vibrator bonding step, the thickness of the adhesive layer between the piezoelectric element and the vibration plate becomes a constant film thickness by controlling the amount of adhesive to be applied and the force for pressing the piezoelectric element and the vibration plate. Was managed as such.
However, the piezoelectric element varies in the amount of warp generated when the polarization treatment is performed and the surface roughness of electrodes such as silver and copper. Therefore, in the conventional bonding process, the thickness of the adhesive layer varies greatly even when the amount of adhesive applied and the pressure applied are controlled due to variations in warpage and surface roughness of the piezoelectric elements before bonding.
In order to control the thickness of the adhesive layer, in Patent Document 2, an adhesive in which fine particles such as silica (elastic modulus: 80 GPa) having a particle diameter of 1 μm to 5 μm are mixed with an electromechanical conversion element such as a piezoelectric element and a fixed body. It is described that the thickness of the adhesive layer is managed by using the adhesive layer.

JP2015-126692A Patent 5028905

When the technique of Patent Document 2 is applied to the ultrasonic motor described in Patent Document 1, an adhesive containing silica fine particles of 1 μm or more and 5 μm or less is bonded between a piezoelectric element made of piezoelectric ceramics having an electrode layer and a diaphragm. It is applied in the middle, and after application, it is cured by heating in a pressurized state. Then, after heat curing, an ultrasonic flaw detection inspection is performed as one item of quality confirmation of the bonded vibrator.
Here, when the pressure is increased in order to reduce the thickness of the adhesive layer, in some vibrators, there is a problem in quality such as defective adhesion due to peeling of the piezoelectric element and the diaphragm.
In addition, the piezoelectric element is subjected to polarization treatment before bonding. Therefore, when the piezoelectric element warped about 20 μm and the diaphragm are pressure-bonded, the electrode layer of the piezoelectric element is cracked by the silica fine particles in the adhesive, and partly peels off from the adhesive interface due to the peeling of the piezoelectric element and the electrode layer. There is also a new problem of doing. A partly peeled portion of the bonded portion is an abnormal portion that occurs in the ultrasonic inspection.
The present invention has been made in consideration of the above-described problems, and an object thereof is to reduce peeling that occurs in part when the bonded diaphragm is subjected to ultrasonic flaw detection.

In the present invention, in order to reduce the peeling of the bonded portion that occurs after the bonding assembly, which is the above problem, the bonding between the piezoelectric element and the diaphragm is improved.
That is, the present invention is a vibrator having an adhesive layer between a piezoelectric element made of piezoelectric ceramic provided with an electrode and a diaphragm, wherein the adhesive layer has a number average particle diameter of 5 μm to 15 μm on a resin. The following organic particles are contained in an amount of 50 to 80 parts by mass per 100 parts by mass of the resin.
The present invention also relates to an ultrasonic motor that moves by bringing the vibrator and the moving body into frictional contact, and the present invention further includes an optical device having an optical member that is mechanically connected to the ultrasonic motor. About.

  According to the present invention, the above-mentioned crack of the electrode layer is eliminated by the adhesive layer containing specific organic particles, and it is possible to reduce the interfacial peeling after the bonding assembly of the vibrator using the piezoelectric element having warpage.

It is the schematic which shows the state before pressure-bonding the piezoelectric element and diaphragm which comprise the vibrator | oscillator of this invention. It is the schematic which shows one embodiment of the vibrator | oscillator of this invention. It is the schematic which shows the vibrator | oscillator of this invention which pressure-bonded the piezoelectric element and the diaphragm. It is the schematic which shows one embodiment of the piezoelectric element which comprises the vibrator | oscillator of this invention. It is the schematic which showed the manufacturing process of the vibrator | oscillator of this invention. It is the schematic which shows one embodiment of the ultrasonic motor of this invention. It is the schematic which shows one embodiment of the optical instrument of this invention.

  Hereinafter, specific embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 shows that a piezoelectric element 7 and a diaphragm 3 made of a piezoelectric ceramic 2 having an electrode layer 6 such as silver or copper in a warped state are applied with an adhesive 9 containing organic particles 4. The state before pressure bonding is shown. As will be described later, this warping is caused by internal strain occurring in the piezoelectric ceramic because it is polarized so that the polarization direction is aligned in one direction.

