Abstract: A plurality of tracks on an optical disk are optically read to obtain a signal containing a plurality of LOW segments. Each of the plurality of LOW segments should correspond to a certification pit. Accordingly, if the interval between LOW segment Xj and nth succeeding LOW segment Xj+n exceeds the length of one track, a defect pit that could be confused with a certification pit is judged as being present between two certification pits.

Abstract: A reflection type compound prism and an optical pickup apparatus employing the same. As a light beam is passed through the compound prism, a size of the light beam in a direction perpendicular to a reference plane is reduced by a first reflection surface, propagated toward an objective lens by second and third reflection surfaces and the size restored by reflecting the light beam from a fourth reflection surface forming an angle less than 45° with respect to the reference plane so that a height of an optical system is reducible to obtain a small thin optical pickup with a desired NA. The second and third reflection surfaces are spaced apart in a direction perpendicular to the reference plane by an amount close to a diameter of the light beam at a point of incidence of the light beam with the compound prism.

Abstract: Methods and apparatus for using physical synchronization markers during optical disc data acquisition are provided. In accordance with this invention, physical synchronization markers on optical discs and/or disc covers can be used to determine absolute and/or relative positions on the disc or cover and control data acquisition. A method for acquiring data includes detecting at least one physical synchronization marker and reading data in response to detecting the marker.

Abstract: A recording and/or reproducing apparatus for causing data recorded on a first recording medium to be stored in a second recording medium. This recording and/or reproducing apparatus includes a reproducing unit for reading out data from the first recording medium at a transmission rate faster than a standard readout rate of the first recording medium, a storage unit for storing the data read out from the first reproducing unit, a recording unit for storing the data read out from this storage unit on the second recording medium and a controlling unit for controlling the operation of the reproducing unit, storage unit and the recording unit. The controlling unit causes data to be read out from the storage unit at a transmission rate equal to the standard recording rate of the second recording medium and routed to the recording unit to record the supplied data in the second recording medium.

Abstract: It is an object of the present invention to provide an optical pickup apparatus appropriate for the notebook PC that can prevent structural resonance of the lens holder by arranging the focus coil and the tracking coil in a way to stabilize the weight balance, enable the tilt servo, and be composed in an extremely reduced thickness. An optical pickup apparatus composed to adjust the irradiation position of light beam to an optical disk by displacing an objective lens through a driving control of a lens holder holding the objective lens with a moving coil method, wherein an objective lens driving section is composed by arranging and fixing focus coils 7a, 7b so that a pair of coil main bodies be symmetrical about the objective lens 4 arranged at the middle of the lens holder 4, and arranging a pair of tracking coils 8a, 8b, 8c, 8d at both sides of the respective focus coils.

Abstract: It is an object of the present invention to provide an optical pickup apparatus which is capable of supporting multiple wavelengths in a reduced size without using a combined prism. An apparatus includes light emitting means having a plurality of integrated light emitting portions for emitting laser beams of different wavelengths, the light emitting means being adapted to selectively emit one of the laser beams of different wavelengths; photodetecting means for detecting the laser beam; and an optical system for directing the laser beam emitted from the light emitting means to the disc, and for directing the laser beam reflected by the disc to the photodetecting means, wherein the light emitting means is positioned such that a straight line connecting respective light emitting points of the plurality of light emitting portions is coincident with a tangential line of a track on a disc to be reproduced.

Abstract: An apparatus for detecting pre-pit information is disclosed, including an optical pickup, an optical-detecting section, a difference-detecting circuit, a first peak-value detecting circuit, a filtering circuit, a second peak-value detecting circuit, a differential potential-dividing circuit, and a comparator.

Abstract: An optical pickup apparatus conducts recording or reproducing information for an information recording plane of a first or second optical information recording medium and comprises a first light source and a second light source mounted on a same base board; a converging optical system; and a coupling lens. The converging optical system comprises an objective lens to converge a first or second light flux having passed through the coupling lens on a first or second optical information recording medium; and a diffractive structure to change a focal length in accordance with a wavelength of a light flux emitted from the first light source or the second light source.

Abstract: An optical system of an optical recording apparatus forms a main spot and sub-spots preceding and succeeding the main spot on a signal recording medium. The optical system is set such that the sub-spot is shifted from the main spot in the direction orthogonal to a signal track by a distance expressed by an expression (2k?1)P/4(k=natural number), in which P denotes a distance between adjacent signal tracks on the signal recording medium. Thus, the sub-spot succeeding the main spot can be used to effectively read the state of a signal recorded on the signal recording medium by the main spot.

Abstract: A reproducing apparatus capable of reproducing the data to be reproduced correctly by judging the lead-in region of first session on a multi-session disc. The reproducing apparatus reproduces a multi-session disc composed of a plurality of sessions, each comprising a lead-in region recording index information including the information of reproduction start time measured from the disc innermost peripheral position, program region recording program tracks storing contents to be reproduced, and lead-out region, corresponding to the start position of each program track stored in the multi-session disc. This reproducing apparatus comprises an optical pickup for reading out the index information of specified session, and a session judging unit for judging if the lead-in region of the specified session is the lead-in region of the first session of the multi-session disc or not, on the basis of the information of the reproduction time included in the index information being read out by the optical pickup.

