Vibration actuator, optical device, and electronic device

An optical device comprising:

• a vibration actuator including a vibrating body including an electrical energy-mechanical energy conversion element and an elastic body, and a contact body in contact with a surface of the elastic body via a contact surface, vibration of the vibrating body causing relative movement of the vibrating body with respect to the contact body;
• an optical element;
• and
• an imaging element, at least one of the optical element and the imaging element being driven by the vibration actuator,
• wherein the contact body includes a hard material portion and a resin portion,
• the hard material portion and the resin portion are exposed to the contact surface, and
• the hard material portion includes a plurality of thin plate portions, and the resin portion is present at least in a gap between the thin plate portions.

An electronic device comprising:

• a vibration actuator including a vibrating body including an electrical energy-mechanical energy conversion element and an elastic body, and a contact body in contact with a surface of the elastic body via a contact surface, vibration of the vibrating body causing relative movement of the vibrating body with respect to the contact body;
• and
• a member driven by the vibration actuator,
• wherein the contact body includes a hard material portion and a resin portion,
• the hard material portion and the resin portion are exposed to the contact surface, and
• the hard material portion includes a plurality of thin plate portions, and the resin portion is present at least in a gap between the thin plate portions.

A member comprising:

• a hard material portion;
• and
• a resin portion,
• wherein the hard material portion and the resin portion are exposed to a surface of the member,
• the hard material portion includes a plurality of thin plate portions, and the resin portion is present at least in a gap between the thin plate portions, and
• the plurality of thin plate portions is stacked in a thickness direction of the plurality of thin plate portions.

A method of manufacturing a vibration actuator including an elastic body and a contact body in contact with the elastic body, the method comprising:

• an impregnating step of impregnating a gap between a plurality of thin plates with a resin with the plurality of thin plates arranged in a thickness direction;
• a polishing step of polishing a surface of the member impregnated with the resin to obtain a contact body having a surface to which the resin and the plurality of thin plates are exposed;
• and
• an assembling step of performing assembling such that the contact body and the elastic body are in contact with each other.