Vibrator, ultrasonic motor, and optical device
A vibrator includes a piezoelectric element including a piezoelectric ceramic having an electrode, a vibration plate, and an adhesive layer between the piezoelectric element and the vibration plate, wherein the adhesive layer is obtained by a resin containing 50 parts by mass or more and 80 parts by mass or less of organic particles having a number average particle size of 5 μm or more and 15 μm or less, relative to 100 parts by mass of the resin.
1. A vibrator comprising:
a piezoelectric element including a piezoelectric ceramic having an electrode;
a vibration plate; and
an adhesive layer between the piezoelectric element and the vibration plate,
wherein the adhesive layer is obtained by a resin containing 50 parts by mass or more and 80 parts by mass or less of organic particles having a number average particle size of 5 μm or more and 15 μm or less, relative to 100 parts by mass of the resin.
2. The vibrator according to claim 1 , wherein an elastic modulus of the organic particles is 0.48 GPa or more and 10.0 GPa or less.
3. The vibrator according to claim 1 , wherein the piezoelectric ceramic is lead zirconate titanate (PZT).
4. The vibrator according to claim 1 , wherein the electrode is a silver electrode.
5. The vibrator according to claim 1 , wherein the resin is a thermosetting resin.
6. The vibrator according to claim 5 , wherein the thermosetting resin is an epoxy resin or an acrylic resin.
7. The vibrator according to claim 1 , wherein a thickness of the adhesive layer is 4.1 μm or more and 14.9 μm or less.
8. An ultrasonic motor comprising:
the vibrator according to claim 1 ; and
a moving member in contact with the vibrator.
9. An optical device comprising:
the ultrasonic motor according to claim 8 ; and
optical members dynamically connected to the ultrasonic motor.
10. A method for manufacturing a vibrator including a piezoelectric element including a piezoelectric ceramic having an electrode, a vibration plate, and an adhesive layer between the piezoelectric element and the vibration plate, the method comprising:
applying an adhesive to the vibration plate; and
providing an adhesive layer by curing the adhesive while pressurizing the piezoelectric element against a surface of the vibration plate to which the adhesive has been applied,
wherein the adhesive is obtained by a precursor of a resin 1 containing 50 parts by mass or more and 80 parts by mass or less of organic particles having a number average particle size of 5 μm or more and 15 μm or less, relative to 100 parts by mass of the precursor of the resin.