Abstract: An optical disk drive apparatus includes an optical head that directs a laser beam onto information pits formed in an optical disk, and a phase synchronization system that generates a clock signal that is phase-synchronized with respect to the information reproduction signal obtained from a reflected laser beam. The optical disk drive apparatus includes a measuring arrangement that measures the frequency of the clock signal, and a setting arrangement for setting the gain in the phase synchronization system proportionally with the frequency.

Abstract: A type of disc is judged at high reliability irrespective of a presence of information record or magnitude of disc eccentricity. A reproduction apparatus judges the type of an optical disc to reproduce information recorded on tracks of the optical disc. The disc is classified as a type of read-only optical discs whose tracks are formed with pits and as a type of recordable optical discs whose tracks are formed with wobbling grooves. The apparatus includes a motor which rotates the optical disc, a head which irradiates the tracks of the optical disc rotated by the motor with an optical beam and outputs two detection signals corresponding to reflected light from the optical disc, and a controller which judges the type of the optical disc according to changes of a period of a specific signal contained in a push-pull signal generated from the two detection signals by varying a rotating speed of the motor.

Abstract: An optical disk apparatus of the present invention measures a surface deflection component (shape of surface deflection) from a low-pass component of a compensating filter in a surface deflection measuring part provided in a DSP. Furthermore, the optical disk apparatus calculates timing at which a positional change in a surface deflection component in time required for focus jumping is a predetermined value or less in a timing calculating part, and starts focus jumping at the timing. Because of this, stable focus jumping is made possible.

Abstract: An optical disk of the present invention includes: a pre-recorded region in which pre-recorded data is recorded; a recordable region in which a first clock synchronization mark and first address information are recorded; and a synchronization region having a prescribed length which is positioned between the pre-recorded region and the recordable region.

Abstract: An optical apparatus includes a generator for generating a sine wave based on a rotating disc-shaped information carrier, and an eccentricity measuring device for measuring gain and phase of a sine wave corresponding to eccentricity of the information carrier based on the driving signal from the tracking control and on the measured rotation frequency. Also included is a waveform shaper for shaping the gain and phase of the sine wave generated by the sine wave generator using the measured gain and phase obtained by the eccentricity measuring device. An eccentricity correction is applied by adding together the sine wave shaped by the waveform shaper and the driving signal from the tracking control to drive an optical beam on a desired track of the rotating disc.

Abstract: An optical disk apparatus for reproducing, or recording, information from plural types of information carriers, including: two or more light sources with different wavelengths; converging parts for converging light beams emitted from the light sources on the information carrier; movement parts for moving the converged light beam in a direction substantially perpendicular to the surface of the information carrier; convergence condition detection parts for outputting a signal corresponding to the convergence condition of the light beam on the information carrier; amplitude detection parts for measuring the amplitude of the convergence condition signal; and focus control parts for driving the movement parts in accordance with the convergence condition signal and performing control so that the convergence condition of the light beam on the information carrier becomes substantially constant.

Abstract: An optical disc reproduction apparatus includes a sector detection section for detecting a sector; a sector reproduction time measuring section for measuring a reproduction time of the sector, and outputting sector reproduction time data which represents the measured reproduction time of the sector; an unrecorded portion detection section for detecting an unrecorded portion which is a portion of the sector in which no data is recorded; an unrecorded portion time measuring section for measuring a reproduction time of the unrecorded portion, and outputting unrecorded portion time data which represents the measured reproduction time of the unrecorded portion; and a sector determination section for determining whether the sector is an unrecorded sector or not, based on a relationship between the sector reproduction time data and the unrecorded portion time data, the unrecorded sector being a sector which is in an unrecorded state.

Abstract: An optical disc apparatus according to the present invention is usable for an optical disc including a bar code area and a control data area adjacent to the bar code area in a radial direction of the optical disc. The optical disc apparatus includes an optical head for directing an optical beam toward the optical disc so as to form an optical spot on the optical disc and output a signal in accordance with the optical beam reflected by the optical disc, a bar code area determination section for determining whether or not the optical spot is positioned on the bar code area of the optical disc based on the signal output by the optical head; and a control section for controlling the optical head so that the optical spot moves toward the control data area, when the optical spot is determined to be positioned on the bar code area.

Abstract: An optical disk apparatus for reproducing information from plural types of information carriers or for recording information to plural types of information carriers, has two or more light sources with different wavelengths, a converging part for converging a light beam emitted from each of the light sources on said information carrier, a movement part for moving the converged spot of the light beam converged by the converging part in a direction substantially perpendicular to the surface of the information carrier, a convergence condition detection part for outputting a signal corresponding to the convergence condition of the light beam on the information carrier, an amplitude detection part for measuring the amplitude of the signal of the convergence condition detection part, and a focus control part for driving the movement part in accordance with the output signal of the convergence condition detection part and for performing control so that the convergence condition of the light beam on the information ca

Abstract: An optical disc apparatus includes: a converging section for converging a light beam and irradiating a rotating information medium with the converged light beam; a moving section for moving the converging section, thereby moving a converging point of the converged light beam in a direction perpendicular to an information surface of the information medium; a converging state detection section for generating a focus servo signal which represents a converging state of the light beam on the information medium based on reflected light or transmitted light of the light beam from the information medium; a focus servo control section for controlling the moving section based on the focus servo signal, so that the light beam reaches a predetermined converging state on the information medium; and a focus pull-in section for turning ON the control by the focus servo control section, wherein the focus pull-in section turns ON the control by the focus servo control section in a case where the focus pull-in section determin

Abstract: In performing CLV readout, a target frequency is corrected based on current and target numbers of revolutions of a disk motor during a seek operation, thereby controlling the frequency of a read clock signal at a value approximately equal to the corrected target frequency. In performing CAV readout on the other hand, the frequency of the read clock signal is approximately equalized with a data read frequency at a seek destination. By performing these frequency control operations, data reading can be started quickly enough after the seek operation is finished. In reading out information from a recordable disk with wobbling tracks on a data portion, frequency control is performed using a wobble signal with respect to an unrecorded data portion, and phase locking control is performed using a data signal with respect to an address portion. In this manner, an address can be read out constantly.