  FIG. 2 is a schematic view showing an embodiment of the vibrator of the present invention, and FIG. 3 is a cross-sectional view in the AA direction of FIG. The vibrator of the present invention has an adhesive layer 1 between the piezoelectric element 7 and the diaphragm 3 as shown in FIG. Here, FIG. 2 shows an embodiment in which the diaphragm has a protrusion 10.

  As shown in FIG. 3, the vibrator of the present invention has an adhesive layer 1 between a piezoelectric element 7 made of piezoelectric ceramics 2 having an electrode 6 and a diaphragm 3. The adhesive layer 1 is composed of a resin 8 in which an adhesive is solidified and organic particles 4 characterized by the present invention. This is a state after an adhesive is applied between the piezoelectric element 7 and the diaphragm 3 and pressure-bonded.

  Here, examples of the piezoelectric ceramic used in the vibrator of the present invention include lead-containing piezoelectric materials such as PZT (lead zirconate titanate). This is because the loss of the ultrasonic motor caused by the piezoelectric element can be reduced because it has a high piezoelectric constant.

  Further, lead-free piezoelectric materials such as barium calcium zirconate titanate, sodium potassium niobate, bismuth ferrite, sodium niobate, bismuth titanate, and bismuth sodium titanate can be used. It is because it is excellent in environmental resistance.

  Further, in this specification, ceramics is a bulk sintered body having a uniform composition obtained by firing a raw material powder containing a metal element, and has a thickness of 0.2 mm or more. The thickness is preferably 1.0 mm or less from the viewpoint of easy polarization treatment. Even when a lead-free piezoelectric material is used, ceramics that contain lead are not excluded.

  FIG. 4 is a schematic view showing an embodiment of the piezoelectric element 7 constituting the vibrator of the present invention, and the piezoelectric element 7 is composed of a piezoelectric ceramic 2 having electrodes. In the piezoelectric element 7, electrodes 6, 61, 62 and 63 are attached to opposing surfaces of the piezoelectric ceramic 2 having a rectangular parallelepiped shape. On one side, an electrode pattern as shown in FIG. 4A is formed, and + in the figure indicates the polarization direction. It shows that the polarization treatment is performed through the electrodes 61 and 62 so that the polarization direction is the same as the thickness direction of the piezoelectric ceramic 2. The other surface is a surface to be bonded to the diaphragm having the electrode 6 attached to almost the entire surface as shown in FIG. Here, the electrode 63 is electrically connected to the electrode 6 on a surface orthogonal to the opposed surface (not shown). Further, the vibrator of the present invention is set so as to resonate in each of the X direction (longitudinal direction) and the Y direction (short direction) of FIG. 2 when a high frequency voltage is applied. As a result of performing an ultrasonic flaw detection test after bonding assembly on the vibrator 5 bonded with the adhesive containing the organic particles 4 in FIG. 3, the interfacial peeling at the bonded portion that had occurred so far was reduced.

  From the above, it is possible to provide a vibrator in which peeling of the bonded portion, which has occurred after the bonding assembly of some vibrators, is improved.

  If the adhesive layer is thick, the adhesive surface is less likely to be peeled off, but the vibration loss increases due to the elasticity of the adhesive layer, resulting in a loss of impedance characteristics, which is a basic characteristic of the ultrasonic motor.

  Next, each component contained in the adhesive layer 1 of the vibrator of the present invention will be described.

  The adhesive layer 1 of the vibrator of the present invention is composed of a resin 8 and organic particles 4 characterized by the present invention. As the resin, a thermosetting adhesive selected from an epoxy resin, an acrylic resin, and an alkyd resin can be appropriately selected and used as a resin precursor.

  Examples of the organic particles 4 contained in the adhesive layer 1 of the vibrator of the present invention include thermosetting resins such as epoxy resins, acrylic resins, phenol resins, urethane resins, unsaturated polyesters, polyimides, polycarbonates, nylons, polyacetals. , Thermoplastic resins such as polyethylene terephthalate, polysulfone, polyarylate, polyetherimide, polyetheretherketone, polyphenylene sulfide, polyamideimide, and liquid crystal polymer can be used.

