Abstract: A method and apparatus for managing a defective area on a optical recording medium, e.g., of writable once type, permits more efficient writing and management of defect list information or temporary defect list information for managing the defective area in a minimum recording size. The method includes writing data in a defective area existing on a high density optical disc, e.g., such as a BD-WO, in a spare area in place of the defective area, producing defect list information for access to the data replacement written in the spare area and writing in a particular area for defect management. The defect entries actually corresponding to the replacement written data, and writing location information of the next available spare area are written and managed as defect list information for management, or the writing location information of a location where replacement writing is possible is written and managed as defect definition structure information.

Abstract: A main pole layer is deposited within an opening in a patterned photoresist layer on a substrate. The photoresist is thinned to expose an upper portion of a pole tip region that is then trimmed to a rectangular shape while a lower portion retains an inverted trapezoidal shape. Thereafter, a second trimming process forms a pole tip with a first width in the upper rectangular portion and a second thickness and second width which is less than the first width in the lower portion. A CMP step subsequently thins the upper portion to a first thickness of 0.04 to 0.08 microns while the second thickness remains at 0.16 to 0.32 microns. The bottom surface of the lower portion along the ABS becomes the trailing edge in a recording operation. The pole tip has a consistent first width (track width) that is not influenced by CMP process variations.

Abstract: A disk-chucking device comprises a pressing member including a circular groove which is provided around a circumference of the clamp member, and a clamping member mounted on a turning plate for clasping the circular groove of the pressing member. The turning plate provides a through hole at the center thereof which allows the pressing member passing through, and a plurality of first notch portions disposed along the circumference of the through hole. The turning plate is slidably connected to a mounting board through the clamping member. The turning plate can rotate with respect to the mounting board to move the pressing member vertically. Thus, the pressing member can be pressed onto and removed from a disk support of the displayer according to the rotation of the turning plate. The present disk-chucking device can chuck the disk securely regardless of the position of the disk player.

Abstract: A device for reading from or writing to optical recording media having an optical assembly and a laser diode coupled thereto is described. The laser diode is a twin laser diode which is coupled to the optical assembly by means of a translationally displaceable rotary joint.

Abstract: A disk drive includes a housing including a support post extending from the housing. The support post defines a post axis. The disk drive further includes an actuator rotatably coupled to the housing. The disk drive further includes a VCM top plate physically coupled to the housing and comprising a ferromagnetic metal. The disk drive further includes a VCM magnet magnetically coupled to the VCM top plate. The disk drive further includes an actuator latch contactable with the actuator. The latch includes a post opening. The latch is pivotably mounted about the support post with the support post disposed in the post opening. The disk drive further includes a pivot ball disposed in the post opening and partially protruding from the latch between the VCM top plate and the latch along the post axis.

Abstract: Disclosed are an apparatus and a method for controlling a tracking servo in a near field optics. Gap error signals are detected in a divided state, and a push pull signal is compensated based on the detected gap error signals. A photo detector detecting the gap error signals is divided into two areas such that movement of an image formed on the photo detector can be detected. The push pull signal is compensated by subtracting a value proportional to a difference value between the two gap error signals detected in the photo detector. The difference value between the two gap error signals is proportional to a dc offset component included in the push pull signal. Accordingly, it is possible to simply remove a dc offset included in a push pull signal without largely modifying the near field optics, so that it is possible to exactly perform a tracking servo operation.

Abstract: An optical pickup actuator includes a lens holder on which tracking and focusing coils are attached, at least one of the coils being a polygon coil having at least two sides that are different in a length from each other, magnets disposed facing the coils, and a rotation preventing unit formed on the lens holder. The rotation preventing unit surface-contacts an inner surface of the polygon coil to prevent the polygon coil from being twisted.

Abstract: A magneto-resistive element has: a first stacked film assembly having a pinned layer, a spacer layer, and a free layer; a first electrode layer which is arranged such that the first layer is in contact with the first electrode layer on the other side of the first layer, the first electrode layer being made of a ferromagnetic material; and a second electrode layer which is arranged on a side that is opposite to the first electrode layer with regard to the first stacked film assembly. The first and second electrode layers are adapted to apply a sense current to the first stacked film assembly and the first layer in a direction that is perpendicular to layer surfaces. The first layer is made of gold, silver, copper, ruthenium, rhodium, iridium, chromium or platinum, or an alloy thereof.

Abstract: The aspects of the present invention provide a device for tracking, a method for tracking, and a method for building the device for tracking the location of a media cartridge. The device includes a first antenna connected to a media unit. The device also includes a second antenna connected to the media unit, wherein the second antenna has a range that is longer than the first antenna. The device also includes a switch, wherein the switch allows the media cartridge to operate in a first mode and a second mode, wherein in the first mode the first antenna is operable, and wherein in the second mode the second antenna is operable.

Abstract: The present invention discloses an optical disk drive comprising a traverse, a traverse frame, a chassis and a stopper. The traverse frame is disposed on the chassis. And one end of the traverse is disposed on the chassis and the other end is disposed on the traverse frame. The stopper includes a protruded arm and an extended arm extended from the protruded arm. The protruded arm is integrated with the traverse by sheet metal forming and the extended arm is disposed above the traverse frame. The extended arm of the stopper is interfered with the traverse frame when a heavy shock is applied to the optical disk drive. Therefore, the optical disk drive including the stopper can prevent the separation between the traverse and the traverse frame without screws when a sudden hit is applied thereto.

