Sony Corporation

Tsutomu Ishimoto

Kimihiro Saito

Seiji Kobayashi

Hisayuki Yamatsu

Roderick Koehle

Takao Kondo

Masanobu Yamamoto

Yoshio Ohashi

Masaru Uryu

Kazuhiko Fujiie

Junichi Horigome

Motohiro Furuki

Isamu Nakao

Toshihiro Horigome

Ariyoshi Nakaoki

Sunmin Kim

An optical drive device includes first and second light sources, an objective lens configured to receive a first light emitted from the first light source and a second light emitted from the second light source and to irradiate both the first light and the second light to an optical disc recording medium, a first focus mechanism configured to drive the objective lens in a focus direction, a second focus mechanism configured to change collimation of the second light incident to the objective lens and changing the focusing position of the second light independently of the first light, a first focus servo control unit configured to drive the first focus mechanism, an error signal subtraction unit configured to subtract the first focus error signal from a second focus error signal, and a second focus servo control unit configured to drive the second focus mechanism.

Optical drive device and focus servo control method

A recording device includes: a rotation driving unit that rotates an optical medium having a reference face and a recording layer, at a constant velocity; a light irradiating unit that irradiates the optical recording medium with first and second light through a common object lens; an infocus position adjusting unit that performs adjustment to focus; a light receiving unit that receives reflection light from the reference face; a reproducing clock generating unit that generates a reproducing clock on the basis of a light reception signal; a radial position detecting unit that detects the radial positional information on the basis of the light reception signal and the reproducing clock positional information; a frequency adjusting unit that changes a frequency of an input reference signal; and a recording unit that performs mark recording on the recording layer using the signal obtained by the frequency adjusting unit as a recording clock.

Recording device and recording method

A recording apparatus for performing information recording using formation of marks by focusing a first light with an objective lens at a given position in a recording layer included in an optical disc recording medium, includes: a rotation driving unit for rotating the optical disc recording medium; a focus servo control unit for condensing a second light which is different from the first light on a reflection film, and for controlling a position of the objective lens so that a focal position of the second light follows the reflection film; a recording position setting unit for setting an information recording position of the first light in a focus direction by changing the collimation of the first light; a surface wobbling amount estimating unit; and a surface wobbling estimation amount acquisition control unit for acquiring a surface wobbling estimation amount for each rotation angle within one revolution of the disc.

Recording apparatus and control method

A recording apparatus for performing information recording using formation of marks by focusing a first light with an objective lens at a given position in a recording layer included in an optical disc recording medium, includes: a rotation driving unit; a focus servo control unit for condensing a second light on a reflection film and for controlling a position of the objective lens; a recording position setting unit for setting an information recording position of the first light in a focus direction; a tracking servo control unit for controlling a position of the objective lens; an eccentricity amount estimating unit for estimating an eccentricity amount of the optical disc recording medium; and an eccentricity estimation amount acquisition control unit for acquiring an eccentricity estimation amount for each rotation angle within one revolution of the disc.

A movement speed of a lens included in an optical pickup is calculated by differentiating a total reflection return light quantity that is detected by emitting laser light and near-field light onto a signal recording surface of a rotationally driven optical disc. On the basis of the calculated movement speed, processing for driving the optical pickup or the lens included in the optical pickup is controlled. For example, in a case where the calculated movement speed exceeds a permissible speed set in advance, retreat processing is performed for moving the optical pickup or the lens included in the optical pickup apart from a surface of the optical disc.

Optical disc apparatus and optical disc drive control method

Directed to freely adjusting an emission period of a semiconductor laser. In the present invention, pulsed light serving as pulse-shaped laser light (LL) is emitted from a semiconductor laser (), and a laser drive voltage (DJ) that is generated on the basis of a pulse signal (SL) and that has pulse-shaped drive voltage pulses (DJw) is applied to the semiconductor laser (). At this time, a short-pulse light source () varies a voltage period (TV) corresponding to an interval between the drive voltage pulses (DJw), thereby varying a set period (TS) corresponding to an interval between generated signal pulses (SLw) in the pulse signal (SL).

Short-pulse light source, laser light emission method, optical device, optical disc device, and optical pickup

In an information recording method, information is recorded to semiconductor memory when at least a specified amount of free space exists in the semiconductor memory. Information is recorded to magnetic memory when the free space in the semiconductor memory is insufficient but at least a specified amount of free space exists in the magnetic memory. Information is recorded to optical memory when the free space in both the semiconductor memory and the magnetic memory is insufficient. When retrieving recorded information, an access count is incremented, and information with a comparatively high access count is moved to the semiconductor memory, while information with a comparatively low access count is moved to the optical memory. Information is thus recorded to a recording medium suitably selected from among semiconductor memory, magnetic memory, and optical memory, thereby making effective use of each memory type.

