Sony Corporation

Sony Corpotation

Shigeaki A Wachi

Tadao Suzuki

Tadao Yoshida

Hidetoshi Kamoto

Masashi Shiraishi

Dharam Pal Gosain

Masafumi Ata

Koji Kadono

Hisashi Kajiura

Ryuichiro Maruyama

Sumihiro Okawa

Houjin Huang

Tamotsu Yamagami

Tetsu Watanabe

Susumu Senshu

Tetsuji Kawashima

Eiji Kumagai

Susumu Tosaka

Fumihiko Yoshii

Shinichiro Kuwabara

Hiroyuki Shinkai

Hideki Inoue

Akashi Ito

A method of manufacturing a tubular carbon molecule capable of regularly aligning a carbon nanotube with a finer spacing is provided. A catalyst is arranged on a material substrate () made of a semiconductor such as silicon (Si) and including iron (Fe) as a catalyst through the use of melting according to a modulated heat distribution (). The heat distribution () is formed, for example, through diffracting an energy beam () by a diffraction grating (). As a method of arranging the catalyst, for example, iron may be deposited in a planar shape or a projection shape in a position corresponding to the heat distribution (), or the deposited iron may be used as a master to be transferred to another substrate. A carbon nanotube is grown through the use of the arranged catalyst. The grown carbon nanotube can be used as a recording apparatus, a field electron emission device, an FED or the like.

Method of manufacturing tubular carbon molecule and tubular carbon molecule, method of manufacturing recording apparatus and recording apparatus, method of manufacturing field electron emission device and field electron emission device, and method of manufacturing display unit and display unit

Method of manufacturing tubular carbon molecule and tubular carbon molecule, method of manufacturing field electron emission device and field electron emission device, and method of manufacturing display unit and display unit

A recording medium and technique which reduces problems relating to copyright, reduces the necessity for collecting an optical disk for, e.g., rental use and enables the optical disk itself to be inhibited from rental use. A reflectance of a reproducing film of the optical disk is changed by an irradiating laser beam having a greater strength than the laser beam strength used to form the film. The depth of a pre-pit in a data section is set to less than a quarter of the wavelength of the laser beam and the reproducing film is composed such that its reflectance drops if it is irradiated by the laser beam having the greater strength.

Optical disk capable of inhibiting from rental use

A magnetic modulator coil driving circuit comprises: first and second switching elements for inverting the polarity of exciting currents supplied to magnetic modulator coils, first and second bias voltage setting circuit for determining control voltages to be applied to the first and second switching elements to adjust the currents flowing through the first and second switching elements to a predetermined value, and a data input circuit for supplying modulating data to turn on and off the first and second switching elements alternately. The magnetic modulator coil driving circuit applies a control voltage to the control electrode of the corresponding switching element to control the exciting current to be supplied through the switching element to the corresponding magnetic modulator coil so that the exciting current coincides with a desired value when a reference voltage is applied to the control electrode. Thus a fixed exciting current is supplied to the magnetic modulator coil so that the intensity of the magnetic field may not vary due to temperature variation in the magnetic modulator coil and the magnetic modulator coil may not overheat or burn.

Temperature invariant, magneto-optic modulator coil driving circuit

Apparatus and method for reproducing data from a CD-ROM at a constant angular velocity and for recording and reproducing data to and from a magneto-optical compact disc (CD-MO) at a constant angular velocity. Data reproduced from the CD-ROM is demodulated in accordance with an amount of reproduction time of a sync signal contained in the reproduced data. The clock rate of data to be recorded to or reproduced from the CD-MO is determined in accordance with the position or zone on the CD-MO at which the data is to be recorded or from which it is reproduced. The position or zone may be identified by address data which is reproduced from the CD-MO. In addition, a constant rotational velocity of the CD-MO is maintained by measuring an amount of reproduction time of the address data and varying the rotational velocity of the CD-MO in accordance with the measured reproduction time.

Apparatus and method for adjusting a rotational velocity of a disk

A disk storage medium, for example, a magneto-optical compact disk, includes a plurality of data areas that have data stored therein and a plurality of address areas each associated with a respective data area and that have address data stored therein. The data in each of the data areas are stored at respectively different clock rates, and all of the address data in all of the address areas are stored at the same constant clock rate.