Abstract: A head support device of self-balancing type and a disk drive are disclosed. The head support device reduces manufacturing variation in a load and the number of components, and has stability and reliability, while being inexpensive. In this head support device, a flange and a nut cramp, via a collar, a head support arm having a reinforcing plate fixed thereto. The head support arm is supported rotatably about a line provided between contact points at which pivots contact the flange and in a direction perpendicular to a recording medium. A spring as an elastic member provides an urging force toward the recording medium, and is provided unitarily with the head support arm. Bent portions are provided on both sides of the arm composing the head support arm to a tab.

Abstract: When “buffer under run” (BUR) occurs during recording of a visible image on an optical disk, recording operation is interrupted. As in the case of type A, when BUR1 occurs after data have been transferred through an integral multiple of one revolution, data are recorded continuously from a reference angle position without host device discarding data. As in the case of type B, when BUR2 occurs after data have been transferred in a value which is other than the integral multiple of one revolution, data corresponding to a duration from the position where BUR occurs to the start of the next revolution are discarded, data are continuously recorded from the reference angle position. Thereby, rendering can be spliced in a visually-smooth manner.

Abstract: A recording disk cartridge includes a plurality of flexible recording disk media, a rotational member, and a cartridge case. The rotational member holds the recording disk media so that the recording disk media simultaneously rotate. The cartridge case provides a rotationally free housing for the recording disk media and the rotational member. The cartridge case has an opening to allow an end portion of the rotational member to be exposed to an outside of the cartridge case. The recording disk cartridge has an elastic member which provides a force to thrust the rotational member toward the opening.

Abstract: A pickup supporter 72 supporting a pickup device 70A includes a driver 76 having an abutting surface 764 that is a flat surface substantially in parallel to an axial direction of a lead screw 752 and intersecting with both a focus direction and a plane direction substantially vertical to the focus direction. With such arrangement, even when a posture of the pickup supporter 72 is changed by adjusting heights of the main shaft 74A and the sub shaft 74B, the screw abutting surface 764 can abut on the lead screw 752 at a substantially constant angle. Therefore, when the posture of the pickup supporter 72 is changed, substantially constant driving force can be transmitted from the lead screw 752, so that stable and proper driving force can be constantly obtained.

Abstract: A magnetic head structure for use in perpendicular magnetic recording. The magnetic head includes a magnetic write head having a return pole with a magnetic shunt structure extending from the back end opposite the ABS. The magnetic shunt structure prevents magnetic field from the write coil from reaching and affecting the read head. More specifically the shunt structure prevents magnetic field from the portion of the write coil beyond the back gap (as measured from the ABS) from magnetizing a magnetic shield of the read head. The shunt structure is also configured so as to avoid stray field writing. The size and shape of the shunt structure is therefore, limited to avoid attracting stray fields that might cause such stray field writing.

Abstract: In one illustrative example, a three terminal magnetic sensor (TTM) suitable for use in a magnetic head has a sensor stack structure which includes a base region, a collector region, and an emitter region. A first barrier layer separates the emitter region from the base region, and a second barrier layer separates the collector region from the base region. A plurality of terminals of the TTM include a base lead coupled to the base region, a collector lead coupled to the collector region, and an emitter lead coupled to the emitter region. Preferably, the base region consists of a free layer structure so as to have a relatively small thickness. A pinned layer structure is made part of the emitter region. An in-stack longitudinal biasing layer (LBL) structure is formed in stack with the sensor stack structure and has a magnetic moment that is parallel to a sensing plane of the TTM for magnetically biasing the free layer structure.

Abstract: A robotic unit with a picker (18) serves for handling data media in a storage device. The robotic unit can be traversed with a base plate (24) on a guide bar (16). On the base plate (24) a rotary plate (28) is disposed which can be turned about a vertical axis. On the rotary plate (28) two motors (52, 56) are disposed, each of which causes, via a toothed wheel drive, the translational and the turning movement of the robotic unit. The toothed wheel drives (48, 50, 54, 58) are disposed in a common plane in an indented recess (46) of the base plate (24).

Abstract: In one illustrative example, a three terminal magnetic sensor (TTM) has a sensor stack structure which includes a base region, a collector region, and an emitter region. A first barrier layer is located between the emitter region and the base region, and a second barrier layer is located between the collector region and the base region. A plurality of terminals of the TTM include a base lead coupled to the base region, a collector lead coupled to the collector region, and an emitter lead coupled to the emitter region. The collector region is or includes a layer of semiconductor material. The base region includes a free layer structure. The TTM further includes a self-pinned layer structure and an in-stack longitudinal biasing layer (LBL) structure formed in stack with the sensor stack structure, with a magnetic moment that is parallel to a sensing plane of the TTM for magnetically biasing the free layer structure.

Abstract: Reproduced signals are equalized by the least square technique by using a predetermined number of data samples binarized by a Viterbi decoder. Even when data written on an optical disk is unknown, the data can be equalized in a stable manner and can be reproduced at a low error rate without instability factors such as divergence due to interference.

Abstract: A disk drive includes a disk drive base and an actuator that is rotatably coupled to the disk drive base. The actuator has an axis of rotation. The disk drive further includes a latch. The latch includes a fixed portion that is firmly coupled to the disk drive base, and a latching portion. The latch further includes a latch arm portion connecting the latching portion to the fixed portion. The latch arm portion includes a hinge region. The latch arm portion is thinner in a direction normal to the axis of rotation in the hinge region than the latch arm portion is outside of the hinge region. The latch arm portion, the latching portion, and the fixed portion are a single component having material continuity rather than an assembly of sub-components.