Abstract: An information recording apparatus for recording tracks includes: a rotation drive section (RDS) that supports and rotates a master disk with a resist layer; an exposure beam emitting section (EBES) deflectably applying an exposure beam to the disk to form a spot thereon; a relative movement drive section (RMDS) translating the RDS relatively to the spot in a radial direction of the disk; an emission controller supplying the EBES with an instruction for modulating an intensity of the exposure beam according to data to be recorded; and a movement controller supplying the RMDS with an instruction for moving the RDS with the rotating disk by a predetermined moving amount for each disk rotation.

Abstract: A dielectric reproducing apparatus is provided with: a probe for applying an electric field to a dielectric material of a dielectric recording medium; a return electrode for returning the electric field applied from the probe; an inductor placed between the probe and the return electrode; an oscillator which oscillates at a resonance frequency determined from the inductor and a capacitance formed in the dielectric material just under the probe; an alternating current (AC) signal generation device for generating an AC signal which is applied to the probe; a frequency modulation (FM) demodulator for demodulating a FM modulation signal modulated by the capacitance corresponding to the polarization state owned by the dielectric material just under the probe; and a phase-shift keying (PSK) demodulator for reproducing data from the demodulated signal.

Abstract: A recordable optical information recording medium having an address t for each sector, comprises: an area A1 starting from an address t1 to which access is made only when a recording apparatus performs recording operation; an area A2 starting from an address t2 to which access is made either when the recording apparatus performs the recording operation or when the recording apparatus performs reproducing operation; and an area A3 starting from an address t3 to which access is made either the recording apparatus or a reproducing apparatus performs recording or when either recording apparatus or the reproducing apparatus performs reproducing. The addresses t are set consecutively with respect to a physical arrangement of the sectors in each of the areas A2 and A3, and the area A1 has at least on inconsecutive part at which the addresses t are not consecutive with respect to the physical arrangement of the sectors.

Abstract: A method of recording data on a compact disc is provided includes modulating the data of 1 byte to p-channel bits, recording the modulated data when a minimum mark length is greater than 0.5 ?m and smaller than 1.0 ?m, p/q is greater than 4.5 and smaller than 8 when the minimum mark length corresponds to q-channel bits, and a format efficiency is greater than 0.6 and smaller than 1.0. Thus, data can be recorded on an existing compact disc at a higher density.

Abstract: An optical recording medium and method of formatting the optical recording medium is disclosed. In the present invention, the location information of the supplementary spare area, if assigned, is reset when the optical recording medium is formatted. The resetting of the location information results in consistency between a file system and a driver of the optical recording medium with respect to the supplementary spare area.

Abstract: In order to perform simultaneous recording and reproduction, a large capacity of buffer memories were required. In addition, it was difficult to record data while reproducing data which was recorded by a different apparatus. The present invention has an objective of providing an information recording medium, a simultaneous recording and reproduction method, and an information recording and reproduction apparatus which guarantee simultaneous recording and reproduction. The simultaneous recording and reproduction is guaranteed by reproducing data recorded in an area having at least a minimum size fulfilling the simultaneous recording and reproduction condition which allows for four access operations, recording data in an area having at least the same size, and performing reproduction and recording alternately by switching reproduction to recording when the data amount in the reproduction buffer becomes full and switching recording to reproduction when the data amount in the recording buffer becomes empty.

Abstract: An optical head in which focusing error is detected by a spot size method used for recording and/or reproducing information signals on or from an optical disc. The optical head includes a unit for correcting the spot shape between the objective lens and a photodetector device. The spot shape correcting unit corrects part or all of light spots formed on the photodetector by a light beam reflected back by the optical disc so that the spot diameter in a direction traversing a track on the optical disc will be larger than the spot diameter along the track.

Abstract: A drive current or a drive voltage is controlled corresponding to change of load by sampling the drive current or drive voltage of a motor to move an optical pickup and then detecting change of the sampling signal as change of the optical pickup when it is moved. Moreover, change of the sampling signal is obtained from a difference of the sampling signals by comparing these sampling signals at the first and second points. Comparison of these sampling signals is conducted in unit of drive pulse.

Abstract: A disk device in which at the recovery job of a focus pull-in operation, a CPU supplies servo control means with the respective correction values of the rotational speed of an optical disk and the moving speed of a lens which are described in the data table of a RAM, and performs the focus pull-in operation and determines whether or not the focus pull-in operation is successfully performed at the respective adjustment steps, and if the focus pull-in operation is successfully performed, the servo control means changes the amount of movement of the lens in response to a surface swing of the optical disk.

Abstract: A recording apparatus for recording modulated data on a rewritable recording medium includes a data modulation section for modulating data in accordance with a prescribed modulation rule; a parameter value changing section for changing at least one parameter value of the prescribed modulation rule; and a recording section for recording the data modulated in accordance with the prescribed modulation rule on the recording medium.

Abstract: An apparatus for setting an offset in a DVD player includes: an offset measuring unit which measures one or more offset parameters for initial reproducing operations of the DVD player; and an offset setting unit which, when the offset measuring unit measures the one or more offset parameters a number of times, calculates an average value of the measured offset values of the one or more offset parameters and sets, for each of the one or more offset parameters of the DVD player, the average value as a set offset value.

