Abstract: A magnetic circuit and an optical recording and/or reproducing apparatus employing the magnetic circuit, having: a magnet with first and second magnetic portions adjacent to each other and opposite in polarity, and third and fourth magnetic portions surrounding the first and second magnetic portions, respectively, and have opposite polarities to the first and second magnetic portions, respectively; and at least one of a tracking coil unit or a focus coil unit. The tracking coil unit has first through third tracking coils arranged in a tracking direction so that each tracking coil interacts with two of the first through fourth magnetic portions. The focus coil unit has first through fourth focus coils, two of which are disposed in a focus direction to interact with the first and third magnetic portions, and the remaining two of which are disposed in the focus direction to interact with second and fourth magnetic portions.

Abstract: An optical pickup actuator which includes a base, a blade having an objective lens mounted thereon, a plurality of suspensions supporting the blade to be movable with respect to the base and forming an electroconductive path, and a magnetic circuit driving the blade according to a driving signal applied through the respective suspensions. The magnetic circuit includes a magnet fixed to the base, and a fine pattern coil installed on the blade at a position facing the magnet and having a track pattern coil, a focus pattern coil, and a tilt pattern coil independently driven by current applied through the suspensions and providing driving forces in a track direction, a focus direction, and a tilt direction of the blade.

Abstract: A magnetic circuit, an optical pickup actuator, an optical recording and/or reproducing apparatus using the magnetic circuit, and method of the same, wherein the magnetic circuit includes a plurality of focus coil units each of which includes a first focus coil and a second focus coil, and a magnet including a plurality of magnet portions which interact with the plurality of focus coil units and each of which is polarized in a direction opposite to adjacent magnet portions thereamong. Here, electromagnetic forces act on the first and second focus coils in each focus coil unit in a same direction in response to focus driving signals and in opposite directions in response to tilt driving signals, with the first and second focus coils in each focus coil unit have different effective coil lengths.

Abstract: A recording/reproducing apparatus and an optical pickup actuator, and corresponding methods, for driving a bobbin in a focusing direction, a tracking direction or a tilting direction by use of a magnetic driving unit movably supported by a support member, where an object lens is mounted on the bobbin and a plurality of slits are formed on side walls of the bobbin. According to embodiments of the present invention, a secondary resonant frequency and a value of a secondary resonant peak are increased, thereby improving a gain margin.

Abstract: An optical recording and/or reproducing apparatus with an optical pickup actuator having high thrust. The optical pickup actuator may include a lens holder which holds an objective lens and is movably supported by a supporting unit, and a magnetic driving unit which drives the lens holder in a focusing direction, a tracking direction, and/or a tilting direction. The magnetic driving unit includes a surface-triple pole magnet portion and a coil portion. The surface-triple pole magnet portion has a plurality of polarized, i.e., differently magnetized, areas formed by facing sides of two magnets among three magnets. The coil portion includes tracking coils and tilt coils disposed to interact with the polarized areas of the surface-triple pole magnet portion and a focusing coil disposed to interact with a non-polarized area of the surface-triple pole magnet portion.

Abstract: An optical pickup actuator includes a bobbin, support members, and a pair of magnetic circuits. An objective lens is mounted on the bobbin. The support members have first ends fixed on sides of the bobbin and second ends fixed to a holder placed on a portion of a base to allow the bobbin to move with respect to the base. The magnetic circuits are installed on two sides of the bobbin and on the base. Each magnetic circuit includes a tracking coil which moves the bobbin in a tracking direction, a plurality of focusing/tilting coils which moves the bobbin in at least one direction of a focusing direction and a tilting direction having a focusing component, and a magnet which faces the focusing/tilting coils and the tracking coil and have a polarized structure to move the bobbin in the tracking direction and at least one direction of the focusing direction and the tilting direction having the focusing component.

Abstract: A molded coil device includes a coil comprised of a plurality of turns of a conductive material through a plurality of planes and an integral body comprised of an insulating and nonmagnetic material burying the coil. The coil is first formed and thereafter is sintered/pressed with the insulating and nonmagnetic material to form the integral body. The molded coil device is advantageously applied within an optical pickup actuator of an optical disc drive.

Abstract: A pickup actuator of a disc drive includes a pair of magnets, each facing a respective side of a bobbin and having a middle region with a first polarity and side regions with a second polarity opposite of the first polarity. The pickup actuator includes a plurality of tracking coils disposed on the respective sides of the bobbin facing the magnets. Each tracking coil has two effective coil portions with one facing the middle region and the other facing one of the side regions of the magnet, for higher sensitivity. The magnets are disposed at two sides of a bobbin for lower cost and complexity of manufacture.

Abstract: An optical pickup actuator which includes a base, a blade having an objective lens mounted thereon, a plurality of suspensions supporting the blade to be movable with respect to the base and forming an electroconductive path, and a magnetic circuit driving the blade according to a driving signal applied through the respective suspensions. The magnetic circuit includes a magnet fixed to the base, and a fine pattern coil installed on the blade at a position facing the magnet and having a track pattern coil, a focus pattern coil, and a tilt pattern coil independently driven by current applied through the suspensions and providing driving forces in a track direction, a focus direction, and a tilt direction of the blade.

Abstract: An optical recording and/or reproducing apparatus with an optical pickup actuator having high thrust. The optical pickup actuator may include a lens holder which holds an objective lens and is movably supported by a supporting unit, and a magnetic driving unit which drives the lens holder in a focusing direction, a tracking direction, and/or a tilting direction. The magnetic driving unit includes a surface-triple pole magnet portion and a coil portion. The surface-triple pole magnet portion has a plurality of polarized, i.e., differently magnetized, areas formed by facing sides of two magnets among three magnets. The coil portion includes tracking coils and tilt coils disposed to interact with the polarized areas of the surface-triple pole magnet portion and a focusing coil disposed to interact with a non-polarized area of the surface-triple pole magnet portion.

