Abstract: Provided is a position sensing device including a sensing unit that is mounted on one side of a lens barrel, which is inserted into a lens housing portion of a base so as to be vertically driven, and includes a light receiving section and a light emitting section which are provided to face each other; a driven grid that has a plurality of slits formed therein and is mounted on the lens barrel; and a fixed grid that has a plurality of slits formed therein and is fixed and coupled to the inside of the sensing unit.

Abstract: Provided is a lens driving module including a housing that has a lens barrel housing portion provided therein; a lens barrel that has a bearing contact portion and a guide portion formed on the outer circumferential surface thereof and is mounted in the lens barrel housing portion of the housing; a piezoelectric motor that is mounted in one outer corner of the housing, which corresponds to the guide portion of the lens barrel, among the outer corners of the housing, and provides a driving force to the lens barrel; and a power connection member that is bent so as to cover the piezoelectric motor and the outer circumferential surface of the housing and is coupled to the housing.

Abstract: Provided is a lens driving module including a housing that has a lens barrel housing portion provided in the central portion thereof, the lens barrel housing portion having a bearing coupling portion and a guide coupling portion provided therein, and a through-hole formed in one corner thereof where the guide coupling portion is formed; a lens barrel that has a bearing contact portion and a guide portion formed on the outer circumferential surface thereof and is mounted in the lens barrel housing portion of the housing such that the bearing contact portion and the guide portion correspond to the bearing coupling portion and the guide coupling portion of the lens barrel housing portion, respectively; a piezoelectric motor that is mounted in the through-hole formed in one outer corner of the housing, which corresponds to the guide portion of the lens barrel, among the outer corners of the housing; a power connection member that is attached on the outer surface of the piezoelectric motor and of which only a pred

Abstract: A piezoelectric motor for generating an elliptic motion by adding a longitudinal vibration to a bending-direction vibration is provided. The piezoelectric motor includes a piezoelectric member which generates a first vibration mode and a second vibration mode simultaneously by an applied power and a frictional member of which a portion is insertedly attached into a concave portion indentedly formed on one side of the piezoelectric member, wherein the frictional member is in an elliptic motion by the vibration generated by the piezoelectric member, so that an influence of the attachment of the frictional member to a resonance frequency can be minimized. Accordingly, a driving efficiency of the piezoelectric motor can be improved. In addition, attachment strength of the frictional member can be improved.

Abstract: The present invention relates to a lens driving device includes a lens receiving part with a lens disposed therein, having first and second extension parts formed at opposed sides in a predetermined interval from each other. The lens driving device also includes an actuator having a body between the first and second extension parts. The actuator body has first and second output members contacting the first and second extension parts of the lens receiving part at opposed ends thereof, and thereby expands, contracts and bends when power is applied. The lens driving device also includes a preload member compressing the first and second extension parts against the actuator body to maintain a status of pressed contact. The lens driving device further includes a guide part for guiding the movement of the lens receiving part in an optical axis direction.

Abstract: A piezoelectric vibrator that generates an elliptical motion using a combination of a longitudinal vibration and a flexural vibration includes a piezoelectric element, three side electrodes, and a power transmission member. The piezoelectric element includes three piezoelectric element layers. The first and second side electrodes electrically connect electrode patterns formed in a diagonal direction among the electrode patterns formed in the first and third piezoelectric element layers of the piezoelectric element, and the third side electrode electrically connects an internal ground electrode of the second piezoelectric element layer to the bottom electrode of the third piezoelectric element layer. The power transmission member is formed in one side of the piezoelectric element to transmit vibration generated from the piezoelectric element to the outside.

Abstract: A stator and a piezo ultrasonic motor including the same are provided. The piezo ultrasonic motor includes a stator including an elastic body having a flat portion at its outer surface and a central hole penetrating the center of the stator with a predetermined size, and a piezoelectric body including a first internal piezoelectric body and a second internal piezoelectric body integrally disposed parallel to each other in a longitudinal direction of the flat portion and providing an external force deforming the elastic body when an AC voltage is applied, a rotor inserted in the central hole and including a contact frictionally contacting an inner surface of the central hole, an elastic part providing an elastic force maintaining close attachment of the contact to the stator. Accordingly, the manufacturing cost decreases by reducing the number of elements and simplifying a structure, and a stable driving characteristic can be achieved.

