Matsushita Electric Industrial Co., Ltd.

Panasonic Corporation

Panasonic Intellectual Property Management Co., Ltd.

Yuuichi Kuze

Katsuya Watanabe

Kenji Fujiune

Shin-ichi Yamada

Kousei Sano

Kenji Kondo

Shin-ichi Kadowaki

Takashi Kishimoto

Daisuke Ogata

Akihiro Yasuda

Akira Yoshikawa

Shinichi Konishi

Yoshihiro Kanda

Shinichi Yamada

Masatoshi Yajima

Katsuhiko Yasuda

Akihiko Nishioka

Mamoru Shoji

Hiromichi Ishibashi

Mitsurou Moriya

Takeharu Yamamoto

Takahiro Sato

Eiji Ueda

Takeshi Shimamoto

Hiroshige Ishibashi

Akihito Yoshimi

Shin-Ichi Yamada

Hirokuni Hagita

Daichi Tamaki

An optical disc device includes: an optical pickup including a first laser light source that emits laser light, an objective lens that focuses the laser light emitted from the first laser light source onto an optical disc, and a light receiving element that receives reflected light from the optical disc, and performs photoelectric conversion on the reflected light received to output a received-light signal; an FS signal generator that generates an FS signal indicating the light amount of the reflected light from the optical disc, based on the received-light signal from the light receiving element; and a dirt determiner that determines that dirt is present in the optical pickup, when the peak level of the FS signal is less than a dirt determination threshold, and controls the light receiving element to increase the peak level of the received-light signal from the light receiving element.

Optical disc device and recording and reproduction device

An optical disc drive device includes a spindle motor that rotates an optical disc, an OPU, a first controller that causes the spindle motor and the OPU to read recorded data from the rotating optical disc, and an transmitter that transmits the read recorded data to a signal processing device disposed external to the optical disc drive device. The recorded data transmitted by transmitter is stored in a buffer provided in the signal processing device. The first controller decreases the rotational speed of the optical disc based on free space information indicating the free space of the buffer.

Optical disc drive device and playback device

An optical disc device according to the present invention performs, in parallel, a first control to convey a first tray in the first optical disc drive group from the disc replacing position to the recording and reproducing position, and a second control to convey a second tray in the second optical disc drive groupR from the recording and reproducing position to the disc replacing position. The second tray is opposed to the first tray.

Optical disc device including a carrier for holding optical discs in a stacked state

The optical disc apparatus of this invention includes: an optical pickup, which irradiates an optical disc with a light beam and generates a light detection signal based on the beam reflected from the disc; a search section, which controls the pickup before data is written on a storage area of the disc, thereby adjusting the beam spot location and searching a reference one of information layers stacked for a defective area in the storage area of the disc; a defect decision section for detecting an error based on the detection signal and determining a portion of the storage area, where the error has occurred, as the defective area; a defect size measuring section for measuring the size of the defective area in an area of the reference layer and generating a defect information list indicating there is the defective area in the area of the reference layer; and a recording range control section for managing, by reference to the list, the storage area such that no data will be written on a perpendicularly projected area defined by projecting the defective area of the reference layer perpendicularly to another information layer.

Optical disc device

An object of this invention is to measure the tilt quantity of, and perform a tilt control on, an optical disc accurately without depending on the rotation control method. An optical disc drive includes: a motor for rotating an optical disc; an optical system for irradiating the optical disc with a light beam; a moving mechanism for moving the optical system along the radius of the optical disc; a focus control section for controlling movement of the optical system perpendicularly to the optical disc based on drive values, thereby focusing the light beam onto a storage layer of the optical disc; and a tilt control section for measuring the tilt quantities of the storage layer at multiple different radial locations on the optical disc based on drive values for the respective radial locations when the focus control section focuses the light beam there. When the tilt control section measures the tilt quantities, the motor keeps the rotational frequency of the optical disc constant and the tilt control section uses the drive values obtained at the respective radial locations.

An optical disc apparatus includes: a defect detecting sectionfor detecting, based on a light detection signal and with respect to a preset detection reference level, a fingerprint or a bubble on the discas a defect to output a defect detection signal; and a waveform shaping sectionto output a hold signal that holds, in response to the defect detection signal, a signal from a tracking control sectionat a level just before the defect has occurred. The apparatus is initially operated not to hold the signal from the tracking control sectioneven if there is a defect. But once a tracking failure has occurred during a read operation, settings are changed to hold the signal from the tracking control sectionagainst the defect while the read operation is retried.

