Matsushita Electric Industrial Co., Ltd.

Panasonic Corporation

Matshushita Electric Industrial Co., Ltd.

Takashi Kishimoto

Katsuya Watanabe

Takeharu Yamamoto

Kenji Fujiune

Rie Takahashi

Mitsurou Moriya

Hiroshige Ishibashi

Hiromichi Ishibashi

Kenji Kondo

Yoshihiro Kanda

Yuuichi Kuze

Shin-ichi Yamada

Yuichi Kuze

Yoshiho Gotoh

Kousei Sano

Shin-ichi Kadowaki

Mitsuro Moriya

Tatsushi Bannai

Takeshi Shimamoto

Shuichi Yoshida

Akihiro Yasuda

Kouichi Ikeuchi

Takuya Asano

Kazushi Andoh

Hiroyuki Yamaguchi

Akihiro Arai

Eiji Ueda

Shinichi Yamada

Tetsuya Shihara

Yuu Okada

Jun Kikuchi

Masayoshi Shioya

Tatsuya Takeuchi

Yoshirou Kashiwabara

Shin-Ichi Yamada

An optical disc apparatus has: a spherical aberration correction unit () which corrects the spherical aberration generated in a light spot on a recording layer; a control unit () which focuses a light beam on a predetermined recording layer, and shifts the focal point position of the light beam from the current recording layer to another recording layer; and a focus jump control unit () which controls correction of spherical aberration and shift of the focal point position based on the interlayer distance between the current recording layer and a recording layer which adjoins in a direction opposite to a direction of shifting the focal point position of the light beam. By this configuration, focus jump is stably executed.

Optical disc apparatus, focus control method and integrated circuit

Provided are an optical disc discrimination method, an optical disc device and an integrated circuit that enable to accurately discriminate the type of an optical disc. The optical disc discrimination method comprises a first seeking step (S) of performing a seek operation to a predetermined reference address in a user data area; a second seeking step (S) of performing a seek operation from the reference address sought in the first seeking step (S) to a predetermined target address in a physical information area, an address reading step (S) of reading a current address at a position sought in the second seeking step (S), and an optical disc type determination step (Sthrough S) of determining the type of the optical disc loaded in the optical disc device, based on the current address read in the address reading step (S).

Optical disc discrimination method, optical disc device and integrated circuit

An object of this invention is to improve stability of tracking control and improve recording and reproduction performance. The tracking control device comprises a main push-pull signal generation section, which generates a main push-pull signal based on a signal obtained by photoelectric conversion of return light of the main beam; a microcomputer, which detects an other-layer stray light signal component included in a signal obtained by photoelectric conversion of return light of the sub-beam; a signal correction section, which corrects the signal obtained by photoelectric conversion of the return light of the sub-beam, based on the other-layer stray light signal component; and a sub-push-pull signal generation section, which generates a sub-push-pull signal based on the corrected signal obtained by photoelectric conversion of the return light of the sub-beam.

Tracking control device, tracking control method, and optical disc device

After an optical disk drive according to the present invention has been loaded with an optical disk and before the operation of recognizing the type of the given disk is finished, the drive presumes one of multiple types of candidate optical disks, from/on which data is readable and writable using a light beam with the shortest wavelength among the candidate disks, to be the disk being driven by the motor now and gets the beam for the presumed type of disk radiated from a light source (Step (A)). Next, the drive gets the disk spun at a rotational velocity that realizes a linear velocity equal to or higher than a standardized normal velocity when data is read from the presumed type of disk (Step (B)). Thereafter, the drive starts a focus control in a situation where the spot of the beam being formed on the disk is moving on the disk at the linear velocity equal to or higher than the normal velocity (Step (C)). And then the drive performs the operation of recognizing the type of the disk by the light beam reflected from the disk under the focus control (Step (D)).

Optical disk drive for discriminating types of optical disks

The invention provides a tracking control device, a tracking control method, and an optical disc apparatus that enable to stably perform the tracking control, and reduce an influence of stray light from the other layer on the tracking control. A sub push-pull signal correcting section corrects a sub push-pull signal to be generated from returning light of a sub beam in such a manner that a track crossing component of a main push-pull signal to be generated from returning light of a main beam, and a track crossing component of the sub push-pull signal to be generated from the returning light of the sub beam are canceled. A low pass filter reduces a high frequency component of the sub push-pull signal corrected by the sub push-pull signal correcting section. A subtractor subtracts a sub push-pull signal passing the low pass filter from the main push-pull signal to thereby generate a tracking error signal.

