摘要:
In a storage device, a bad-sector detecting unit detects a bad sector, and a process determining unit determines whether rescue process is performed for the bad sector. Upon determining to perform the rescue process, the process determining unit controls a damping ratio. A table-updating control unit records various information in an alternating-process control table, and a controller records and reproduces data with respect to a rescue sector based on the alternating-process control table.
摘要:
An optical information recording medium having a plurality of grooves and a plurality of lands alternately formed, where each groove and each land function as recording tracks. The medium includes a first header region having a plurality of first phase pits respectively formed on extensions of the plurality of lands, and a second header region having a plurality of second phase pits respectively formed on extensions of the plurality of grooves. Each groove has an optical depth of about 3&lgr;/8, where &lgr; is the wavelength of a light beam to be used. Each first phase pit has an optical depth that is smaller than that of each groove. Each second phase pit has an optical depth that is substantially equal to that of each groove. The first header region and the second header region are shifted from each other along the extension of each groove.
摘要:
An optical storage unit which uses a light beam to record information on and/or reproduce information from a recording medium. The recording medium is provided with at least one land and at least one groove, and information is recorded in plural sectors in each of the land(s) and groove(s). The optical storage unit includes an optical phase adjuster for adjusting a phase of a polarization component of the light beam reflected from the recording medium based on a track type determination of a target address. An optical pickup is provided for reproducing information recorded on the recording medium using the phase-adjusted polarization component of the light beam.
摘要:
Disclosed is an optical storage device for reading information from an optical storage medium by an optical head. The optical storage device comprises an optical head including a track actuator for scanning on the skew across tracks on the optical storage medium by the laser beam, and a divided-by-4 light receiving unit for receiving the laser beam from the optical storage medium, a moving motor for moving the optical head, a first signal processing unit for calculating a track error signal on the basis of an output of the divided-by-4 light receiving unit, a second signal processing unit for calculating a shift signal of the objective lens from the output of the divided-by-4 light receiving unit, and a control unit for controlling the track actuator or the moving motor by the track error signal, and controlling the track actuator or the moving motor so that the laser beam passing through the objective lens is located at the center of the objective lens. With this construction, a lens position can be detected, and hence a lens position sensor becomes unnecessary.
摘要:
An optical information recording medium having a plurality of grooves and a plurality of lands alternately formed, where each groove and each land function as recording tracks. The medium includes a first header region having a plurality of first phase pits respectively formed on extensions of the plurality of lands, and a second header region having a plurality of second phase pits respectively formed on extensions of the plurality of grooves. Each groove has an optical depth of about 3 &lgr;/8, where &lgr; is the wavelength of a light beam to be used. Each first phase pit has an optical depth that is smaller than that of each groove. Each second phase pit has an optical depth that is substantially equal to that of each groove. The first header region and the second header region are shifted from each other along the extension of each groove.
摘要:
An optical information storage unit is provided with a light source, a polarization beam splitter reflecting and irradiating a bundle of rays emitted from the light source onto a recording surface of a recording medium, and an optical element receiving a convergent light reflected by the recording surface and passed through the polarization beam splitter, and having an infinite focal distance with a convergent point of the convergent light that is variable.
摘要:
A magneto optical disc system includes a disc having permanently recorded tracks overlain with magneto optical recording material. Data is recorded in the magneto optical material in tracks superimposed over the permanently recorded tracks, using the read-only data to define magneto optical tracks. The magneto optically recorded data is correlated with the prerecorded data for defining the location of data stored in the magneto-optic tracks.
摘要:
A mobile body obtains information from an in-vehicle sensor related to the operating condition and obtains information from a navigation system as correlated information. Application software is introduced to a portable information equipment at the time of signing up for a contract for receiving a service of the present service provision system when purchasing the mobile body. A user terminal is permitted to install various kinds of application software provided by a service provision entity, and information stored in the portable information equipment is got in the terminal by linking therewith. The service provision entity receives and analyzes the information got in the user terminal and provides a service including a diagnosis of the mobile body.
摘要:
A security system of the present invention using an optical information recording medium allowing concurrent reading out of ROM-RAM information, is able to receive data from the optical information recording medium having an identification symbol recording region recording an identification symbol identifying the medium, a ROM region recording plain text data, and a magneto-optical recording film formed in a region corresponding to the ROM region, the magneto-optical recording film recording encrypted data of the plain text data, the security system being configured such that the recording medium recording a decryption program for decrypting the encrypted data is usable, the security system comprising a reception unit for receiving the encrypted data in response to a data transmission request that conforms to the identification symbol identifying the optical information recording medium; a recording unit for recording in the recording medium the encrypted data received from the reception unit; and a decryption unit for decrypting with the decryption program the encrypted data recorded in the recording medium.
摘要:
An optical information storage unit for reproducing information recorded on a magneto-optic recording medium having a land and a groove as recording tracks, is provided with at least one of first and second systems, where the first system includes a 1/2 wave plate which is arranged so that a crystal optical axis of the 1/2 wave plate and an electrical vector of a light beam emitted from a light source forms approximately 45 degrees, where the 1/2 wave plate being removable from a position of the light beam, and the second system is arranged with the 1/2 wave plate so that the crystal optical axis of the 1/2 wave plate and the electrical vector of the light beam emitted from the light source forms approximately 45 degrees, where the 1/2 wave plate is movable so that another 1/2 wave plate can move to the position of the light beam so that a crystal optical axis of the other 1/2 wave plate is parallel to or perpendicular to the electrical vector. An electrical vector of the light beam irradiated on the magneto-optic recording medium is set so that the electrical vector is perpendicular to a direction in which a recorded signal flows when reproducing the signal from the land and is parallel to the direction in which the recorded signal flows when reproducing the signal from the groove.