This optical disc drive can read and/or write data from/on an optical discwith multiple information layers including first and second information layers. The drive includes: a light sourcethat emits the light beam; an objective lens; an actuatorfor moving the objective lens perpendicularly to the information layers; a focus error generatorfor generating a focus error signal representing how much the light beam has been converged on a target one of the information layers; and focus control means for forming a focal point of the light beam on the target information layer by driving the actuator in accordance with the focus error signal. According to the present invention, while a focus jump is being made to shift the focal point of the light beam from the first information layer of the optical discto the second information layer thereof by moving the objective lens, wavelengths and/or numerical apertures for the light beam are changeable while the objective lensis moving.

An optical disk drive includes: a light source for producing a light beam; an objective lens for converging the light beam; an actuator for moving the objective lens with respect to an optical disk; a converging state detecting section for generating a focus error signal representing a converging state of the light beam on an information storage layer of the optical disk; and a focus control section for controlling the operation of the actuator such that the focus position of the light beam matches its target focus position as closely as possible in accordance with information about the target focus position and the focus error signal. The optical disk drive changes the target focus positions of the light beam when modes of operation are switched from a read mode into a write mode, or vice versa.

Optical disk drive with target focus control

The purpose is to provide an optical disc apparatus which can accurately calculate a gain for focus control. An optical apparatus () includes: an FE generator () for generating an FE signal; an AS generator for generating an AS signal (); a normalization operator (); an Fc filter (); a selector (); a spherical aberration setting device (); an FE amplitude measuring device (); an Fc pull-in instructor (); an after-pull-in AS measuring device (); and a gain operator (). The optical apparatus obtains an amplitude of the FE signal before the focus is pulled in, and obtains a level of the AS signal after the focus is pulled in to adjust a focus gain.

Optical disc apparatus and semiconductor device

It is an object of the present invention to provide a method for absorbing individual variance between optical disc devices or optical discs, and for determining the optimal servo adjustment position even with optical discs in which no convex/concave pit string is present. When mounting a disc, servo position adjustment is performed in at least two stages: first servo position adjustment and second servo position adjustment. Also, the second servo position adjustment is performed by recording a predetermined signal after the first servo position adjustment and reproducing the track where the predetermined signal was recorded.

Servo position adjustment method and servo position adjustment device

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.

An optical disc drive includes: a light source; a focusing section; a focus shifting section for shifting the focal point of light by changing the position of the focusing section perpendicularly to a data storage layer of a given optical disc in accordance with a control signal; a light receiving section for receiving, at multiple areas, the light reflected from the data storage layer and generating light quantity signals; a signal generating section for generating a focus error signal based on the light quantity signals; and a control section for generating the control signal responsive to the focus error signal such that the focal point is transferred to a focus controllable range. The control section generates the control signal such that the focal point is decelerated at a first acceleration and then at a second acceleration. The absolute value of the second acceleration is smaller than that of the first acceleration.

Optical disc drive which uses a train of pulses to shift the focus of a focusing section

An optical disc apparatus is provided, which comprises a lens tilting section for tilting an objective lens to correct coma aberration occurring in a light beam spot focused on an information surface of an optical disc, a spherical aberration correcting section for correcting spherical aberration occurring in a light beam spot focused on the information surface, and a lens tilt-spherical aberration correction control section for controlling the spherical aberration correcting section to change an amount of spherical aberration correction performed by the spherical aberration correcting section depending on a tilt of the objective lens tilted by the lens tilting section.

Optical disc apparatus and spherical aberration correction controlling apparatus

An optical disc apparatus includes a control section. The control section performs a first search while the tracking control is in the off state. The first search is for searching for a plurality of sets of the focus positions of the light beam and the spherical aberration amounts such that an amplitude of the tracking error signal is greater than a predetermined value. The control section performs a second search while the tracking control is in the on state. The second search is for determining a set of the focus position of the light beam and the spherical aberration amount such that the reproduced signal quality index is substantially optimal, among the plurality of sets of the focus positions of the light beam and the spherical aberration amounts obtained in the first search.

Optical disc apparatus, an optical disc method, and a semiconductor integrated circuit capable of adjusting a focus position of a light beam and a spherical aberration

An optical disc drive according to the present invention reads and/or writes data from/on an optical disc having at least one information layer with a light beam and includes: a spherical aberration detecting section for generating a spherical aberration signal representing a spherical aberration produced at a focal point of the light beam on the information layer of the disc; a spherical aberration changing section for changing the spherical aberration; a spherical aberration regulating section for generating an aberration correction signal to correct the spherical aberration by driving the changing section; and means for detecting a value of the aberration correction signal that minimizes the spherical aberration when the focal point of the light beam is located on the information layer of the disc and for detecting the depth of the information layer, which corresponds to a distance from the information layer on which the focal point of the light beam is located to the surface of the disc, based on the value.

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Osaka, Japan

Yuuichi Kuze