  The organic particles 4 need to be contained in an amount of 50 to 80 parts by mass, preferably 60 to 70 parts by mass, per 100 parts by mass of the resin. When the added content of the organic particles 4 is less than 50 parts by mass, the organic particles are buried in the deficient portions of the electrode layer 6 of the piezoelectric element 7 and the effect as a spacer of the adhesive layer is lost. Moreover, since it will reduce an adhesive component when it exceeds 80 mass parts, it will become easy to peel.

  The particle diameter of the organic particles 4 is required to be 5 to 15 μm, preferably 10 to 15 μm in terms of number average particle diameter. When the particle diameter of the organic particles 4 is less than 5 μm, the organic particles 4 are buried in the surface roughness (usually Ra: 3 μm) of the electrode 6 of the piezoelectric element 7 and the effect as a spacer is lost. On the other hand, if the particle diameter exceeds 15 μm, the adhesive layer must be thick, and the vibration characteristics of the ultrasonic motor are abruptly deteriorated.

  The organic particles 4 are preferably round particles or spherical particles, but need not be true spheres.

  The elastic modulus of the organic particles 4 is preferably 0.48 GPa or more and 10.0 GPa or less, and more preferably 1.5 GPa or more and 4.0 GPa or less. If the elastic modulus of the organic particles 4 is less than 0.48 GPa, the organic particles may be crushed when pressure bonded, and the spacer effect may be lost. Also, if the elastic modulus exceeds 10.0 GPa, the electrode layer 6 of the piezoelectric element 7 cracks when it is pressure-bonded, and it becomes easy to peel off during a high temperature / high humidity test, so that it may not be usable. .

  The elastic modulus was measured by preparing a cylindrical test piece having a size defined in JIS K 7208 “Plastic Compression Test Method”.

[Method for Preparing Adhesive Composition]
Specific examples will be described later, but an adhesive composition containing organic particles 4 can be obtained by mixing and dispersing a predetermined amount of adhesive and organic particles using a known mixing / dispersing apparatus. .

[Method of bonding piezoelectric element and diaphragm]
Using the prepared adhesive composition, the process proceeds to the next bonding step. As a specific method for applying the adhesive composition, the adhesive composition is put into a 5 cm ³ syringe of a dispenser application device and applied to the surface of the diaphragm 3 in a certain amount (FIG. 5A).

  The diaphragm 3 coated with the adhesive composition is bonded to the polarization-treated piezoelectric element 7 warped by about 20 μm with a pressure of 0.45 MPa (FIG. 5B).

  In a state where the diaphragm 3 and the piezoelectric element 7 are pressurized, they are put into a constant temperature dryer and the adhesive is cured to obtain the bonded state of the present invention (FIG. 5C).

  Thus, although the film thickness of the adhesive layer obtained by adhering the adhesive is affected by the size of the organic particles 4, it is preferably 4.1 μm or more and 14.8 μm or less, and is 4.1 μm or more and 10.0 μm or less. Is more preferable.

[Evaluation of ultrasonic flaw detection after bonding]
For ultrasonic flaw detection after bonding, the vibrator 5 bonded with the diaphragm 3 and the piezoelectric element 7 is placed in a water tank for ultrasonic flaw detection evaluation, and the peeling of the bonding interface is detected based on the presence or absence or strength of the reflected wave of ultrasonic waves. It was. In the ultrasonic image of the vibrator 5 obtained by the ultrasonic flaw detection evaluation, the peeled portion of the adhesion interface appeared as a white portion, and the ratio of the white portion of the adhesion portion was quantified. The vibrator 5 in which the white portion was generated was defined as NG.

[Measurement of average thickness of adhesive layer]
The average thickness of the adhesive layer was measured by cutting a cross section in the longitudinal direction of the vibrator in which the vibration plate 3 and the piezoelectric element 7 were bonded, and observing the thickness of the adhesive layer with an electron microscope (SEM). The average thickness of the adhesive layer was determined by calculating the area of the adhesive layer by image processing and dividing by the length in the longitudinal direction.