Abstract: An apparatus and a method of playing an optical recording medium, including a method of compensating for a tilt by a real time tilt detection before and during a playing operation of the optical recording medium. A tilt compensating apparatus includes an optical pickup, a tilt adjuster which adjust a tilt of the optical pickup, a jitter detector which detects a jittering amount of a playing signal generated from the optical pickup, and a tilt controller which controls operations of the tilt adjuster so as to have the jittering amount become minimum by comparing the jittering amount detected before a reproduction of a content of the optical recording medium with a first jittering reference value, and comparing the jittering amount detected during the reproducing of the optical recording medium, per a certain period, with a second reference value. Since the reproduction of the optical recording medium is performed after a tilt compensation, it takes a shorter time to start the reproduction operation.

Abstract: A disc driving apparatus and an information readout method according to the present invention realize optimum servo control of a readout unit in reading out the information from a recording medium having lands and grooves. The disc driving apparatus includes a unit for correcting tracking error signals, a unit for inverting signals corrected by the correcting unit to generate inverted tracking error signals, a unit for detecting which of the lands and the grooves the readout unit is scanning, and a unit for selecting the tracking error signals or the inverted tracking error signals according to the results of detection by the detection unit to tracking-control the readout unit by the selected signals.

Abstract: An optical disk apparatus is disclosed which makes accesses on a block-by-block basis to an optical disk having a recording track segmented into first recording areas by first address information correlated with wobbling information of the recording track, the block being a unit for error correction consisting of a plurality of the first recording areas. The optical disk apparatus comprises an access control unit which, when an access is made to a second recording area consisting of a plurality of the first recording areas, provides access control in sequence without applying any data modulation and/or demodulation process to each of the plurality of first recording areas constituting the second recording area.

Abstract: A focus control is performed on the basis of a focus error signal indicative of a deviation amount from a focus state in a recording layer of a laser beam emitted for reproducing information to an optical disk having a plurality of recording layers. Specifically, at the time of focus-jumping a laser beam from a recording layer to another recording layer, an acceleration pulse or a deceleration pulse as a brake signal for making a focus jump is applied to a focus drive signal for controlling driving of an optical pickup for emitting a laser beam. The timing of applying each of the brake signals is variably set on the basis of the level of a focus error signal of a recording layer as an object of the focus jump. As a result, the focus jump can be accurately made in accordance with variations in the level of the focus error signal caused by variations in transmittance of light according to materials of the recording layers.

Abstract: An optical disc drive includes an optical head having a stationary portion and a movable portion. The movable portion supports an objective lens for converging a beam emitted from the stationary portion on an optical disc. The movable portion moves radially across an optical disc in order to irradiate the beam on a desired track of the optical disc. The optical disc drive is further provided with an aberration correcting lens that corrects aberration caused by the objective lens. The aberration correcting lens is mounted on the movable portion so as to be movable in a direction substantially orthogonal to a movable direction of the movable portion, which may parallel or perpendicular to the optical disc. The aberration correcting lens is moved in accordance with a variation of the aberration caused by the objective lens.

Abstract: A recording and/or reproducing apparatus and a method of controlling the same. The method of controlling the apparatus for recording information in or reproducing information from a disc having a wobbled track, the method includes detecting a wobble signal recorded in the wobbled track, and removing an error component occurring during the recording or the reproducing, based on the detected wobble signal. Accordingly, errors arising from a variety of factors can be accurately compensated for during a recording or reproducing operation.

Abstract: Provided is an actuator for use in a pickup device, which can improve the quality of the pickup device by reducing a lens distortion even when the frequency of an electromagnetic drive rises beyond a servo band and causes resonance of a lens holder. An adhesive layer (11) is formed between an outer peripheral portion (6A) of an objective lens (6) and a lens holder (4). This adhesive layer (11) has a sufficient thickness dimension enough to absorb deformation of the lens holder (4) even when the lens holder (4) is deformed due to resonance. Even when the frequency at which an electromagnetic drive (9) operates rises beyond the servo band and causes resonance of the lens holder (4), the adhesive layer (11) functions as a buffer so that deformation of the lens holder (4) is less transmitted to the objective lens (6).

Abstract: An objective lens in which a first wavelength is used in reading a first optical disk, a second wavelength is used in recording or reading a second optical disk, and a phase shifter provided with annular step portions having a center coincident with an optical axis is formed in a single surface of the objective lens, the phase shifter producing a phase difference with respect to light having the first wavelength and light having the second wavelength, is presented. The objective lens can read well both a CD and a DVD.

Abstract: A drive reads and/or writes data from/on an optical data storage medium, including first and second data storage layers stacked in this order toward the depth thereof, by radiating light through the surface. The drive includes a light source, a lens, a light detector, and a layer sensor. The light source emits the light. The lens produces a focal spot. The light detector includes at least one photodetector for receiving the light and generating a light quantity signal. The photodetector is used as a layer-sensing photodetector not receiving the light from the second data storage layer when the focal spot is located on the first data storage layer and receiving the light from the first data storage layer when the focal spot is located on the second data storage layer. The layer sensor determines, by the light quantity signal, where the focal spot is now located.