Abstract: There are provided a piezoelectric actuator and a lens driving apparatus having the piezoelectric actuator. The lens driving device includes: a lens barrel having a lens hole where at least one lens is disposed, and having a tip friction member on an outer surface thereof; a base having a guiding part guiding the lens barrel to move along an optical axis direction; a piezoelectric actuator having a piezoelectric body disposed at an edge of the base to apply a driving force when a power is applied, the piezoelectric body having at least one friction member at one side thereof to be in contact with the tip friction member; and a preload member applying an elastic force for elastically supporting the piezoelectric actuator against the lens barrel to keep the tip friction member and the friction member in contact with each other.

Abstract: A lens driving device includes a lens barrel having a lens holder and an extension part extended from the lens holder. The device also includes a piezoelectric vibrator with a piezoelectric body flexed and bent in response to power application with a friction member in contact with the extension part, thereby providing driving power for transporting the lens barrel. The device further includes a preload member having a free end in resilient contact with a rear end of the piezoelectric body to compress the piezoelectric vibrator against the extension part and a guiding part for guiding the transport of the lens barrel in the optical axis direction. This allows a simplified and miniaturized structure, a large transport range with low input power to achieve excellent resolution of positioning, minimal loss of driving power, simplified mechanism for guiding the transport of the lens, and accurate and stable transport of the lens.

Abstract: The invention provides a lens transfer device including at least one lens and a lens barrel. The lens barrel has a lens receiving part with the lens arranged in an inner space thereof and an extension extending radially from an outer surface of the lens receiving part. An actuator has a body and an output member at a leading end of the actuator to contact the extension, and is adapted to expand/contract and bend in response to an external supply voltage to provide a driving force necessary for transfer of the lens barrel through the output member. A pressing member has a free end contacting a rear end of the actuator to force the actuator against the extension, and a guide guides the transfer of the lens barrel along an optical axis.

Abstract: A lens driving device including: a lens barrel having at least one lens therein and provided with a friction member; a housing for housing the lens barrel therein; an actuator having a piezoelectric body disposed at an edge of the housing to apply a driving force, the piezoelectric body having at least one output member provided at one side thereof to be in contact with the friction member; a preload member disposed between the edge of the housing and the actuator to apply an elastic force toward the lens barrel; and a guiding part disposed between the housing and the lens barrel to guide the lens barrel to move in an optical axis direction. The lens driving device is simplified in a driving mechanism and thus reduced in size, while experiencing minimum loss of a driving power and ensuring more accurate and stable movement of the lens.

Abstract: A piezoelectric motor for generating an elliptic motion by adding a longitudinal vibration to a bending-direction vibration is provided. The piezoelectric motor includes a piezoelectric member which generates a first vibration mode and a second vibration mode simultaneously by an applied power and a frictional member of which a portion is insertedly attached into a concave portion indentedly formed on one side of the piezoelectric member, wherein the frictional member is in an elliptic motion by the vibration generated by the piezoelectric member, so that an influence of the attachment of the frictional member to a resonance frequency can be minimized. Accordingly, a driving efficiency of the piezoelectric motor can be improved. In addition, attachment strength of the frictional member can be improved.

Abstract: There is provided a flat type piezoelectric ultrasonic motor for generating a rotation force to a rotor by ultrasonic vibrations. In the piezoelectric ultrasonic motor, a vibrator is formed of elastic material at a given size, a plurality of piezoelectric plates are attached on the vibrator, a rotor is drivingly connected to the vibrator thereby to be rotated, and a power source unit applies driving voltages to the piezoelectric plates. The piezoelectric plates are arranged on quartered surface areas of the vibrator in such a way that longitudinal axes of neighboring piezoelectric plates form a given angle therebetween and opposing piezoelectric plates have opposite polarizations, and the power source unit applies alternating driving voltages to the piezoelectric plates thereby to make the rotor rotated, thereby making it possible to simplify the piezoelectric plates' shape, minimize its size and enhance its driving efficiency.

Abstract: The present invention relates to a ceramic tube type ultrasonic motor having a stator including a tube-type elastic body that is formed of a ceramic material; and a plurality of piezoelectric diaphragms that are attached on the outer peripheral surface of the elastic body in a longitudinal direction thereof and to which voltages having a phase difference are respectively applied and a rotor that is rotated by the friction with the elastic body flexurally vibrating due to the voltages applied to the plurality of piezoelectric diaphragms.