[Ultrasonic motor]
The ultrasonic motor of the present invention is characterized in that it moves by bringing the vibrator of the present invention and a moving body into frictional contact. FIG. 6 is a schematic view showing an embodiment of the ultrasonic motor of the present invention. In FIG. 6, the moving body 28 is in pressure contact with the vibrator 5 via the protrusion 10 of the vibrator. When a voltage is applied to the vibrator 5 through the power supply member 27 (see FIG. 7) by a voltage input means (not shown), a traveling wave is generated in the diaphragm 3. Two traveling waves are generated, and one is a traveling wave having three nodal lines parallel to the Y direction by secondary out-of-plane vibration in the X direction in FIG. The other is primary out-of-plane vibration in the Y direction, which is a traveling wave having two nodal lines parallel to the X direction. These two traveling waves cause an elliptical motion at the protrusion of the vibrator.

[Evaluation of dynamic characteristics of ultrasonic motor]
The transducer 5 obtained by the present invention was evaluated for impedance, which is a basic characteristic of the ultrasonic motor. It was evaluated whether there was a large difference in the frequency at which the moving speed of the motor reached 100 mm / sec. The vibrator 5 whose frequency is shifted from the product standard or whose moving speed is lower is NG.

[Optical equipment]
The optical apparatus of the present invention includes the optical member that is mechanically connected to the ultrasonic motor of the present invention.

  FIG. 7 is a schematic view showing an embodiment of the optical apparatus (focus lens portion of the lens barrel device) of the present invention. The optical apparatus of the present invention includes the optical member that is mechanically connected to the ultrasonic motor of the present invention. As shown in FIG. 7, in the focus lens portion of the lens barrel device, the ultrasonic motor and the lens that is an optical member are mechanically connected by a lens holding member 15 or the like.

  Specifically, the vibrator 5 is fixed to the holding member 11 by welding or the like, and is configured not to generate unnecessary vibration. The holding member 11 is fixed to the movable housing 12 with screws 13 and is integrated with the vibrator 5.

  By attaching the two guide members 14 to the movable housing 12, the ultrasonic motor can move straight on the guide member 14. The lens 16 is fixed to the lens holding member 15 and has an optical axis (not shown) parallel to the moving direction of the ultrasonic motor. Similarly to the ultrasonic motor, the lens holding member 15 moves in a straight line on the two guide members 14 to perform focal position alignment. The two guide members 14 are members that allow the movable housing 12 and the lens holding member 15 to be fitted together so that the movable housing 12 and the lens holding member 15 can move straightly. With such a configuration, the movable housing 12 and the lens holding member 15 can move straight on the guide member 14.

  The connecting member 17 is a member that transmits the driving force generated by the ultrasonic motor to the lens holding member 15, and is fitted and attached to the lens holding member 15. As a result, the lens holding member 15 can move smoothly in both directions along the two guide members 14 together with the movable housing 12.

  The sensor 18 detects the position of the lens holding member 15 on the guide member 14 by reading position information of the scale 19 attached to the side surface portion of the lens holding member 15. It is provided to calculate the speed of the ultrasonic motor from the detected value and feed back the speed data to the control unit when not shown.

  In the above, a lens barrel device for a single-lens reflex camera has been described as an optical device. However, an ultrasonic motor is provided regardless of the type of camera, such as a compact camera in which a lens and a camera body are integrated, or an electronic still camera. It can be applied to various optical instruments.

  Next, the effects of the present invention will be specifically described with reference to examples and comparative examples.

[Example 1]
Add 70% by mass of acrylic particles of organic particles (number average particle size 5 μm):
First, as in the composition shown in Table 1, 50 g of a two-component heat-cured epoxy adhesive (product name: manufactured by Epoxy Technology Co., Ltd.), which is a resin precursor, is used as an organic particle 4 having a number average particle size of 5 μm. 35 g of acrylic particles (manufactured by Sekisui Chemical Co., Ltd.) having a rate of 0.48 GPa are weighed (70 parts by mass of organic particles per 100 parts by mass of the adhesive; 70% by mass added).

  These weighed adhesive and organic particles are dispersed in a 250 ml dedicated container of a planetary rotor type mixing / dispersing device (trade name: manufactured by Kentaro Awatori / Sinky). Mixing and dispersing time is 5 minutes.

  Using the prepared adhesive composition, the process proceeds to the next bonding step.