Abstract: Provided is an optical pickup actuator including a blade, a plurality of wires, coils, magnets, and connectors. The blade has an objective lens. The plurality of wires support the blade so that the blade moves around a predetermined holder. The coils are installed on the blade. The magnets interact with a current flowing through the coils to generate an electromagnetic force. The connectors electrically connect the wires and the coils so that a power supply supplies a current to the coils via the wires. The connectors include conductive plating terminals that are connected to the coils and installed on the body of the blade so that ends of the wires are connected to the connectors.

Abstract: An optical pickup actuator including a coil, a first magnet, and a second magnet. The coil is installed in a blade holding an objective lens. The first magnet is positioned inside a cavity formed in the center of the coil. The second magnet is installed outside the cavity to face the first magnet. The outer surface of the first magnet facing the coil is polarized into a first pole and inner surface of the first magnet is polarized into a second pole.

Abstract: An optical pickup actuator includes a bobbin, support members, and a pair of magnetic circuits. An objective lens is mounted on the bobbin. The support members have first ends fixed on sides of the bobbin and second ends fixed to a holder placed on a portion of a base to allow the bobbin to move with respect to the base. The magnetic circuits are installed on two sides of the bobbin and on the base. Each magnetic circuit includes a tracking coil which moves the bobbin in a tracking direction, a plurality of focusing/tilting coils which moves the bobbin in at least one direction of a focusing direction and a tilting direction having a focusing component, and a magnet which faces the focusing/tilting coils and the tracking coil and have a polarized structure to move the bobbin in the tracking direction and at least one direction of the focusing direction and the tilting direction having the focusing component.

Abstract: An optical pickup actuator includes a bobbin, support members, and a pair of magnetic circuits. An objective lens is mounted on the bobbin. The support members have first ends fixed on sides of the bobbin and second ends fixed to a holder placed on a portion of a base to allow the bobbin to move with respect to the base. The magnetic circuits are installed on two sides of the bobbin and on the base. Each magnetic circuit includes a tracking coil which moves the bobbin in a tracking direction, a plurality of focusing/tilting coils which moves the bobbin in at least one direction of a focusing direction and a tilting direction having a focusing component, and a magnet which faces the focusing/tilting coils and the tracking coil and have a polarized structure to move the bobbin in the tracking direction and at least one direction of the focusing direction and the tilting direction having the focusing component.

Abstract: A magnetic circuit, an optical pickup actuator, an optical recording and/or reproducing apparatus using the magnetic circuit, and method of the same, wherein the magnetic circuit includes a plurality of focus coil units each of which includes a first focus coil and a second focus coil, and a magnet including a plurality of magnet portions which interact with the plurality of focus coil units and each of which is polarized in a direction opposite to adjacent magnet portions thereamong. Here, electromagnetic forces act on the first and second focus coils in each focus coil unit in a same direction in response to focus driving signals and in opposite directions in response to tilt driving signals, with the first and second focus coils in each focus coil unit have different effective coil lengths.

Abstract: A magnetic circuit and an optical recording and/or reproducing apparatus employing the magnetic circuit, having: a magnet with first and second magnetic portions adjacent to each other and opposite in polarity, and third and fourth magnetic portions surrounding the first and second magnetic portions, respectively, and have opposite polarities to the first and second magnetic portions, respectively; and at least one of a tracking coil unit or a focus coil unit. The tracking coil unit has first through third tracking coils arranged in a tracking direction so that each tracking coil interacts with two of the first through fourth magnetic portions. The focus coil unit has first through fourth focus coils, two of which are disposed in a focus direction to interact with the first and third magnetic portions, and the remaining two of which are disposed in the focus direction to interact with second and fourth magnetic portions.

Abstract: A recording/reproducing apparatus and an optical pickup actuator, and corresponding methods, for driving a bobbin in a focusing direction, a tracking direction or a tilting direction by use of a magnetic driving unit movably supported by a support member, where an object lens is mounted on the bobbin and a plurality of slits are formed on side walls of the bobbin. According to embodiments of the present invention, a secondary resonant frequency and a value of a secondary resonant peak are increased, thereby improving a gain margin.

Abstract: A pickup actuator of a disc drive includes a pair of magnets, each facing a respective side of a bobbin and having a middle region with a first polarity and side regions with a second polarity opposite of the first polarity. The pickup actuator includes a plurality of tracking coils disposed on the respective sides of the bobbin facing the magnets. Each tracking coil has two effective coil portions with one facing the middle region and the other facing one of the side regions of the magnet, for higher sensitivity. The magnets are disposed at two sides of a bobbin for lower cost and complexity of manufacture.

Abstract: An optical pickup actuator including a lens holder holding an objective lens and which is supported by a suspension to be movable with respect to a base, and a magnetic circuit which drives the objective lens, and an optical recording and/or reproducing apparatus using the same. The magnetic circuit includes a pair of unipolar magnetized magnets positioned on the base to face each other, a focusing coil positioned in the lens holder to be placed between the pair of unipolar magnetized magnets, a plurality of tracking coils positioned at a side of the focusing coil facing the unipolar magnetized magnet, and a plurality of tilt coils, which, are positioned in an upper portion and/or a lower portion of the focusing coil with respect to an upper direction and a lower direction of a central axis of the objective lens.

Abstract: A molded coil device includes a coil comprised of a plurality of turns of a conductive material through a plurality of planes and an integral body comprised of an insulating and nonmagnetic material burying the coil. The coil is first formed and thereafter is sintered/pressed with the insulating and nonmagnetic material to form the integral body. The molded coil device is advantageously applied within an optical pickup actuator of an optical disc drive.