Abstract: Provided is a piezoelectric vibrator that can finely drive a device by generating an elliptical motion using a combination of a longitudinal vibration and a flexural vibration. The piezoelectric vibrator can also provide high efficiency and be manufactured at low cost by using a simpler structure. The piezoelectric vibrator includes a piezoelectric element, first to third side electrodes, and a power transmission member. The piezoelectric element includes: a first piezoelectric element layer having a bisected top electrode formed thereon; a second piezoelectric element provided under the first piezoelectric element layer and having an internal ground electrode formed thereon; and a third piezoelectric element provided under the second piezoelectric element layer, the third piezoelectric element having an internal electrode symmetrical with the top electrode with respect to a stack plane, and a bottom electrode formed in a plane opposite to the plane where the internal electrode is formed.

Abstract: A auto-focusing method comprises setting a plurality of active windows composed of a central window and a plurality of peripheral windows surrounding the central window and allocating weights to the plurality of active windows so as to calculate an auto-focus value for each step; calculating a rate of change in auto-focus value between a previous step and a current step from the auto-focus value calculated for each step; comparing the calculated rate of change in auto-focus value with preset auto-focus reference values and then changing a step size in accordance with the comparison result; transferring a lens to a position corresponding to the changed step size; repeating the above processes from the setting of the plurality of active windows to the transferring of the lens until the auto-focus value of the previous step becomes larger than that of the current step and then determining whether the maximum auto-focus value is detected or not; and transferring the lens to a position corresponding to the maximum

Abstract: A lens driving device includes a lens barrel having a lens holder and an extension part extended from the lens holder. The device also includes a piezoelectric vibrator with a piezoelectric body flexed and bent in response to power application with a friction member in contact with the extension part, thereby providing driving power for transporting the lens barrel. The device further includes a preload member having a free end in resilient contact with a rear end of the piezoelectric body to compress the piezoelectric vibrator against the extension part and a guiding part for guiding the transport of the lens barrel in the optical axis direction. This allows a simplified and miniaturized structure, a large transport range with low input power to achieve excellent resolution of positioning, minimal loss of driving power, simplified mechanism for guiding the transport of the lens, and accurate and stable transport of the lens.

Abstract: The present invention relates to a lens driving device includes a lens receiving part with a lens disposed therein, having first and second extension parts formed at opposed sides in a predetermined interval from each other. The lens driving device also includes an actuator having a body between the first and second extension parts. The actuator body has first and second output members contacting the first and second extension parts of the lens receiving part at opposed ends thereof, and thereby expands, contracts and bends when power is applied. The lens driving device also includes a preload member compressing the first and second extension parts against the actuator body to maintain a status of pressed contact. The lens driving device further includes a guide part for guiding the movement of the lens receiving part in an optical axis direction.

Abstract: In a driving and control apparatus of a piezoelectric ultrasonic motor, a controller controls a selection of a first channel or a second channel of the piezoelectric ultrasonic motor as a driving channel. A switch part selects one of the first and second channels as the driving channel and the other as a detection channel, and supplies the driving voltage to the piezoelectric ultrasonic motor through the selected driving channel. A phase detector detects a voltage outputted from the piezoelectric ultrasonic motor through the detection channel, calculates a phase deviation, and outputs a phase difference voltage corresponding to the phase deviation. A voltage controlled oscillator generates the oscillation voltage and controls a phase of the oscillation voltage according to the phase difference voltage. A frequency divider divides the oscillation voltage by two to generate the driving voltage, and supplies the divided oscillation voltage to the piezoelectric ultrasonic motor through the driving channel.

Abstract: The invention provides a lens transfer device including at least one lens and a lens barrel. The lens barrel has a lens receiving part with the lens arranged in an inner space thereof and an extension extending radially from an outer surface of the lens receiving part. An actuator has a body and an output member at a leading end of the actuator to contact the extension, and is adapted to expand/contract and bend in response to an external supply voltage to provide a driving force necessary for transfer of the lens barrel through the output member. A pressing member has a free end contacting a rear end of the actuator to force the actuator against the extension, and a guide guides the transfer of the lens barrel along an optical axis.