The adhesive composition is placed in a 5 cm ³ syringe of a dispenser coating device, and a predetermined amount is applied to the surface of the diaphragm 3, and the diaphragm 3 coated with the adhesive composition is bonded to the piezoelectric element 7 (silver electrode 6 (elastic modulus: Bonding is performed with PZT (longitudinal direction: 8.9 mm, short side direction: 5.7 mm, thickness: 0.4 mm) having a pressure of 0.45 MPa having a pressure of 10 GPa and a thickness of 2 μm.

  In a state where the diaphragm 3 and the piezoelectric element 7 are pressurized, they are placed in a constant temperature dryer, and the adhesive of the adhesive composition is cured to form an adhesive layer to obtain the vibrator of the present invention. The curing time is 55 minutes at 120 ° C. Moreover, the average film thickness of the adhesive layer of this example was 4.1 μm.

  After bonding the diaphragm 3 and the piezoelectric element 7 with the adhesive of the adhesive composition, ultrasonic flaw detection evaluation was performed. As a result, a white portion indicating peeling of the bonded portion was not recognized in the ultrasonic image, and the bonding was good.

  Next, as a result of evaluating the impedance characteristics of the ultrasonic motor, good characteristics exceeding the standard were obtained. The obtained results are shown in Table 2.

[Example 2]
Add 70% by mass of acrylic particles of organic particles (number average particle size 15 μm):
The adhesive composition of Example 1 is the same as that of Example 1 except that the acrylic particles as the organic particles 4 have a number average particle diameter of 15 μm. Moreover, the average film thickness of the adhesive layer of this example was 14.2 μm.

  After the vibration plate 3 and the piezoelectric element 7 were bonded with the adhesive of the obtained adhesive composition, ultrasonic flaw detection evaluation was performed. As a result, a white portion indicating peeling of the bonded portion was not recognized in the ultrasonic image, and the bonding was good.

  Next, as a result of evaluating the impedance characteristics of the ultrasonic motor, good characteristics exceeding the standard were obtained. The obtained results are shown in Table 2.

Example 3
Add 50% by mass of epoxy resin of organic particles (number average particle size 10 μm):
As the organic particles 4, an epoxy resin having an elastic modulus of 4.0 GPa, an average number particle size of 10 μm, and an addition amount of 50% by mass was used. The average film thickness of the adhesive layer in this example was 9.9 μm.

  After the vibration plate 3 and the piezoelectric element 7 were bonded with the adhesive of the obtained adhesive composition, ultrasonic flaw detection evaluation was performed. As a result, a white portion indicating peeling of the bonded portion was not recognized in the ultrasonic image, and the bonding was good.

  Next, as a result of evaluating the impedance characteristics of the ultrasonic motor, good characteristics exceeding the standard were obtained. The obtained results are shown in Table 2.

Example 4
Add 80% by mass of epoxy resin with organic particles (number average particle size 15 μm):
The organic particles 4 are the same as the adhesive composition of Example 3 except that the number average particle diameter is 15 μm and the addition amount is 80% by mass. The average film thickness of the adhesive layer in this example was 14.8 μm.

  After the vibration plate 3 and the piezoelectric element 7 were bonded with the adhesive of the obtained adhesive composition, ultrasonic flaw detection evaluation was performed. As a result, a white portion indicating peeling of the bonded portion was not recognized in the ultrasonic image, and the bonding was good.

  Next, as a result of evaluating the impedance characteristics of the ultrasonic motor, good characteristics exceeding the standard were obtained. The obtained results are shown in Table 2.

Example 5
As piezoelectric ceramic 2, barium calcium zirconate titanate is used, and 70% by mass of organic particles (number average particle size 5 μm) acrylic particles are added:
As the adhesive, an epoxy / thiol one-component heat-cured epoxy adhesive (manufactured by Kyoritsu Chemical Industry) that initiates the curing reaction within 80 ° C. was used. The mixing and dispersing step and the bonding step of the organic particles 4 are the same as in Example 1.

  In a state where the diaphragm 3 and the piezoelectric ceramic 2 were pressurized, they were put in a constant temperature dryer and the adhesive of the adhesive composition was cured to obtain the vibrator of the present invention. The curing time is 30 minutes at 80 ° C.

