Nikon Corporation

Toshikazu Morioke

Takatoshi Ashizawa

Shinji Nishihara

Kazuyasu Oone

Noise produced during phase-difference changes is minimized without decreasing the responsiveness of a vibration-wave motor. A lens-side MCU for a lens barrel controls a drive apparatus that applies a drive voltage to the vibration-wave motor by outputting an A-phase drive signal and a B-phase drive signal thereto. The lens-side MCU uses, for example, a drive-voltage setting unit and a duty-cycle change unit to change the drive voltage. Also, the lens-side MCU is provided with a phase-difference change unit that changes the phase difference between the A-phase drive signal and the B-phase drive signal. When driving the vibration-wave motor, the lens-side MCU changes the drive voltage to V, and when the phase-difference change unit is changing the aforementioned phase difference, the drive voltage is changed to V, Vbeing greater than zero and less than V.

Drive apparatus, drive method, and optical device

Noise produced during phase-difference changes is minimized without decreasing the responsiveness of a vibration-wave motor. A lens-side MCU for a lens barrel (controls a drive apparatus that applies a drive voltage to the vibration-wave motor by outputting an A-phase drive signal and a B-phase drive signal thereto. The lens-side MCU uses, for example, a drive-voltage setting unit and a duty-cycle change unit to change the drive voltage. Also, the lens-side MCU is provided with a phase-difference change unit that changes the phase difference between the A-phase drive signal and the B-phase drive signal. When driving the vibration-wave motor, the lens-side MCU changes the drive voltage to Vreg, and when the phase-difference change unit is changing the aforementioned phase difference, the drive voltage is changed to V, Vbeing greater than zero and less than Vreg.

A vibration actuatorcomprises an elastic bodythat generates vibration waves in accordance with driving of an element, and a relative movement member that is in pressure contact with the bodyand is relatively moved with respect to the bodyby the vibration waves. A plurality of grooveare formed at the relative movement member side of the body, and depths of the groovein a direction orthogonal to a relative movement direction of the relative movement member vary along the relative movement direction of the relative movement member.

Vibration actuator, lens barrel, and camera

A vibrational wave motor which can realize a suitable drive performance and can be driven quietly. The vibrational wave motor includes: an electromechanical-conversion element excited by a driving signal; a vibrating element joined with the electromechanical-conversion element, and having a drive surface where a progressive vibrational wave is generated by the excitation; a relative motion member having a sliding surface pressure-contacting the drive surface of the vibrating element, and which is driven by the wave; and a driving device for providing the driving signal to the electromechanical-conversion element, wherein: the driving device provides the driving signal to the electromechanical-conversion element, the driving signal generating the wave satisfying a-value/&#x3bb;&#x2266;0.00025 in the drive surface, where a vibration amplitude generated in the drive surface of the vibrating element is a-value, and a wavelength generated in the drive surface of the vibrating element is &#x3bb;.

Vibrational wave motor, lens barrel and camera

To provide a vibration actuator having good driving performance even when miniaturized, and a lens barrel and camera provided with the same. A first aspect of the present invention is to provide a vibration actuator comprising, an electromechanical conversion element, having a first joining face, and which is subject to excitation, an elastic body having a second joining face which is joined to the first joining face, and a driving face which gives rise to vibration waves as a result of said excitation, and a relative moving member, having a contact face which is in pressure contact with the driving face, which is driven by the vibration waves, and which moves relative to the elastic body, wherein an outer shape of said first joining face has a shape which differs from an outer shape of said contact face.

Vibration actuator, lens barrel and camera

A vibration actuator driving device includes a plurality of wiring sections and a supply controller. The plurality of wiring sections are disposed correspondingly to a plurality of electrically independent electrodes of an electromechanical conversion element. The wiring sections input driving signals to drive the electromechanical conversion element. The supply controller is capable of independently supplying a driving signal for each respective wiring section.

Vibration actuator driving device, lens barrel, camera, method of manufacturing electromechanical conversion element, method of manufacturing vibration actuator, and method of driving vibration actuator

To provide an electromechanical conversion element, a vibration actuator, a vibration actuator driving device, a lens barrel and a camera, which facilitate the achievement of the desired drive characteristics. An electromechanical conversion element comprising: a piezoelectric body having a polarization part polarized in a certain direction; and a plurality of separately formed electrodes on a continuous region of the polarization part.

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Kawasaki, Japan

Toshikazu Morioke