Abstract: An objective lens actuator includes an objective-lens-side main magnet and two stationary-holder-side main magnets mounted to a base body. The objective-lens-side main magnet is positioned to face the two stationary-holder-side main magnets across a gap. The magnets form a magnetic circuit producing magnetic flux extending from either the objective-lens-side main magnet or the two stationary-holder-side main magnets to the remaining magnet(s). The objective lens holder includes a focusing coil and a tilting coil. The focusing coil is located so that the objective-lens-side main magnet and the two stationary-holder-side main magnets are present outside and inside a winding of the focusing coil respectively. The tilting coil is located so that: the objective-lens-side main magnet is present outside a winding of the tilting coil; one of the stationary-holder-side main magnets is present inside the winding; and the remaining one of the stationary-holder-side main magnets is present outside the winding.

Abstract: An objective lens driving apparatus used with an optical pickup includes a base, a holder provided on the base, a blade on which an objective lens is mounted, an elastic support body elastically supporting the blade and which is capable of moving with respect to the holder, a pair of magnetic members installed on the base to face each other, and a coil assembly including a focus coil, a tracking coil, and a tilt coil, the coil assembly being installed at the blade so as to be disposed between the magnetic members. Thus, coils needed to change the position of an objective lens are incorporated into a single coil assembly and are arranged between a pair of magnets, and an installation space is small so that the apparatus can be made compact.

Abstract: An actuator includes an intervention member being interposed between an object lens and a bobbin for supporting the object lens and different from the bobbin in thermal conductivity, thereby preventing an occurrence of degradation of the lens characteristic of the object lens caused by unevenness of the temperature distribution in the object lens due to the heat generated by a coil.

Abstract: An optical type pick-up actuator can include a lens holder having an object lens for condensing a light on an optical disc mounted at one side thereof and activated in a predetermined direction, and a plurality of yokes and magnets facing one another. A focusing coil and a tracking coil can be installed between the plurality of magnets, and disposed in a Y-axis direction to activate the lens holder by an electromagnetic force with the magnets in focusing and tracking directions.

Abstract: An optical pickup apparatus includes an object lens opposed to a disk, a fixing section, and a bobbin suspended by the fixing section and four or more longitudinal elastic members for supporting the object lens. A plurality of coil pairs symmetric with respect to a point (180 degrees), the centroid of the object lens placement face of the bobbin exist and are placed in a different surface.

Abstract: An optical pickup actuator, an optical pickup employing the optical pickup actuator, and an optical disc drive apparatus employing the optical pickup. The optical pickup actuator includes a blade on which an objective lens for condensing light onto an optical disc is mounted, and on which coils are wound, and a base which includes a plurality of driving magnets, which interact with current flowing through the coils, to generate force that drives the blade in a predetermined direction and a shielding magnet, which is arranged opposite to and has the same polarity as at least one of the driving magnets, to block leakage magnetic flux from the driving magnets.

Abstract: An objective-lens driving apparatus includes permanent magnets on both ends of the movable unit, simultaneously, on the other side of the movable unit parallel to the tracking direction, also a permanent magnet at a position closer to the center of the movable unit. This configuration makes it possible to reduce each moment generated at each of a focusing coil and a tracking coil when an objective lens is displaced.

Abstract: An optical pickup actuator for driving, by a magnetic driving unit, in a focusing direction, a tracking direction, and a tilting direction, a bobbin on which an objective lens is disposed and which is movably supported by suspension wires, including at least one damping member is disposed at a position where greatest changes in the optical pickup actuator occur when driving the bobbin in the focusing direction, the tracking direction, and the tilting direction, so that a size of a second resonant peak is reduced.