  After the vibration plate 3 and the piezoelectric element 7 were bonded with the adhesive of the obtained adhesive composition, ultrasonic flaw detection evaluation was performed. As a result, a white portion indicating peeling of the bonded portion was not recognized in the ultrasonic image, and the bonding was good.

  Next, as a result of evaluating the impedance characteristics of the ultrasonic motor, good characteristics exceeding the standard were obtained. The obtained results are shown in Table 2.

[Comparative Example 1]
When organic particles are not added:
The adhesive composition is the same as that of Example 1 except that the organic particles 4 are not added. Table 1 shows the composition. The average film thickness of the adhesive layer in this example was 1.3 μm.

  After the vibration plate 3 and the piezoelectric element 7 were bonded with the obtained adhesive, ultrasonic flaw detection evaluation was performed. As a result, 40% of a white portion showing partial peeling of the bonded portion was recognized in the ultrasonic image, and the result was NG.

[Comparative Example 2]
Add 70% by mass of acrylic resin with organic particles (number average particle size 3 μm):
The organic particles 4 are the same as the adhesive composition of Example 1 except that the number average particle diameter is 3 μm. The average film thickness of the adhesive layer in this example was 1.8 μm.

  After the vibration plate 3 and the piezoelectric element 7 were bonded with the adhesive of the obtained adhesive composition, ultrasonic flaw detection evaluation was performed. As a result, 35% of a white portion showing partial peeling of the bonded portion was recognized in the ultrasonic image, which was NG.

[Comparative Example 3]
Add 90% by mass of acrylic resin of organic particles (number average particle size 10 μm):
The organic particles 4 are the same as in Example 1 except that the number average particle diameter is 10 μm and the addition amount is 90% by mass. The average film thickness of the adhesive layer in this example was 9.2 μm.

  After the vibration plate 3 and the piezoelectric element 7 were bonded with the adhesive of the obtained adhesive composition, ultrasonic flaw detection evaluation was performed. As a result, 17% of the white part showing partial peeling of the adhesive part was recognized in the ultrasonic image, which was NG.

  Next, as a result of evaluating the impedance characteristics of the ultrasonic motor, the moving speed of the ultrasonic motor was less than 100 mm / sec, which was NG. The obtained results are shown in Table 2.

  The ultrasonic motor of the present invention can be suitably used for a camera lens or the like.

  DESCRIPTION OF SYMBOLS 1 Adhesion layer, 2 Piezoelectric ceramics, 3 Vibration plate, 4 Organic particle | grains, 5 Vibrator, 6 Electrode (electrode layer), 61 Electrode (electrode layer), 62 Electrode (electrode layer), 63 Electrode (electrode layer) 7 Piezoelectric Element, 8 Resin, 9 Adhesive, 10 Protruding part, 11 Holding member, 12 Moving housing, 13 Screw, 14 Guide member, 15 Lens holding member, 16 Lens, 17 Connecting member, 18 Sensor, 19 Scale, 27 Power feeding member , 28 Mobile

Claims (9)

A vibrator having an adhesive layer between a piezoelectric element made of piezoelectric ceramics having electrodes and a diaphragm;
The adhesive layer contains a resin with organic particles having a number average particle diameter of 5 μm or more and 15 μm or less in an amount of 50 parts by mass or more and 80 parts by mass or less per 100 parts by mass of the resin. Characteristic vibrator.   The vibrator according to claim 1, wherein the organic particles have an elastic modulus of 0.48 GPa to 10.0 GPa.   The vibrator according to claim 1, wherein the piezoelectric ceramic is lead zirconate titanate (PZT).   The vibrator according to claim 1, wherein the electrode is a silver electrode.   The vibrator according to claim 1, wherein the resin is a thermosetting resin.   The vibrator according to claim 5, wherein the thermosetting resin is an epoxy resin or an acrylic resin.   The vibrator according to claim 1, wherein a thickness of the adhesive layer is 4.1 μm or more and 14.8 μm or less.   An ultrasonic motor that moves by bringing the vibrator according to claim 1 and a moving body into frictional contact.   An optical apparatus having the optical member mechanically connected to the ultrasonic motor according to claim 8.

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