Tracking control device, tracking control method, and optical disc apparatus

An optical disk drive according to the present invention has the ability to read data from multiple types of optical disks, each of which includes at least one information storage layer. The drive includes: a driving mechanism, which is loaded with a selected one of the optical disks of the multiple types and which rotates the optical disk; an optical pickupfor irradiating the optical disk, which has been loaded into the driving mechanism, with a converged light beam, thereby generating an electrical signal based on light that has been reflected from the optical disk; and a control section (ODC) for controlling operations of the driving mechanismand the optical pickup. The control sectionincludes a right/wrong side determining section for determining, by reference to the electrical signal generated by the optical pickup, whether or not the optical diskhas been loaded into the driving mechanismwith the other surface opposed to the optical pickup

Optical disk unit and driving method therefor

An optical disk device includes a DPDTE signal generating section that detects misalignment between a light spot and a mark or a pit, an FE signal generating section, an optical crosstalk correcting section which corrects a signal output by the FE signal generating section using the DPDTE signal generating section, and a focus control section which controls an actuator so that a light beam converges on an information layer. The DPDTE signal generating section detects the misalignment on the basis of phase information obtained from signals received from predetermined light receiving areas. The optical crosstalk correcting section performs a correcting operation of removing a signal component from predetermined receiving areas of a detector which component is used for a DPDTE signal, the signal component being contained in the signals from the predetermined light receiving areas of the detector which signals are used by the FE signal generating section.

Optical disk device, method of controlling optical head, and control device for optical head

An optical disc apparatus of the present invention includes an optical head () including a lens disposed at a position shifted from a traverse axis in a tangential direction, a traverse motor () as a second moving unit that moves the optical head () in a direction traversing tracks of the optical disc (), a number-of-tracks calculating part () that calculates, as the number of tracks to be sought, the number of tracks that the optical head will traverse when moving from a first address to a second address of the optical disc (), a tracking-drive-signal-at-seek generating part () and a traverse-drive-signal-at-seek generating part () as seek controlling units that move a convergent point of an optical beam from the first address to the second address, and a number-of-tracks correcting part () that corrects the number of tracks to be sought according to a shift amount of the lens from the traverse axis.

Optical disc apparatus and seek processing method

An optical disk apparatus according to the present invention is an optical disk apparatus for performing at least one of: recording data to a plurality of types of optical disks including a recordable optical disk and a read-only optical disk which are produced according to the BD specifications; and reproducing data from the optical disks. This apparatus includes: a means () for irradiating a management areaof an optical diskwith a light beam while not performing tracking control, and generating a track position signal (push-pull TE or phase difference TE) from light which is reflected by the management area; and a disk determination means for determining, based on the track position signal obtained from the management area, whether the optical diskmounted in the optical disk apparatus is a recordable optical disk or a read-only optical disk.

Optical disc judgment method and optical disc device

A standard reproduction model for ensuring real time reproducing on a disk-shaped information recording medium, includes a pickup () that reads the real time data from the information recording medium, a buffer memory () that temporarily stores the real time data read by the pickup, and a decoding module () that reads the real time data from the buffer memory () and processes the read real time data. An access time Tacc of the standard reproduction model is expressed by the following formula,where dN is a difference in rotational speed of the disk-shaped information recording medium, Trev is a rotation waiting time at a target access position, A and B are constants.

Reproducing method for reproducing real time data from a disk-shaped information recording medium

An optical disc device of the present invention includes spherical aberration changing means for changing spherical aberration occurring on a converging position of a light beam converged by a lens, an actuator for moving the spherical aberration changing means in a relatively precise manner, and an actuator for moving the spherical aberration changing means in a relatively rough manner. The optical disc device drives a second actuator and a third actuator based on a signal of spherical aberration detecting means and performs control so that spherical aberration is almost 0. The third actuator moves the spherical aberration changing means based on a direct current component included in a signal of the spherical aberration detecting means, and the second actuator moves the spherical aberration changing means based on an alternating current component included in the signal of the spherical aberration detecting means.

Optical disc device

Method and apparatus for recording real-time data into an optical disc

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.

Optical disc apparatus

The present invention provides a deficiency detecting apparatus that can accurately detect dusts and deficiencies on an optical disk even when an emitting power of a laser light source changes. The deficiency detecting apparatus is provided with a deficiency detecting section for detecting deficiencies or the like on an optical disk by reflected light, and a power adjusting section for adjusting an emitting power of a laser light source to be an optimum value. The deficiency detecting section can accurately detect the deficiencies on the optical disk even when the laser power changes by comparing a threshold value, which is determined in accordance with the adjustment result of the power adjusting section, with a value in accordance with the reflected light.

Deficiency detecting apparatus for optical disk

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Nara, Japan

Takashi Kishimoto