The driving unit includes: a first contact portion and a second contact portion that move relatively to each other while making contact with each other during driving; in which the second contact portion includes a coating layer at a contact face with the first contact portion, and the first contact portion and the second contact portion generate heat along with relative movement to vaporize a worn-away part of the coating layer.

The present disclosure describes a projector which has: an image projection portion; an image provision portion that provides a projection image to the image projection portion; a deviation movement detection portion that detects a deviation movement of the image projection portion; and an image process portion that based on detection by the deviation movement detection portion, shifts the image provided by the image provision portion in a direction where the deviation movement is corrected. According to this, even if an image projection function does not include a deviation correction function, it is possible to perform the deviation correction by means of the image process.

There is provided a piezoelectric actuator apparatus capable of moving an object to be driven at high velocity by using a piezoelectric element to apply a force to a driving member coupled to the object to be driven by a predetermined frictional force.

A piezoelectric actuator apparatus 100 is controlled and driven by inputting a driving voltage having a PWM waveform to a piezoelectric element 101 to which an inductor 27 and a resistor 28 are connected in series. The piezoelectric actuator apparatus 100 increases the velocity of the object to be driven 106 by adjusting respective values of the inductance L.sub.0 and the resistance R.sub.0 to control damping ratios, amplitudes, and resonance frequencies of the respective vibrations of the piezoelectric mechanical resonance and the piezoelectric electrical resonance, and inducing a response of the driving member 102 closer to sawtooth waves.

A vibration device includes a light-transmissive body, and a vibrator to vibrate the light-transmissive body at a vibration acceleration of equal to or more than about 1.5×10.sup.5 m/s.sup.2 and equal to or less than about 8.0×10.sup.5 m/s.sup.2.

A driving-unit operation method includes: generating pulse blocks on the basis of driving pulses; and modifying a driving signal in accordance with a position error signal. In the modifying the driving signal, when the position error signal is in a first range, the shape of the driving pulses is modified so as to form a first driving-pulse shape, and the pulse-block duty cycle is set to a first pulse-block duty cycle value, whereas when the position error signal is in a second range, the shape of the driving pulses is modified so as to form a second driving-pulse shape, and the pulse-block duty cycle is set to a second pulse-block duty cycle value.

This lens drive device is provided with: a first movable part; a second movable part; a first drive part; and a second drive part. The first drive part and the second drive part respectively have a first ultrasonic motor and a second ultrasonic motor. The first ultrasonic motor and the second ultrasonic motor are arranged on sides opposite to each other with respect an optical axis, and independently drive the first movable part and the second movable part in the optical axis direction.

A vibration-type actuator includes a vibrator, a contact body, a pressure member, a holding member, and a base. The vibrator has an elastic member and an electro-mechanical energy conversion element fixed to the elastic member. The contact body contacts the vibrator. The pressure member presses the contact body and the vibrator in a first direction. The holding member holds the vibrator and includes a support portion and at least one fitting hole portion extending in the first direction. The support portion supports the vibrator movably in the first direction. The base holds the holding member. The contact body moves relative to the vibrator in a second direction intersecting the first direction. The base includes at least one fitting protrusion portion extending in the first direction and fits in the at least one fitting hole portion.

A position detection device detects a position of a lens holder in an X-axis direction based on a change in an output value of a first magnetic sensor, a position of the lens holder in a Y-axis direction based on a change in an output value of a second magnetic sensor, and a position of the lens holder in a Z-axis direction based on the changes in the output values of the first magnetic sensor and the second magnetic sensor.

A lens drive device is provided with: a lens holder for holding a lens; an ultrasonic motor configured to move the lens holder in a direction of an optical axis; and a support part configured to support the lens holder in a state where the lens holder is urged in a direction orthogonal to the optical axis and such that the lens holder is capable of moving in the direction of the optical axis. The support part includes two pairs of support portions which are disposed respectively on two straight lines along an urging direction and parallel to each other such that the support portions of each pair holds the lend holder therebetween.

In accordance with some embodiments, a method of forming an auto-focusing device is provided. The method includes forming a cantilever beam member. The cantilever beam member has a ring shape. The method further includes forming a piezoelectric member over the cantilever beam member. The method also includes forming a membrane over the cantilever beam member. The membrane has a first region and a second region. The first region has a planar surface, and the second region is located between the first region and an inner edge of the cantilever beam member and has a plurality of corrugation structures. In addition, the method includes applying a liquid optical medium over the membrane and sealing the liquid optical medium with a protection layer.