Pioneer Corporation

Eiji Kuroki

Jun Suzuki

Kazutaka Goami

Muneyuki Horiguchi

Katsumi Ishii

A drive device () includes a support (), a first movable portion (), a first magnet (), a second magnet (), a first coil (), and a second coil (). The first movable portion () is swingable in two axial directions with respect to the support (). The first magnet () is positioned inside the first movable portion () when viewed from a first direction. The second magnet () is positioned outside the first movable portion () when viewed from the first direction. Magnetic flux from the first magnet () acts on the first coil (). Magnetic flux from the second magnet () acts on the second coil ().

Drive device and distance measurement apparatus

Provided is an actuator for use in a pickup device, which can improve the quality of the pickup device by reducing a lens distortion even when the frequency of an electromagnetic drive rises beyond a servo band and causes resonance of a lens holder. An adhesive layer () is formed between an outer peripheral portion (A) of an objective lens () and a lens holder (). This adhesive layer () has a sufficient thickness dimension enough to absorb deformation of the lens holder () even when the lens holder () is deformed due to resonance. Even when the frequency at which an electromagnetic drive () operates rises beyond the servo band and causes resonance of the lens holder (), the adhesive layer () functions as a buffer so that deformation of the lens holder () is less transmitted to the objective lens ().

Actuator for use in pickup device in reducing lens distortion

A magnet used for an actuator of an optical pickup has a magnetization pattern has two different pole areas adjacent with each other. At a corner part defined by the boundary line of the two pole areas, the pole area inside the corner part has a projection area, projecting in the direction of the pole area outside the corner part. Owing to the existence of the projection area, insufficiency of the magnetic flux density at the corner part particularly close to the vertex can be improved so that a desirable magnetic field can be provided to the printed coil substrate disposed in the vicinity of the magnet.

Magnet for actuator, actuator, and magnetizing device

The pickup device is used in a drive device of an optical disc and is opposed to the optical disc to irradiate a light beam from a light source onto an information recording surface of the optical disc. The pickup device has the actuator including the objective lens for condensing a light beam on the information recording surface of the optical disc, and irradiation of a light beam on the optical disc is controlled by moving the objective lens. Further, the pickup device has the optical system for directing a light beam, which is emitted from the light source, to a position below the objective lens. The optical system is placed at the same height level as the actuator. Therefore, as compared with the case where the optical system is provided below the actuator, the whole pickup can be smaller in thickness, and it is possible to provide a pickup device suitable for a thin drive device.

Pickup device for optical disk drive

A magnet used for an actuator of an optical pickup has a magnetization pattern with two different pole areas adjacent each other. At a corner part defined by the boundary line of the two pole areas, the pole area inside the corner part has a projection area, projecting in the direction of the pole area outside the corner part. Owing to the existence of the projection area, insufficiency of the magnetic flux density at the corner part particularly close to the vertex can be improved so that a desirable magnetic field can be provided to the printed coil substrate disposed in the vicinity of the magnet.

Actuator for an optical pickup

The actuator is used in a pickup device for a drive device of an optical disc. The actuator is positioned opposing to the optical disc to irradiates a light beam from a light source to an information recording surface of the optical disc. The objective lens is fixed at on the lens holder forming the actuator at a position closer to one end thereof. One coil substrate is fixed on one side face of the lens holder in a range from the one end of the lens holder to a center portion of the lens holder, and the other coil substrate is fixed on the other side face of the lens holder in a range from the other end of the lens holder to the center portion of the lens holder. Therefore, near the end of the lens holder on the objective lens side, the coil substrate is not attached to one side of the lens holder, providing a space below the objective lens. By arranging an optical system to guide the light beam to the objective lens via the space, the optical system can be arranged at the same height level as the actuator.

Actuator

A coil substrate used for a lens driving apparatus is provided in a drive device for an optical disc. The coil substrate includes a tracking coil and a pair of focus coils disposed on a substantially rectangular substrate. The pair of the focus coils is disposed on the both sides of the tracking coil in the direction of the longer side of the substrate. The tracking coil and the focus coils may be substantially aligned in the direction of the longer side of the substrate, or may have the substantially equal lengths in the direction of the shorter side of the substrate. Thereby, the lengths of the coils in the direction of shorter side of the coil substrate can be made smaller. Thus, the coil substrate and the magnet can be reduced in size, and the miniaturization of the entire lens driving apparatus can be achieved.

Lens driving apparatus and coil substrate therefor

A lens driving apparatus for a disk player capable of easily approaching to the innermost circumference of a disk and realizing a reduction in size and weight thereof, in which: an actuator section where a movable portion including printed board coils fixed to the respective side surfaces of a lens holder containing an objective lens is movably supported by outer circumferential side wire-form elastic members and inner circumferential side wire-form elastic members fixed to an actuator base, and a suspension base including a pair of yokes to which a pair of magnets disposed so as to be opposed to each other with a predetermined magnetic space therebetween are fixed and standing portions are included; and a width Wi of each of the inner circumferential side wire-form elastic members is set to be greater than a width Wo of each of the outer circumferential side wire-form elastic members.

Lens driving apparatus for disk player having a lens holder supported by a plurality of elastic members having different spring constants

An apparatus is disclosed for driving a lens for use with a disk player to avoid the swing movement of a movable member without the degradation of the sensitivity of an actuator. The apparatus includes magnetic flux producing elements for providing magnetic flux to tracking coils fixed to a lens holder parallel to a focusing direction. The magnetic flux producing elements provide a first magnetic flux to a first area of the coil and a second magnetic flux to a second area of the coil. The first magnetic flux has a direction opposite to that of the second magnetic flux. At least a portion of a boundary surface between the first and the second areas is inclined from a focus direction of the lens.

Apparatus for driving a lens for use with a disk player

A substrate ( ) and a lens holder ( ) for supporting an objective lens ( ) of the lens driving apparatus are integrally molded by synthetic resin using a predetermined mold. In the case of the integral molding, while long lengths of projection portions ( ) are integrally molded in four corners of the substrate ( ), elastic wires ( ) are buried in the rear ends ( ) of the substrate ( ) and are supported. By filling gaps ( ) defined by the projection portions ( ) and the substrate ( ) by this integral molding with ultraviolet cure resins ( ) to cure the resins, the elastic wires ( ) are buried in the ultraviolet cure resins ( ).

Growing community of inventors

Tokorozawa, Japan

Eiji Kuroki