Information recording method and information recording apparatus

A disk device includes a main control unit controlling the operation of a controlled object on the basis of an error signal calculated from a target signal of the controlled object and an observation signal of the controlled object, a repetitive control unit sampling the error signal with a sampling clock pulse to obtain a repetitive signal component generated in synchronization with rotation of the disk medium from the sampled error signal, a sampling clock generation unit generating the sampling clock pulse and resetting a timing at which the sampling clock pulse is generated in accordance with a rotation detecting pulse and a sampling clock limit unit limiting generation of the sampling clock pulse at a timing immediately before generation of the rotation detecting pulse.

Disk device and disk drive controlling method

A solid immersion lens (SIL) is provided. The SIL includes a spherical part, a cone-shaped part, a tip part, and an edge part between the cone-shaped part and the tip part. The edge part includes a curved surface.

Solid immersion lens and focusing lens, optical pickup device, and data recording/reproducing apparatus using the same

An optical pickup apparatus includes a light source, focusing optics, a light detector, a controller, and a drive unit. The drive unit first drives the focusing optics to a specific position on an information recording medium. Light from the light source irradiates the information recording medium via the focusing optics as near-field light. Light reflected off the medium due to total internal reflection is then detected by the light detector, generating a gap error signal as a result. The controller then generates a gap servo signal by conducting a feed-forward control, whereby a push-pull signal in the direction orthogonal to the relative travel direction of the medium is applied to the gap error signal. In so doing, precise control of the gap size between the focusing optics and the information recording medium is achieved for near-field read/write operations.

Optical pickup apparatus, optical read/write apparatus, and gap control method

There is provided a servo controller that can automatically set a filter intended for stabilizing a closed loop. The servo controller includes a repetitive controller. The repetitive controller implements repetitive control of a servo error signal (observation signal y(t)) by producing, by an adaptive line spectrum enhancer or adaptive linear prediction unit, a second error signal (including mainly a rotational sync signal) resulted from reduction of an irrotational sync component from a first error signal resulted from subtraction of the observation signal y(t) from a target signal r(t) and producing a third error signal obtained by sequentially updating the first error signal while making one-period delay of the second error signal.

Servo control apparatus and method, and disk recording or playback apparatus

An optical pickup device is provided. The optical pickup device includes a light source, a focusing optical system configured to irradiate an optical recording medium with near-field light, a light-detecting unit configured to detect a total-reflection return-light quantity from the optical recording medium, a control unit configured to generate a control signal in response to a detection signal supplied from the light-detecting unit, and a drive unit configured to drive the focusing optical system to a predetermined position above the optical recording medium. The control unit feeds forward a push-pull signal in a traveling direction of the drive unit relative to the optical recording medium to a gap-error signal supplied from the light-detecting unit to generate a gap-servo signal. The control unit includes a repetitive controller storing a predetermined number of the push-pull signals.

Optical pickup device, optical recording/reproducing apparatus and gap-control method

An optical disk apparatus includes: a light source that emits laser light; an optical section including an objective lens group positioned in close proximity to an optical recording medium to generate near-field light from laser light emitted from the light source; a gap servo section configured to control a gap between the optical recording medium and the optical section on the basis of a return light quantity of the laser light via the optical section; a focus adjusting section configured to adjust focus of the near-field light radiated onto the optical recording medium of the optical section, in a state where gap servo is being performed by the gap servo section; and a gap servo correcting section configured to correct the gap servo by the gap servo section when focus of the near-field light is adjusted by the focus adjusting section.

Optical disk apparatus and servo control method

A beam spot position control device, for controlling multiple beam spot positions irradiated onto an optical recording medium so as to be disposed linearly, includes a light detecting unit for detecting the amount of return light for each of a plurality of beam spots disposed linearly, a tracking control unit for performing tracking control based on tracking error signals of at least one of the beam spots detected with the optical detecting unit, and a rotation control unit for rotating the plurality of beam spots which are disposed linearly, based on the DC offset amount of the tracking error signals of at least two of the beam spots detected with the optical detecting unit.

Beam spot position control device and beam spot position control method, and optical disk recording and reproducing device

An information recording and/or reproducing apparatus using a removable disk-shaped optical recording medium () is provided which includes a storage unit () to store an axial-runout amount in a predetermined radial position on the disk-shaped optical recording medium () being rotated, a near-field light projector () provided to condense a light beam emitted from a light source () and which projects the condensed light beam as near-field light when located in a field near the information recording surface of the disk-shaped optical recording medium (), a first controller () which multiplies an axial-runout amount read from the storage unit () by a predetermined gain to generate a control signal and controls the near-field light projector () to follow the axial-runout amount of the disk-shaped optical recording medium (), and a second controller () to control the near-field light projector () on the basis of the linear characteristic of the return-light amount of the near-field light to keep a predetermined distance in the near field from the information recording surface.

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Tokyo, Japan

Tsutomu Ishimoto