Abstract: An actuator used with an optical pickup includes: a base on which a holder is fixed; a lens holder in which a plurality of installation holes are formed such that a plurality of objective lenses to record and/or reproduce optical discs having different recording densities are installed at different heights; a support member, which movably supports the lens holder, having one end coupled to the lens holder and the other end coupled to the holder; and a magnetic circuit which drives the lens holder in focusing and tracking directions. The plurality of installation holes include a first installation hole in which a first objective lens for at least one type of low density optical disc is installed, and a second installation hole in which a second objective lens for a higher density optical disc than the low density optical disc is installed.

Abstract: An optical pickup device to provide a stable operation in both low-speed and high-speed modes by controlling a change in natural frequency, the optical pickup device including: a lens holder to support an objective lens; a supporting unit spaced apart from the lens holder; and a plurality of suspension members each having one end fixed to the lens holder and another end supported by the supporting unit to enable a movement of the lens holder, wherein the supporting unit includes a fixing member, a coupling portion provided in the fixing member to couple each suspension member, magnetic fluid received in the coupling portion, and an excite device to apply a magnetic field to the magnetic fluid.

Abstract: An actuator used with an optical pickup includes: a base on which a holder is fixed; a lens holder in which a plurality of installation holes are formed such that a plurality of objective lenses to record and/or reproduce optical discs having different recording densities are installed at different heights; a support member, which movably supports the lens holder, having one end coupled to the lens holder and the other end coupled to the holder; and a magnetic circuit which drives the lens holder in focusing and tracking directions. The plurality of installation holes include a first installation hole in which a first objective lens for at least one type of low density optical disc is installed, and a second installation hole in which a second objective lens for a higher density optical disc than the low density optical disc is installed.

Abstract: An optical pickup apparatus including a swing arm pivotably installed in a tracking direction with respect to a disc, and an optical pickup unit supported by the swing arm and driven in a focusing direction, wherein the optical pickup unit includes a laser diode, an objective lens to focus light emitted from the laser diode on a recording surface of the disc, and a heat sink plate to dissipate heat generated from the laser diode, wherein the heat sink plate is provided close to the disc so as to be directly exposed to wind generated during rotation of the disc.

Abstract: An optical pick-up actuator capable of a tilt operation. The optical pick-up actuator has a triaxial magnetic driving portion installed on a movable portion and a supporting portion to move the movable portion in a focusing direction and a tracking direction and tilt the movable portion. The triaxial magnetic driving portion includes a pair of focusing/tilting driving magnets, a pair of tracking driving magnets, focusing coils, a pair of tilt coils, and a pair of tracking coils. The pair of tilt coils installed on the movable portion each face one of the pair of focusing/tilting driving magnets and are wired independently from the pair of focusing coils.

Abstract: A compatible optical pickup compatibly using a high density recording medium and at least one low density recording medium, includes an objective lens to form a light spot suitable for use on a recording surface of the high density recording medium by focusing a corresponding incident light beam with a high NA suitable for the high density recording medium and a light spot suitable for use on another recording surface of the low density recording medium by focusing another corresponding incident light beam, and an actuator provided to apply tilt to the objective lens. The light beam for the low density recording medium is incident on the objective lens as a divergent beam. When the objective lens is shifted in a radial direction, a tilt is applied to the objective lens corresponding to the shift.

Abstract: An optical pickup including an optical member which inhibits interference light reflected from an adjacent layer from being received by a photodetector when an optical information storage medium includes a plurality of recording layers on at least one side thereof. The optical pickup suppresses a photodetector, especially first and second sub-photodetectors of the photodetector, from receiving the interference light reflected from the adjacent layer.

Abstract: An actuator of an optical disk system and an apparatus producing a signal for driving the actuator, the actuator including a light source, with which information is recorded on or reproduced from an optical disk surface. In the actuator, an inner focusing coil and an outer focusing coil are installed near an inner boundary and an outer boundary, respectively, of the optical disk surface. A first signal wire is connected to a first port of the inner focusing coil and transmits an inner coil signal. A second signal wire is connected to a first port of the outer focusing coil and transmits an outer coil signal. A common signal wire is connected to a second port of the inner focusing coil and a second port of the outer focusing coil and transmits a common reference signal. Thus, a simple, inexpensive 8-wire actuator can be obtained.

Abstract: An actuator for an optical pickup having a base on which a holder is fixed, a bobbin, a support member, and a magnetic circuit. Pluralities of installation holes are formed in the bobbin such that a plurality of objective lenses to record and/or reproduce optical discs having different recording densities are installed at different heights. The support member has one end coupled to the bobbin and the other end coupled to the holder movably supports the bobbin. The magnetic circuit drives the bobbin in focusing and tracking directions. The magnetic circuit is divided into a first magnetic circuit to drive the objective lenses in the focusing direction, and a second magnetic circuit to drive the objective lenses in the tracking direction, thereby reducing the weight of a moving portion.

