Abstract: In an optical pickup for an optical disk device using BD, DVD and CD as recording media, simplification of constitutional elements is promoted. The optical pickup includes a dual wavelength type laser beam source generating laser beams for DVD and CD, a single wavelength type laser beam source generating a laser beam for BD, and a first wave plate converting the laser beam for BD generated from the laser beam source concerned into circular polarization. It further includes a second wave plate converting the laser beam for DVD generated from the dual wavelength type laser beam source into 45-degree linear polarization. Favorable recording and reproduction are performed by radiating the laser beam to the recording medium concerned as the circular polarization for BD and the 45-degree linear polarization for DVD.

Abstract: An optical head capable of recording or playing back optical discs is provided. The optical disc comprises a light source to emit a beam, an objective to focus the beam on an optical disc, a beam dividing element having a plurality of divided areas with which to divide a cross section of the beam reflected from the optical disc, and a light detector to receive the beams divided by the beam dividing element, wherein the beam dividing element has in at least one of the plurality of areas an aberration imparting function of imparting an astigmatism or defocus aberration to a beam passing through that area.

Abstract: An optical pickup which excels in assembly workability and which can increase the drive force generated in a focusing coil is provided. The optical pickup has an objective lens, a lens holder holding the objective lens, and a first and a second focusing coil wound around the lens holder. The first focusing coil includes an upper part wound about a central axis extending in parallel with an optical axis of the objective lens and a lower part connected to the upper part. The second focusing coil includes an upper part wound, in a wiring system separate from the first focusing coil, about a central axis extending in parallel with the optical axis of the objective lens and a lower part connected to the upper part.

Abstract: Disclosed is an optical information reproducing apparatus that has a light path difference between two lights easily adjusted, has a high effect on the amplification of a signal, and detects an optical information signal of an interfering type. The optical information reproducing apparatus splits a luminous flux emitted from a laser source into a first luminous flux as a signal light and a second luminous flux as a reference light not collected on an optical information recoding medium, makes the signal light optically interfere with the reference light in a state in which the signal light and the reference light are different from each other in a phase relationship to thereby produce interfering lights, and detects the interfering lights.

Abstract: When an optical pickup used for an optical disk device is formed, the optical pickup includes a stepping motor which drives a lens used to correct for spherical aberration, and the stepping motor is mounted in such a manner that the stepping motor is exposed at a surface (upper part) where the stepping motor faces the optical disk. In addition, the stepping motor is mounted in such a manner that the stepping motor is exposed at a surface (lower part) opposite the surface where the stepping motor faces the optical disk. Consequently, the optical pickup used for an optical disk device is adapted to cool a built-in stepping motor without using expensive components when the optical pickup is formed, the optical pickup being configured to make the optical pickup itself thinner and making the operation of the stepping motor stable.

Abstract: When an optical pickup used an optical disk device is formed, a PWB (Printed Wiring Board) which serves as a top cover is used at at least a part of a surface of a housing which houses the optical pickup, the surface facing an optical disk. The PWB (Printed Wiring Board) is adapted to seal components inside the optical pickup, and to reduce the flexure of FPC (Flexible Printed Circuits). Moreover, the printed wiring board is provided with a connector which allows the connection of FPC for connection to circuits outside the optical pickup. Consequently, the slack of the FPC can be eliminated, and optical members provided inside the optical pickup can be protected without using a metal cover.

Abstract: An optical pickup device including: a laser diode for emitting laser light; an objective lens which irradiates an optical beam emitted from the laser diode; an actuator which displaces the objective lens in a radius direction of the optical disc; a grating for branches an optical beam reflected by an information recording layer into plural regions; and one photodetector having plural light receiving parts for receiving the branched optical beams, wherein the photodetector has a first light receiving part which detects zero-th order grating diffracted light and plural second light receiving parts which detecting grating diffracted light having an order not less than that of ±first order grating diffracted light; a detected signal of the zero-th order grating diffracted light is defined as a reproduction signal; and a detected signal of the grating diffracted light is defined as a signal for servo controlling.

Abstract: An optical pickup includes a light source, an objective lens, a diffraction grating that divides an optical beam reflected from a predetermined information layer, into a plurality of optical beams, and a detector having a plurality of photo-receivers to receive a plurality of optical beams. The diffraction grating has a predetermined region for dividing from a signal light beam a region including a central portion of a spot which the signal light beam will form on the diffraction grating. A distance from a central section of the detector to that of a spot center photo-receiver on the detector, the spot center photo-receiver being provided to receive the optical beams formed by division in a predetermined region of the diffraction grating, is equal to or greater than a spot radius of the unwanted light beams entering the predetermined region of the diffraction grating, on the detector.

Abstract: The invention provides an optical pickup device that ensures complete curing of adhesive when a tilt adjusting holder is glued to an objective lens holder. The optical pickup device comprises: a light source; an objective lens for focusing light emitted from the light source onto an optical storage medium; a tilt adjusting holder to which to secure the objective lens; and an objective lens holder to which to glue the tilt adjusting holder. The objective lens holder includes: adhesive joint sections for securing the tilt adjusting holder to the objective lens holder using an adhesive; a seat section on which the tilt adjusting holder abuts; and adhesive anti-overflow pockets, located between the adhesive joint sections and the seat section, for receiving the adhesive when the adhesive flows from the adhesive joint sections.

