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: A four-axial driving actuator for an optical pickup with improved bobbin dynamic characteristics, in which the winding starting ports for a focus coil, tracking coil, and tilt coil are separate from one another, and the winding end ports thereof are combined as a common ground. The four-axial driving actuator includes: a base; a holder fixed on the base; a bobbin to which an objective lens is fixed; spring wires connected between the bobbin and the holder; and a magnetic driving unit driving the bobbin in the focus, track, or tilt direction with a focus coil, a tracking coil, and a tilt coil, wherein the magnetic driving unit comprises a circuit unit including winding starting ports for the focus coil, tracking coil, and tilt coil, and a common ground port at which winding end ports for the focus coil, tracking coil, and tilt coil are grounded, and the circuit unit applies a voltage to the tracking coil, tracking coil, and tilt coil.

Abstract: A disc clamping apparatus includes an upper clamper holder, a lower clamper holder which is combined with the upper clamper holder, a clamper which is movably installed between the upper clamper holder and the lower clamper holder and clamps a disc that is disposed on a turntable, a first magnetic member installed between the upper clamper holder and the lower clamper holder, a second magnetic member installed on the turntable to face the first magnetic member so that a magnetic force operates between the first magnetic member and the second magnetic member to clamp the disc and an elastic member disposed between the upper clamper holder and the clamper so as to provide an elastic force to push the clamper against the disc. The disc clamping apparatus clamps discs having various thicknesses. Also, a clamping force of the disc clamping apparatus is changed in proportion to the thickness of the disc, and thus a proper clamping force can be applied to the disc based on the thickness of the disc.

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. A plurality 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: In a disc cartridge and a disc drive apparatus, a disc cartridge has an identification opening where an identification plate is installed to be capable of sliding. A probing portion is installed at the disc drive apparatus and is turned on or off by interference with the identification opening. Thus, the type of a disc can be identified by the on/off actions, that is, by interference with the identification plate and probing portion.

Abstract: A four-axial driving actuator for an optical pickup with improved bobbin dynamic characteristics, in which the winding starting ports for a focus coil, tracking coil, and tilt coil are separate from one another, and the winding end ports thereof are combined as a common ground. The four-axial driving actuator includes: a base; a holder fixed on the base; a bobbin to which an objective lens is fixed; spring wires connected between the bobbin and the holder; and a magnetic driving unit driving the bobbin in the focus, track, or tilt direction with a focus coil, a tracking coil, and a tilt coil, wherein the magnetic driving unit comprises a circuit unit including winding starting ports for the focus coil, tracking coil, and tilt coil, and a common ground port at which winding end ports for the focus coil, tracking coil, and tilt coil are grounded, and the circuit unit applies a voltage to the tracking coil, tracking coil, and tilt coil.