Abstract: Four filling recesses 14 are formed on an inner peripheral surface of a fitting groove 5, which is formed concentrically with a light passage hole in a holder 3, at intervals of 90 degrees in a circumferential direction. A bottom surface 14a of each filling recess 14 is inclined from one end face 3a of the holder 3 toward a lens receiving seat 6, such that a longitudinal sectional shape of each filling recess 14 is formed in a substantially triangular shape.

Abstract: An objective lens unit has a reinforcing frame portions formed along an outer peripheral surface of each of a pair of tracking coils by applying an epoxy resin adhesive to portions between a lens holder and the outer peripheral surface of each of the tracking coils. Reinforcing core portions are formed by filling the epoxy resin adhesive into a central hole of each of the tracking coils, and a reinforcing connecting portion is formed by filling the epoxy resin adhesive into a gap defined by the lens holder, each of the tracking coils, and a focusing coil.

Abstract: An optical pick-up includes a lens holder and a lens holder supporting portion. The lens holder has a focusing coil, a tracking coil, and a pair of nickel plates arranged to sandwich the focusing coil from the top and the bottom. The lens holder supporting portion includes a pair of permanent magnets having their magnetic poles of the same polarity opposite to each other and sandwiching the lens holder as seen in two dimensions. A sidewall of a slide hole is pressed against a slide shaft. Thus, a disk drive which can suppress a jerky motion of the lens holder when it moves along the slide shaft with a simple mechanism is provided.

Abstract: In a biaxial actuator for an optical pickup, rising pieces are bend-formed on a base member on which a lens holder having an objective lens is placed in such a way as to be able to displace in a focusing direction and in a tracking direction. The strength of the base member is increased by setting the width of the bend-formed portion at the root of each of the rising pieces in such a way as to be larger than the width of any other part of the associated rising piece. Preferably, the shape of a side elevation section of each of the rising pieces is set to be a trapezoid.

Abstract: An objective lens has an actuator base and a lens holder for supporting an objective lens. The lens holder has a shaft hole. A shaft is disposed on the actuator base and fitted to the shaft hole. A cover is attached to the actuator base so as to cover the lens holder in a manner that the cover comes into contact with or comes close to the top face of the shaft. Protrusions are disposed on an actuator base opposing face and a cover opposing face of the lens holder without contacting the shaft. When the protrusions are contacted with the actuator base and the cover, a predetermined gap is formed between the lens holder and the actuator base and between the lens holder and the cover, the gap is communicated with a space in the cover through the side of the protrusions.

Abstract: An objective lens unit has a reinforcing frame portions formed along an outer peripheral surface of each of a pair of tracking coils by applying an epoxy resin adhesive to portions between a lens holder and the outer peripheral surface of each of the tracking coils. Reinforcing core portions are formed by filling the epoxy resin adhesive into a central hole of each of the tracking coils, and a reinforcing connecting portion is formed by filling the epoxy resin adhesive into a gap defined by the lens holder, each of the tracking coils, and a focusing coil.

Abstract: An optical pickup in which a substantially L-shaped retaining seat having an inclined side surface and an inclined end surface which are orthogonal to each other is formed on one side surface of a light passage hole formed in a housing, a groove is formed between the inclined side surface and the inclined end surface, while a positioning seat is formed on the other side surface of the light passage hole. An adhesive agent is injected between each of both end portions of a half mirror, which is disposed in an inclined state on the both seats, and each of the seats and into the groove. The width of an opening portion of the groove is set to be larger than the width of an depth portion of the groove.

Abstract: An actuator for an optical pickup apparatus includes an actuator base member having a pair of yoke portions rising up from a base portion as well as a pair of magnets respectively secured to inner side surfaces of the yoke portions, a yoke member having a pair of yokes rising up from a baseplate portion. The yokes are respectively inserted in a pair of insertion holes of the base portion, and the baseplate portion is superposed on the base portion. The yokes are bonded to the base portion by an adhesive, and the baseplate portion is secured to the base portion by a fixing member.