Abstract: To reduce vibrations occurring in an objective lens driving apparatus there is provided an objective lens driving apparatus used in an optical pickup that reads/writes information from or onto an optical disk using an objective lens. The objective lens driving apparatus has a lens holder that holds an objective lens in a center part thereof, and a plurality of tracking coils that are disposed on both sides of the lens holder. The mass of a pair of first tracking coils that are disposed on one of the sides is greater than the mass of a pair of second tracking coils that are disposed on the other side.

Abstract: An information recording medium is provided, which includes a plurality of recording layers and a first disc information area for storing parameters relating to access to the plurality of recording layers and formats relating to the plurality of recording layers. The first disc information area is provided in a first recording layer which is one of the plurality of recording layers.

Abstract: A data storage cartridge comprises data storage media configured to store data for read and/or write access, wherein the data may be arranged in a plurality of partitions; and a plurality of cartridge memories. Each cartridge memory comprises a communication interface and a memory, wherein the information of the memory is formatted to allow association with at least one of the plurality of partitions of the data storage media. Thus, each of the cartridge memories may have a separate user and provide access for that user to a separate partition or subset of partitions.

Abstract: An active noise canceller outputs a noise pattern learning request signal to a hard disk drive causing the hard disk drive to perform a predetermined operation, receives noise at this moment through a sound-receiving unit, and stores, in a nonvolatile memory unit, a relationship between the noise and a head operation data signal output from the hard disk drive. Based on the operation data signal outputted from the hard disk drive, the active noise canceller generates a noise-canceling sound while making a reference to the above relationship stored in the nonvolatile memory unit. Therefore, the signal processing needs a low degree of response for operating the noise-canceling sound.

Abstract: An apparatus for controlling a monitor photo diode (PD) of an optical pickup system monitors an optical power signal output for writing data on or reading data from a disk. The apparatus includes a comparator which compares a voltage signal corresponding to the optical power signal output from the LD with a predetermined reference voltage signal, and a gain selector which selectively issues a gain output from the comparator depending on the type of the optical power signal output from the LD.

Abstract: Disclosed is a rotating media storage device (RMSD) that has at least one calibration track with unique calibration servo synch marks (SSMcs). The RMSD includes a disk that comprises a plurality of tracks including a calibration track having a plurality of normal servo wedges distributed around the calibration track. At least one of the normal servo wedges includes a normal servo synch mark (SSMN). Further, at least one calibration servo wedge is distributed between a pair of normal servo wedges. The calibration servo wedge includes a calibration servo synch mark (SSMC). The calibration SSMC includes a pattern that is different than the pattern associated with the normal SSMN.

Abstract: The present invention relates to a device for reading from and/or writing to optical recording media (1) having an optical scanner (2) for scanning the recording medium (1) by means of a light beam (3) and for generating scanning signals (HF) from the reflected beam (3), a data slicer (5) for converting a scanning signal (HF) output by the optical scanner (2) into a binary signal (HF?), an averaging unit (6) for forming an average value (M) from the scanning signal (HF, HF?) as input signal of the data slicer (5), and a control unit (14) for changing a parameter (T, OF) of the averaging unit (6). The object of the present invention is to propose a device of this type and also a suitable method therefor in which the average value (M) can be adapted to disturbances during the scanning of the recording medium.

Abstract: It is an object of the invention to provide an aberration correcting mirror which has a small size, power saving, a low voltage, a low price and high precision. In particular, it is an object to provide a practical mirror for correcting a spherical aberration.

Abstract: An optical pickup device includes a light source emitting a light beam having a wavelength within a range of 390 nm to 420 nm and an optical element to perform recording and/or reproducing of information of an optical disk having a protective substrate thickness d1 mm using the first light beam from the first light source, wherein the optical element is made of a mixed material produced by dispersing particles into a resin, a sign of a refractive index change ?n2/?t of the particles owing to a temperature change is opposite to a sign of a refractive index change ?n1/?t of the resin owing to a temperature change, or an absolute value of the refractive index change ?n2/?t is smaller than an absolute value of the refractive index change ?n1/?t.

Abstract: Disclosed is an optical pickup including a polarization holographic optical element (HOE) and a photodetector. The optical pickup includes a light source, an optical path changer, an objective lens, a polarization HOE, and a photodetector. The polarization HOE has a pattern designed to generate different astigmatisms in the left and right halves of the polarization HOE in a tangential direction and to divide plus and minus first-order beams in a radial direction. The photodetector includes a first light-receiving portion receiving a zero-order beam and second and third light-receiving portion that are disposed on either side of the first light-receiving portion in the tangential direction and respectively receive the plus and minus first-order beams.

Abstract: A disk drive is disclosed comprising an actuator arm, a head attached to a distal end of the actuator arm, a voice coil motor for rotating the actuator arm about a pivot, and an optical sensor operable to generate a first position signal representing a position of the actuator arm with respect to the disk, wherein the first position signal is substantially unaffected by a vibration mode of the actuator arm. Servo sectors recorded on the disk are processed to generate a second position signal representing a position of the head with respect to the disk, wherein the second position signal comprises a significant component due to the vibration mode of the actuator arm. A control signal is applied to the voice coil motor in response to the first and second position signals.

