Hitachi Media Electronics Co., Ltd.

Souichirou Yamada

Katsuhiko Kimura

Manabu Ochi

Takahiro Yamaguchi

Tetsuo Itou

Jun Hato

Yasushi Kinoshita

Yoshihiro Satou

Atsushi Kazama

Yoshitaka Kusano

Takeshi Oikawa

In the object lens drive unit including a lens holder with an object lens attached to, a plurality of driving coils attached to the lens holder, connection substrates attached to both sides of the lens holder, and a plurality of suspension wires with end parts thereof connected to the connection substrates for operatively supporting the lens holder, a plurality of sets of wire connection electrodes for connecting the suspension wires and coil connection electrodes electrically connected to the wire connection electrodes for connecting terminal wires of the coils are arranged in line in an optic axis direction of the object lens and the wire connection electrodes and the coil connection electrodes are formed in a symmetric shape to a central axis parallel to the optic axis direction on the connection substrates.

Object lens drive unit and optical pickup using the same

An optical pickup has a laser light source, beam splitter, collimator lens, reflection mirror, objective lens and photo detector are mounted in a case. An objective lens actuator includes a magnetic member and magnet. The optical pickup may become contaminated by uncured adhesive remaining at the edges of the adhesive surfaces of the magnet and the magnetic member that is transferred to the optical pickup via finger cots or tweezers, etc. In an adhesion step between the magnet and the magnetic member, in which part of a groove near to the center of the surface has a small depth and part of the groove near to the outer circumference of the surface has a large depth, an adhesive is drawn toward the center of the surface of the magnetic member by a capillary phenomenon and is prevented from spreading along the outer edge of the surface.

Optical pickup

In an optical pickup for use in an optical disc device, wire rods are wound directly around a lens-coil holder to make tracking coils and focus coils. The lens-coil holder is divided into three holders, one of which holds an optical lens thereon and has on its sides wire-winding protrusions for wiring wire rods therearound to make tracking coils. The remaining holders have focus coils that are wound therearound. Alternatively, the lens-coil holder is divided into two holders, one of which has on its sides wire-winding protrusions for wiring wire rods therearound to make tracking coils. The remaining holder holds an optical lens thereon and has focus coils that are wound therearound. The lens-coil holder has a cavity for letting pass through a laser beam emitted in parallel to an optical disc surface.

The present invention provides an object lens actuator in which a tilt of an object lens due to a change of an ambient temperature is inhibited even when a metal member is attached to a resin based securing part. It is desirable to improve quality of writing and playing in a disc drive using the object lens actuator. This is achieved by coupling a metal member having a flat portion and bent portions to a securing part near top ends of the bent portions. The flat portion has a normal in the focusing direction. The bent portions extend in the focusing direction from the respective ends of the flat portion in the tracking direction. The securing part has an opening therethrough in the focusing direction, and in the opening, the metal member and the securing part may be coupled between each outermost two support members in the focusing direction.

Object lens actuator and disc drive using the same

An objective lens actuator in an optical pickup, having a semiconductor laser diode, electro-optic parts, such as a lens or the like, as well as, the objective lens actuator, etc., in a case, comprises: a holder, which mounts an objective lens and a coil thereon, as being a movable part; a magnetic circuit part, which is made up with a magnet for magnetically driving said holder and a yoke; a plural number of elastic support parts which elastically supports said holder; and a support part, which supports other ends of said elastic support parts, wherein said support part has a part, which is cut open in parallel with the elastic support parts, between said elastic support parts, and has a through hole, in which said elastic support part passes through for each of said elastic support parts, and thereby to provide the objective lens actuator for lowering the unwanted vibration mode of the objective lens, and also enabling a stable control thereof.

Optical pickup with support part having hole for being inserted with a projection part of a case

An objective lens actuator which drives an objective lens in a focusing direction and a tracking direction, so as to focus lights on a recording surface of an optical disc, as a recording medium of information. The objective lens actuator includes a magnet, a lens holder which is configured to hold the objective lens thereon, and four pieces of tracking coils which are disposed in a line on a side surface of the lens holder for holding the objective lens thereon, facing to the magnet.

Growing community of inventors

Yokohama, Japan

Souichirou Yamada