Optical disk capable of storing information data at difference clock

Apparatus and method for reproducing data from a record medium

An optical recording medium on which a data signal is formed comprises an area A of recording tracks for recording a data signal between pairs of grooves Gr and a d.c. offset cancel area B for canceling d.c. offset by the push-pull system, which serves as a predetermined area. In the d.c. offset cancel area B, no grove Gr is formed, and grooves are formed at the recording track center positions Tc. The groove at the recording track center position Tc is caused to have the same width and depth as those of the groove Gr. In carrying out recording/reproduction of a data signal by using this optical recording medium, a return light from the optical recording medium is detected by a bisected detector. A difference signal between outputs from the detector is determined by an amplifier. In accordance with an output signal of a sample-hold signal supply unit, first and second sample-hold units respectively hold signals having output phases different from each other by 180 degrees. An adder adds these signals to take out only a d.c. fluctuation component to eliminate the d.c. fluctuation component superimposed on a tracking error signal at a d.c. offset eliminating unit.

Optical recording medium and recording and/or reproducing apparatus

An optical recording medium on which a data signal is formed comprises an area A of recording tracks for recording a data signal between pairs of grooves Gr and a d.c. offset cancel area B for canceling d.c. offset by the push-pull system, which serves as a predetermined area. In the d.c. offset cancel area B, no grove Gr is formed, and grooves are formed at the recording track center positions Tc. The groove at the recording track center position Tc is caused to have the same width and depth as those of the groove Gr. In carrying out recording/reproduction of a data signal by using this optical recording medium, a return light from the optical recording medium is detected by a bisected detector. A difference signal between outputs from the detector is determined by an amplifier. In accordance with an output signal of a sample-hold signal supply unit, first and second sample-hold units respectively hold signals having output phases different from each other by 180 degrees An adder adds these signals to take out only a d.c. fluctuation component to eliminate the d.c. fluctuation component superimposed on a tracking error signal at a d.c. offset eliminating unit.

In a circuit and method for moving an optical pickup to a set target track on an optical disc, namely performing a track seek operation wherein, the address of a current track is detected with address information obtained from a playback signal from the optical disc, a reference value which is generated that chronologically changes while the optical pickup is being moved from the address of the current track to the address of the target track, an actuator for moving the optical pickup in the radial direction of the optical disc being driven so as to perform the seek operation at a high speed without requiring a speed sensor for sensing the speed of the moving optical pickup.

Seek circuit for optical disc

An optical pickup is controlled to move to a target track on an optical information storage disc based on target value information representing the sum of speed information indicative of a speed at which the optical pickup is to move, and distance information indicative of a distance which the optical pickup has moved toward the target track. A first subtractor produces a differential signal indicative of the difference between the target value information and remaining distance information which represents a remaining distance that the optical pickup is to move. The differential signal is supplied to a second subtractor which determines the difference between the differential signal and actual speed information indicating an actual speed at which the optical pick is moving. The second subtractor produces a differential signal which is supplied to an actuator to move the optical head.

Seek control for information storage disc drive

A focus servo device for use in an optical disk apparatus including a reproducer for irradiating a light beam emitted from a light source to an optical disk through an objective lens, and detecting an RF signal and a focus error signal on the basis of the return light beam reflected from the optical disk; a maximum-minimum detector for detecting the maximum and the minimum of the RF signal obtained from the reproducer; and a control signal generator for generating a focus servo signal obtained from the reproducer responsive to the maximum and the minimum of the RF signal detected by the maximum-minimum detector. Since the focus servo lock-in control is performed in conformity with the detected maximum and minimum values of the reproduced RF signal, the apparatus is capable of recording information on and/or reproducing the same from any optical disk regardless of the disk's reflectivity.

System for calculating focus servo control signal using focus error

An optical recording and reproducing apparatus comprising an erroneous recording prevention component which prevents this apparatus from making an erroneous recording or erasing operation while it records data on a writable disk. The apparatus is arranged such that, while it is performing a recording or erasing operation, a state of its beam of light just about to go off the control point of tracking and a state of its beam of light just about to go off the control point of focusing are each monitored and, when either of the states is detected, the recording or erasing operation is canceled. Hence, laser power of the beam of light can be controlled before the beam of light completely goes off the control point of tracking, thereby preventing the beam of light from affecting data having been recorded along other tracks.

Optical recording and reproducing apparatus that cancels recording or

A spindle servo system for a magneto-optical recording/playback apparatus, comprising a PLL circuit lockable in phase by sample servo pits formed on a track of a magneto-optical disc; a phase comparator for comparing the phase of a signal, whose period corresponds to the output of the PLL circuit, with the phase of a reference frequency signal; and a resonator having a reference frequency conforming to the eccentricity cycle of the disc. In this servo system, the rotation period of a spindle motor for driving the disc is controlled in accordance with the output of the phase comparator and the output of the resonator. The PLL circuit includes a voltage-controlled crystal oscillator, and the resonator is excited in conformity to the output of the phase comparator to control the rotation frequency of the spindle motor, thereby reducing the jitter component included in the output of the PLL circuit.

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Tokyo, Japan

Shigeaki A Wachi