Abstract: A speed profile constituting the target speed for the next drive process during searching is generated by target speed generating section 140 and tracking actuator 132 is driven using the error signal in regard to the speed of movement of the light beam calculated by movement speed detection section 141 from a pulse signal obtained by converting the TE signal to binary form. Also linear motor 139 is driven using the difference signal obtained from the target speed and the speed of movement. Tracking actuator 132 is controlled so as to suppress swinging of focusing lens 107 during searching and linear motor 139 moves, during searching, under tracking control to a target speed.

Abstract: An optical disk apparatus of the present invention measures a surface deflection component (shape of surface deflection) from a low-pass component of a compensating filter in a surface deflection measuring part provided in a DSP. Furthermore, the optical disk apparatus calculates timing at which a positional change in a surface deflection component in time required for focus jumping is a predetermined value or less in a timing calculating part, and starts focus jumping at the timing. Because of this, stable focus jumping is made possible.

Abstract: An optical disk drive apparatus drives an optical disk at a constant angular velocity (CAV). The optical disk is formatted under constant linear velocity (CLV). The phase error changes linearly from the inner most track to the outer most track. Tack pulse counter is provided to detect the radial position of the optical head on the optical disk. Calculators are provided to correct the phase error according to the radial position of the optical head.

Abstract: The object of the present invention is to realize a stable control and a stable signal reproduction in an optical disc device. When a head unit (110) is shifted in a radial direction or a reproduction speed is varied, a reproduction speed is detected based on a radial position at which the head unit is located and the number of rotaions of a motor (111), and settings of a focusing gain, a tracking gain, an amplification factor of an equalizer circuit (130), a band-limited frequency, a loop gain of a PLL circuit (131) and a divide ratio are varied based on said reproduction speed. Further, an accurate detection of an out of focus operation can be executed by using either one signal of a reflected-light quantity, an RF signal amplitude and a drive of a focusing actuator, or combined signals thereof. Thereby, a stable control and signal reproduction can be provided.

Abstract: An optical disk drive apparatus includes an optical head that directs a laser beam onto information pits formed in an optical disk, and a phase synchronization system that generates a clock signal that is phase-synchronized with respect to the information reproduction signal obtained from a reflected laser beam. The optical disk drive apparatus includes a measuring arrangement that measures the frequency of the clock signal, and a setting arrangement for setting the gain in the phase synchronization system proportionally with the frequency.

Abstract: An optical disk apparatus comprises a focusing means for focusing a light beam on a recording medium having first and second information faces; means for moving a focal point of the light beam in a direction substantially perpendicular to the information faces of the recording medium; means for detecting a reflected light from the recording medium; means for detecting a focus condition of the light beam on the basis of an output signal from the reflected light detecting means; a focus control means for driving the focal point moving means on the basis of an output signal from the focus condition detecting means, and controlling the light beam so that the focus condition of the light beam becomes a prescribed focus condition; and a focus jumping means for moving the focal point of the light beam from the first information face to the second information face by driving the focal point moving means.

Abstract: In order to achieve a processor that does not require processing time for branching processing and is ensured the flexibility of the processing content, an adder adds a start address stored in start address parts and selected by a selector and a stored content (relative address) of a program counter to output a current execution instruction address. An execution unit executes an instruction of the address of a program storing part. A comparator compares the address with an end address stored in end address storing parts and selected by a selector. When the addresses are matched, the selectors are switched, and the program counter is reset, so that branching can be performed without requiring an instruction cycle. The start address storing parts are rewritten by a supervisory processor, where appropriate.

Abstract: An optical disk apparatus for reproducing information from plural types of information carriers or for recording information to plural types of information carriers, has two or more light sources with different wavelengths, a converging part for converging a light beam emitted from each of the light sources on said information carrier, a movement part for moving the converged spot of the light beam converged by the converging part in a direction substantially perpendicular to the surface of the information carrier, a convergence condition detection part for outputting a signal corresponding to the convergence condition of the light beam on the information carrier, an amplitude detection part for measuring the amplitude of the signal of the convergence condition detection part, and a focus control part for driving the movement part in accordance with the output signal of the convergence condition detection part and for performing control so that the convergence condition of the light beam on the information ca

Abstract: A speed profile constituting the target speed for the next drive process during searching is generated by target speed generating section 140 and tracking actuator 132 is driven using the error signal in regard to the speed of movement of the light beam calculated by movement speed detection section 141 from a pulse signal obtained by converting the TE signal to binary form. Also linear motor 139 is driven using the difference signal obtained from the target speed and the speed of movement. Tracking actuator 132 is controlled so as to suppress swinging of focusing lens 107 during searching and linear motor 139 moves, during searching, under tracking control to a target speed.