Abstract: Disclosed is an optical information reproducing apparatus that has a light path difference between two lights easily adjusted, has a high effect on the amplification of a signal, and detects an optical information signal of an interfering type. The optical information reproducing apparatus splits a luminous flux emitted from a laser source into a first luminous flux as a signal light and a second luminous flux as a reference light not collected on an optical information recoding medium, makes the signal light optically interfere with the reference light in a state in which the signal light and the reference light are different from each other in a phase relationship to thereby produce interfering lights, and detects the interfering lights.

Abstract: An optical pickup includes a light source, an optical system for irradiating a recording medium including a plurality of recording layers with light from the light source, a diffraction optical element that divides light reflected from the recording medium into a plurality of optical fluxes and diffracts the fluxes, and an optical detector receiving the optical flux diffracted by the diffraction optical element. The optical detector includes a light receiving element detecting a focus error signal, wherein a longitudinal direction of the light receiving element is arranged to coincide with a circumferential direction of the recording medium, or arranged to be inclined to a circumferential or radial direction.

Abstract: To provide an optical pickup device adapted such that for adhesion fixing of a holder for holding an LD or a light-receiving element to an optical pickup casing via an ultraviolet-curable adhesive, curing shrinkage during ultraviolet irradiation can be reduced and adhesion fixing achieved with high positioning accuracy. In a structure for adhesion fixing of a holder for holding an LD or a light-receiving element to an optical pickup casing via an ultraviolet-curable adhesive, since protrusions are provided at peripheral sections (UV irradiation light source side) on a bonding surface of the holder, a section exposed to strong UV light is first cured, then after the adhesive has moved from an uncured section, the amount of shrinkage of the first cured section in a Z-direction is reduced, and the uncured section is cured.

Abstract: An optical pickup includes a light source, an objective lens, a diffraction grating that divides an optical beam reflected from a predetermined information layer, into a plurality of optical beams, and a detector having a plurality of photo-receivers to receive a plurality of optical beams. The diffraction grating has a predetermined region for dividing from a signal light beam a region including a central portion of a spot which the signal light beam will form on the diffraction grating. A distance from a central section of the detector to that of a spot center photo-receiver on the detector, the spot center photo-receiver being provided to receive the optical beams formed by division in a predetermined region of the diffraction grating, is equal to or greater than a spot radius of the unwanted light beams entering the predetermined region of the diffraction grating, on the detector.

Abstract: 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.

Abstract: To provide a reliable optical pickup device, a pickup case and an optical component including a lens are fixed by laser welding to increase the welding strength and reduce the positional displacement due to environmental changes. In a laser welded portion between a pickup case and an optical component including a lens, the optical component is provided with a joint portion having a convex protrusion at a portion to be joined to the pickup case. Laser beam irradiation is performed extending longer than the protrusion to form a thick welded portion at an end of the protrusion, in order to increase welding strength between the optical component and the pickup case.

Abstract: A connection structure of Flexible printed circuits comprising: first and second Flexible printed circuits, respectively, including a base formed of a resin, a plurality of wiring patterns arranged side by side on the base, a cover film formed of a resin to cover opposite sides of the wiring patterns to the base, and a connection portion in which the plurality of wiring patterns are not covered by the cover film, the connection portions of the first and second Flexible printed circuits being connected with each other. The wiring patterns in the connection portions include a large width portion which is larger in width than the wiring patterns covered by the cover film. The large width portions on the first Flexible printed circuit and the large width portions on the second Flexible printed circuit are connected to each other by means of soldering.

Abstract: An optical pickup includes an objective lens, a lens holder which holds the objective lens, a focusing coil attached to the lens holder having the winding axis directed at the optical axis of the objective lens, and a magnet provided opposite the side surface of the lens holder. A protruding portion is attached to the side surface of the lens holder at a side apart from the objective lens with respect to the optical axis direction of the objective lens farther than the focusing coil.

Abstract: 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.

Abstract: An optical pickup includes an object lens; a moving part including the object lens and coils; rod-shaped support members disposed in a focusing direction, one end of each of the support members being attached to side surfaces of the moving part in a tracking direction; a fixing part for fixing the other end of each of the support members; a yoke including magnets; and gel holding parts, each of the gel holding parts including walls on both sides of the support members in the tracking direction, and the support members being disposed on both sides of the moving part in the tracking direction. Each of the gel holding parts includes an opening at one end on an optical disc side in the focusing direction and includes a cutout in the wall farther from the object lens in the tracking direction, the cutout extending from an edge of the opening.

Abstract: An objective lens actuator 25, for driving an objective lens 1 for focusing lights upon a recoding surface of an optical disc, comprises a moving part 2, which comprises the objective lens 1 and a coil; a magnet, which is fixed on a yoke and drives the moving part 2; a plural number of elastic support parts, each of which supports the moving part 2 at an end thereof; a first fixing portion 5a and a second fixing portion 5b, which fix other ends of the plural number of elastic support parts 4 and are disposed opposite to each other in a focus direction; and a moving mechanism 6, which is provided on the first and second fixing portion 5a and 5b, so that the first and second fixing portions 5a and 5b can move in the focus direction, relatively, and thereby providing the objective lens actuator 25 enabling to reduce the dynamic relative tilt between the optical disc and the objective lens 1 (i.e.