Abstract: An optical storage device decreases the influence of return light to the laser light source and prevents an increase of power consumption even if high frequency superimposing is performed. The optical storage device applies drive current, to which a high frequency signal is superimposed, to the laser light source, and reads/writes data from/in the storage medium. The high frequency superimposing is set to OFF as a default to save power consumption, and high frequency superimposing is turned ON only when it is judged that servo is unstable, and high frequency superimposing is turned OFF when it is judged that servo is stable.

Abstract: A system and method for controlling operation of a motor system that addresses the design challenges for the small form factor optical disk system. The control system can be operable to read a physical sector address (PSA) from an optical medium, calculate a table index based on the PSA, enter a lookup table module to acquire reference data, and maintain a constant data rate transfer from the optical medium for a range of PSAs.

Abstract: A recording/reproducing apparatus and method are provided to record and reproduce data on and from a disk-shaped recording medium that has an address data area with embossed pits and a recording/reproducing area with a wobbling spiral groove. A wobble-signal processing circuit is used to extract a wobble signal from the signal the head obtains from the wobbling spiral groove and to provide the wobble signal to a PLL circuit to produce a sync signal therefrom. A pulse is produced at least during a wobble signal disturbance period occurring when switching between at least one of a recording and reproducing operation and provided to the PLL circuit in order to provide an unchanging sync signal during the wobble signal disturbance period to avoid the wobble disturbances from being carried over to the sync signal.

Abstract: A method and device are provided for jitter enhancement in an optical disc system. The optical disc system generates a signal that includes an effective component having a first slew rate, and a pre-pit component having a second slew rate larger than the first slew rate. The signal is fed to a slew rate control module having a predetermined slew rate that is larger than the first slew rate and smaller than the second slew rate. The slew rate control module outputs a component of the signal having a slew rate not larger than the predetermined slew rate, and suppresses a component of the information signal having a slew rate larger than the predetermined slew rate.

Abstract: In a write process through channels Ch1, Ch2, and Ch3, the deadline of each channel is set based on the transfer rate variable by the ratio of dummy packets to valid packets, and deadline information is written with write data on a disk. In a read process through a channel Ch4, the deadline is set according to the deadline information read with read data from the disk. Then, data is sequentially processed in order from the data having the earliest deadline. Considering the difference in transfer rate between outer and inner zones on the disk, a write zone is determined. When data is simultaneously recorded through the channels Ch1 and Ch2 on an ASMO in a groove-land record system, the data is sequentially recorded through the channel Ch1 on the groove and through the channel Ch2 on the land.

Abstract: Read/write components for AFM-based data storage devices are provided. In particular embodiments, a read/write component comprises lever means and a support structure, the lever means being connected to the support structure for substantially pivotal movement. The lever means provides first and second current paths between a pair of electrical supply lines on the support structure via which the lever means can be connected in use to power supply means operable in a write mode and a read mode. A write-mode heater is provided on the lever means in the first current path, and a read/write tip is provided on the write-mode heater. A read-mode heater is provided on the lever means in the second current path. Decoupling means is arranged to inhibit current flow to the write-mode heater via the first current path in use when the power supply means is operated in the read mode.

Abstract: To provide an optical recording medium and an eccentricity amount detecting device using the same that can detect an eccentricity amount representing a relative displacement amount in a radiation direction between a beam spot irradiated onto the optical recording medium and the optical recording medium. In the optical recording medium, a plurality (N) of servo areas (113) each including a first wobble mark (211) and a second wobble mark (212) and a plurality (N) of data areas for performing information recording and reproduction are arranged alternatively in a circumferential direction. Each of the servo areas is composed of a plurality of servo pattern areas (210a to 210c) arranged in the radial direction, which vary in a distance in the circumferential direction between the first wobble mark and the second wobble mark. The plurality of servo pattern areas include the same number of tracks, and the number is less than N/(2×?).

Abstract: An optical information recording method and a device which can record information with a laser light irradiating direction kept constant even if an information recording surface of an optical information recording medium is inclined and, a recording medium having a program therefor recorded thereon are provided. When performing OPC, a relational expression between a recording power and asymmetry (a standard expression), a relational expression between a differential light intensity value and a recording power (a first detection expression), a relational expression between a recording power and a difference between a differential light intensity value and a reflected light amount ratio (a second detection expression), a relational expression between a reflected light amount ratio and a recording power (a third detection expression), a differential light intensity value with which optimum asymmetry can be obtained, a recording power, a reflected light amount ratio and the like are determined and stored.

Abstract: The present invention is directed to an object lens drive device adapted for moving an object lens (21) in a focus direction of optical axis direction and in a tracking direction perpendicular to the optical axis direction, and comprises a fixed portion (10) provided in such a manner that a supporting shaft (14) is projected, a movable portion (11) comprised of an object lens (21), and a bobbin (16) adapted so that the object lens (21) is attached and a hole (18) through the supporting shaft is inserted is formed, the bobbin (18) being supported movably along the supporting shaft and rotatably with the supporting shaft being as center, a drive portion including a magnet portion provided at either one of the fixed portion and the movable portion, and a coil portion (22) provided at the other portion to move the movable portion along the supporting shaft to thereby move the object lens in the focus direction, and to rotate the bobbin with the supporting shaft being as center to thereby move the object lens in t

Abstract: A method is designed for recording information on an optical disk in the form of a sequence of pits along a track of the optical disk.