Abstract: A disk cartridge has a reflection portion to identify a kind of a disk in the disk cartridge. A disk drive apparatus has an optical detector to identify the kind of the disk by irradiating a beam to the reflection portion and detecting the reflected beam. The disk cartridge and the disk drive apparatus provide identification marks for identifying the kind of the disk by varying the angle and amount of a beam reflected from the reflection portions on the disk cartridge. Therefore, the kind of a disk and the type of a disk format are identified as well as the storage capacity of the disk.

Abstract: A compact high-density optical disc capable of securing recording/reproducing characteristics and high-density recording capacity. The high-density optical disc has a whole diameter of 80 mm or less to 28 mm, a whole thickness in a range of 0.3–0.7 mm, and a position where data starts being recorded in a range of 27–45 mm of the diameter. Thus, an existing disc drive can be used, the size of the high-density optical disc can be reduced, and high-density recording capacity can be secured.

Abstract: An optical pick-up device is provided that reduces aberrations in light irradiated from an optical recording meidu. The device includes a light source that outputs light for recordation and reproduction of information onto the optical recording medium. An objective lens irradiates the light onto the optical recording medium by concentrating the light. An actuator adjusts the movement of the objective lens to focus the light on at least one or more layers of the optical recording medium. A controller moves the objective lens to substantially reduce the aberration occurring in the light irradiated from the optical recording medium by driving the actuator, such that aberrations, such as asymmetrical aberrations or coma aberrations, may be reduced and corrected.

Abstract: An optical pickup actuator for use with a recording medium includes a swing arm pivoting in a tracking direction with respect to the recording medium, a first driving unit pivoting the swing arm, an optical pickup facing the recording medium, an elastic member having one end fixed to the swing arm and a free end portion elastically deformable in a focus direction with respect to the recording medium, wherein the optical pickup is coupled to the free end portion of the elastic member, and a second driving unit deforming and driving the elastic member.

Abstract: An optical pickup actuator, including a lens holder movably installed on a base, and mounted with an objective lens to transmit an incident light to an optical information recording medium, and a magnetic circuit to independently drive the lens holder in a focusing direction, a tilting direction and a tracking direction, respectively.

Abstract: An optical pickup actuator independently drivable in focusing, tilting and tracking directions. The optical pickup includes a lens holder movably installed on a base, and mounted with an objective lens for transmitting an incident light to an optical information recording medium; and a magnetic circuit to independently driving the lens holder in the focusing, tilting and tracking directions. The magnetic circuit includes opposing magnets; a focusing coil and tilting coils interposed between the magnets, mounted inside the lens holder, and wound around respective axes parallel to the focusing direction; and a plurality of tracking coils mounted outside the lens holder, interposed between the magnets and wound around respective axes transverse to the focusing direction. The magnetic fields of the magnets are guided by outer yokes partially encompassing the magnets and inner yokes positioned within the focusing coil and the tilting coils.

Abstract: An optical pickup apparatus includes an objective lens that focuses light on an optical recording medium; an actuator that drives the objective lens in a direction of an optical axis of the objective lens toward or away from an optical recording medium in response to an input voltage applied to the actuator; an actuator driven distance sensor that senses a distance the actuator moves according to time or the input voltage applied to the actuator; an input voltage calculator that calculates an input voltage to be applied to the actuator that compensates for a hysteresis phenomenon that occurs during movement of the actuator based on the distance sensed by the actuator driven distance sensor; and a controller that controls operation of the actuator according to the input voltage calculated by the input voltage calculator.

Abstract: An optical pickup of an optical recording and reproducing apparatus includes a plurality of object lenses used to record and or reproduce information from/to various types of optical recording media of different recording densities; an actuator driving the object lenses in a focusing direction and supporting the object lenses to have rolling during movement in the focusing direction; and a pickup base installed to movably go and return in a radial direction of an optical recording medium, and the actuator forming a predetermined angle with respect to the pickup base.

Abstract: A disk cartridge and a disk drive apparatus. The disk cartridge has a reflector to identify the type of disk, and the disk drive apparatus has an optical emitter/detector to irradiate light on the reflector and detect light reflected from the reflector to identify the type of disk. A large number of identification marks can be provided by changing the angle of reflection and the amount of light reflected from the reflector. Accordingly, disks of various capacities, products and formats can be individually identified.

Abstract: An optical pickup actuator is provided. The actuator comprises a bobbin, on which one or more objective lenses are mounted for allowing light to be incident onto an optical information storage medium, and which is supported by a support member to be movable in relation to a base. The actuator also comprises a magnetic circuit for independently driving the bobbin in focusing and tilt directions.

Abstract: An optical pickup actuator and a method of assembling the same is provided. The method of assembling the optical pickup actuator comprises the steps of providing a blade having at least one objective lens mounting area and an aberration correcting mechanism mounting area, arranging an objective lens in the objective lens mounting area, positioning an aberration correcting mechanism in the aberration correcting mechanism mounting area such that the central point of the aberration correcting mechanism coincides with the central point of the objective lens, tuning the aberration correction mechanism, and adhering the aberration correcting mechanism using an adhesive.