Abstract: A recording/reproducing apparatus includes a cartridge holder which is rotatably provided on a chassis, into which a disc cartridge enclosing a magneto-optical disc is inserted, and which holds the inserted disc cartridge, an optical pickup that irradiates laser light onto the magneto-optical disc, a magnetic head that is provided on the upper surface side of the cartridge holder facing the optical pickup and that is moved between a lowered position close to the optical disc and a raised position away from the magneto-optical disc, at least one first sliding member that is movably provided on the cartridge holder, a head raising/lowering mechanism that moves the magnetic head between the upper position and the lower position by moving the first sliding member, and a driving mechanism that is disposed on a lower surface side of the chassis, engages the sliding member, and moves the first sliding member.

Abstract: A combined signal Spc in which a pre-pit signal is superposed on a wobble signal is generated based on a radial push-pull signal Spp with a noise component having been removed therefrom. Based on the combined signal Spc, a wobble signal SWB with the phase ?0 not having time fluctuation and a pre-pit signal SPD are generated with the phases compared to each other, and then a phase adjustment signal SCNT corresponding to a phase difference ?e is generated. The phase differences ?e are stored, and an average value ?r thereof generated, the phase difference ?e is compared to the average value ?r, the phase ?0 is shifted according to only by the phase difference ?e only when the phase difference ?e is within the range of (?r±W), and then a wobble signal SWB with the phase ?1 synchronized to the pre-pit signal SPD is generated.

Abstract: Congested rewriting in the same area is to be evaded to suppress the tendency towards occurrence of defective areas. When a stream 1 has been recorded, the last written address, representing the last written position, is stored. When recording a stream 2 next, recording is started directly following the position indicated by the last written address for the stream 1. The last written address, corresponding to the last address of the recording position, is stored. If the stream 2 is erased for recording a stream 3, recording is started not at a position directly following the last written address of the stream 1, but from a position directly following the last written address of the stream 2. When the stream 3 has reached the end of a recording area, the next following data is recorded as from a position directly following the stream 1.

Abstract: An image forming apparatus includes: a spindle motor (130) for rotating an optical disk (200); an optical pick-up (100) for applying laser light to the optical disk which moves in a radial direction of the optical disk; a stepping motor (140) for transporting the optical pick-up in the radial direction by a predetermined distance every time the optical disk is rotated plural times; a tracking actuator for actuating a position of laser light irradiated from the optical pick-up; a servo circuit (138) for controlling the tracking actuator in such a manner that irradiation loci of the laser light is made different from each other every time the optical disk is rotated plural times; and a data converter (160) for defining intensity of the laser light in accordance with gradation of dots to be arrayed and a total rotation time of the optical disk.

Abstract: A disk drive includes a rotatable storage disk, an actuator motor, a slider that magnetically interacts with the storage disk, and a drive circuitry. A portion of the slider moves between a first position wherein the slider does not contact the storage disk and a second position wherein the slider contacts the storage disk. The drive circuitry can detect when the position of the slider changes between these positions. In one embodiment, the drive circuitry monitors off-track movement of the slider to detect when the slider has moved between these positions. The drive circuitry can also current that is directed to the actuator motor that is used to compensate for off-track movement to detect when the slider moves between these positions. In yet another embodiment, the drive circuitry monitors a rotational velocity of the storage disk to detect approximately when the slider moves between these positions.

Abstract: A data recording and/or playing method for recording or playing data to or from an optical disc having a first recording area, where a frame sync signal and the data are recorded, and a second recording area, where a predetermined pattern is preformed, and having address data recorded therein, while rotating the optical disc by a rotation drive unit. The optical disc rotated by the rotation drive unit is scanned by a head unit, and when the head unit is scanning the first recording area, the rotation drive unit is controlled in a first rotation control mode. When the head unit is scanning the second recording area, the rotation drive unit is controlled in a second rotation control mode.

Abstract: A magnetic pattern transfer method is disclosed. A magnetic pattern transfer master having a plurality of magnetic portions preformed with predetermined magnetic patterns is brought in proximity to a magnetic recording medium having a magnetic film to record the magnetic information, and a magnetic field is applied from an external source thereby to transfer the magnetic patterns to the magnetic recording medium. In order to improve the closeness between the magnetic film of the magnetic recording medium and the magnetic portions of the magnetic pattern transfer master, the magnetic patterns are transferred to the magnetic film of the magnetic recording medium during the process of fabricating the magnetic recording medium.

Abstract: In method of feedback control for active damping of slider air bearing vibrations in a hard disk drive slider, a slider is isolated from ground. A velocity signal is acquired from the slider. The velocity signal is filtered to acquire a vibration signal. The vibration signal is adjusted in amplitude to achieve an amplitude adjusted vibration signal. The amplitude adjusted vibration signal is applied to the slider to actively dampen vibrations in the slider.

Abstract: This invention relates to an optical scanning device for scanning an optical record carrier and detecting a tilt characteristic of the optical record carrier during scanning. The device includes a redirecting structure (26) arranged on an objective lens (10) to redirect a part of a radiation beam, when travelling towards the record carrier, differently to a main part of the radiation beam. The redirected beam part follows a path which is different to that of a path followed by the main beam part, towards a position sensitive detector in a detection system (16).