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 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.
摘要:
An optical information storage unit for irradiating a light on a recording medium which has a recording surface with a land and a groove, and detecting a reproduced signal from a reflected light received from the recording medium, is constructed to include a first optical element separating the reflected light received from the recording medium into at least three bundles of rays, a second optical element compensating phases of the bundles of rays separated by the first optical element, and a third optical element detecting polarization states of the bundles of rays separated by the first optical element. An amount of phase compensation made by the second optical element is such that an absolute value of a difference between an amount of phase compensation required to reproduce a signal from the land and an amount of phase compensation required to reproduce a signal from the groove is greater than or equal to 60.degree. but less than or equal to 180.degree..
摘要:
A system for reducing crosstalk in an optical scanning device for recording and reading optical data and magneto-optical data arranged in tracks of a recording medium includes a source for providing two light beams which are scanned along the tracks. The light beams are polarized in two polarization directions, are focused onto one of the tracks and are separated by a predetermined distance along the direction of the tracks, when incident on the tracks. Reflected light from the recording medium is focused onto first and second pairs of sensors. The difference of the signals from the first pair of sensors is compared with a delayed version of the difference of the signals from the second pair of sensors to provide a further signal representing magneto-optically recorded data. Signals from a first sensor of each pair of sensors may be summed to detect optically recorded data. One of the sensors of one pair of sensors may be realized as a four quadrant detector to provide conventional tracking and focusing error signals.