Abstract: Provided are an optical information recording/reproducing apparatus and method capable of managing a wavelength of a light source when information is recorded/reproduced by utilizing holography, and limiting a wavelength of an interference fringe in a medium, and an optical information recording medium. For information recording/reproducing relative to an optical information recording medium by a pickup, a wavelength detector circuit detects a reference wavelength recorded in a storage area of the optical information recording medium, in accordance with the detected reference wavelength, a controller adjusts a wavelength of a light source of the pickup to have an optimum wavelength, and if a temperature detected with a temperature sensor indicates a predetermined change, readjusts the wavelength of the light source of the pickup to have an optimum wavelength.

Abstract: An optical disk apparatus is provided that has a signal processing circuit for equalizing a signal so as to achieve predetermined equalization, in which interference between codes is permitted, by means of an adaptive equalization circuit or the like, and for performing binarization by means of a maximum likelihood decoding circuit in which interference is performed as a rule, and thereby achieves stabilized signal reproduction in a narrow-band transmission. When evaluating the quality of the recorded signal through the use of the recording parameter learning and the reproduction system such as recorded signal verification, the optical disk recording apparatus is capable of highly precisely evaluating the quality of the recorded signal by fixing a circuit characteristic after suspending the optimization operation of the adaptive equalization circuit or the like for optimizing the characteristic by the reproduced signal. An optical disk recording method is also provided.

Abstract: A recording and/or reproducing apparatus includes a plurality of devices in which a first device has a connecting unit connected with a host device to perform a data transfer with the host device, a second device shares a temporarily recording area with the first device to perform the data transfer between the first and second devices via the temporarily recording area, and the data transfer is performed by using the temporarily recording area shared with the first device and using the connecting unit of the first device when the second device performs the data transfer with the host device, in this way, a power consumption is reduced.

Abstract: A storage system having a plurality of optical disc devices allows other optical disc devices inside the storage system to reproduce the optical disc recorded by a certain optical disc device but inhibits optical disc devices outside the storage system to reproduce the optical disc. A device key as a base for generating an encryption key is common to the plurality of optical disc devices. In the optical disc devices, a guest key other than the device key can be used temporarily to generate the encryption key. An authentication list containing a reproduction condition is recorded with the key information to the optical disc.

Abstract: A recording and/or reproducing apparatus includes a plurality of devices in which a first device has a connecting unit connected with a host device to perform a data transfer with the host device, a second device shares a temporarily recording area with the first device to perform the data transfer between the first and second devices via the temporarily recording area, and the data transfer is performed by using the temporarily recording area shared with the first device and using the connecting unit of the first device when the second device performs the data transfer with the host device, in this way, a power consumption is reduced.

Abstract: Provided are an optical information recording/reproducing apparatus and method capable of managing a wavelength of a light source when information is recorded/reproduced by utilizing holography, and limiting a wavelength of an interference fringe in a medium, and an optical information recording medium. For information recording/reproducing relative to an optical information recording medium by a pickup, a wavelength detector circuit detects a reference wavelength recorded in a storage area of the optical information recording medium, in accordance with the detected reference wavelength, a controller adjusts a wavelength of a light source of the pickup to have an optimum wavelength, and if a temperature detected with a temperature sensor indicates a predetermined change, readjusts the wavelength of the light source of the pickup to have an optimum wavelength.

Abstract: Quantization noise due to analog-to-digital conversion may be larger than a noise component of an input signal, and therefore sufficient performance may not be obtained.

Abstract: The present invention aims to, when recording pulse information are transmitted to a laser driver lying over a pickup through an optical disk, reduce the number of transmission paths or lines from a conventional transmission method and avoid degradation of recording performance due to transmission path characteristics upon fastening of a recording speed thereby to provide stable recording performance at high-speed recording. The invention of the present application reduces the number of transmission signals by encoding multi-level laser pulse information transmitted by the laser driver. Further, gray codes are used for encoding to reduce constraints of skew between bits. Furthermore, encoding is executed using each state transition and the state transitions are switched according to each recording mark and space, thereby reducing the occurrence of a short pulse on each transmission path.

Abstract: An optical disk apparatus is provided that has a signal processing circuit for equalizing a signal so as to achieve predetermined equalization, in which interference between codes is permitted, by means of an adaptive equalization circuit or the like, and for performing binarization by means of a maximum likelihood decoding circuit in which interference is performed as a rule, and thereby achieves stabilized signal reproduction in a narrow-band transmission. When evaluating the quality of the recorded signal through the use of the recording parameter learning and the reproduction system such as recorded signal verification, the optical disk recording apparatus is capable of highly precisely evaluating the quality of the recorded signal by fixing a circuit characteristic after suspending the optimization operation of the adaptive equalization circuit or the like for optimizing the characteristic by the reproduced signal. An optical disk recording method is also provided.

Abstract: The present invention has an object to stably reproduce wobble signals of all disks of CD-R/RW, DVD-R/RW and DVD-RAM by one wobble signal reproducing circuit. In the wobble signal reproducing circuit, an AGC (AUTOMATIC GAIN CONTROL) circuit for equating a push-pull circuit output of a wide range and an RF amplitude of an optical detector output of two systems obtained by push-pull, and an AGC (AUTOMATIC GAIN CONTROL) circuit for making a wobble amplitude uniform are provided with a function to hold a gain or to change over a response time constant, and at the time of reproduction of the DVD-R/RW, a land pre-pit region is detected by the push-pull output to hold AGC (AUTOMATIC GAIN CONTROL) or change over a response time constant. Besides, in an address information recording region (PID region) at the time of reproduction of the DVD-RAM, the AGC (AUTOMATIC GAIN CONTROL) is held or the response time constant is changed over.

Abstract: A laser driver drives a laser diode by producing a write strategy, that is, a recording waveform from a recording clock and a modulated signal. In one embodiment, a laser driver produces the waveform of a driving signal, which is used to drive a laser diode, using a record data signal that represents record data to be recorded on a recording medium. The laser driver comprises an internal clock production circuit that produces an internal clock synchronous with the record data signal, and a strobe circuit that strobes the record data signal according to the internal clock.

Abstract: The present invention has an object to stably reproduce wobble signals of all disks of CD-R/RW, DVD-R/RW and DVD-RAM by one wobble signal reproducing circuit. In the wobble signal reproducing circuit, an AGC (AUTOMATIC GAIN CONTROL) circuit for equating a push-pull circuit output of a wide range and an RF amplitude of an optical detector output of two systems obtained by push-pull, and an AGC (AUTOMATIC GAIN CONTROL) circuit for making a wobble amplitude uniform are provided with a function to hold a gain or to change over a response time constant, and at the time of reproduction of the DVD-R/RW, a land pre-pit region is detected by the push-pull output to hold AGC (AUTOMATIC GAIN CONTROL) or change over a response time constant. Besides, in an address information recording region (PID region) at the time of reproduction of the DVD-RAM, the AGC (AUTOMATIC GAIN CONTROL) is held or the response time constant is changed over.

Abstract: Quantization noise due to analog-to-digital conversion may be larger than a noise component of an input signal, and therefore sufficient performance may not be obtained.

Abstract: The present invention has an object to stably reproduce wobble signals of all disks of CD-R/RW, DVD-R/RW and DVD-RAM by one wobble signal reproducing circuit. In the wobble signal reproducing circuit, an AGC (AUTOMATIC GAIN CONTROL) circuit for equating a push-pull circuit output of a wide range and an RF amplitude of an optical detector output of two systems obtained by push-pull, and an AGC (AUTOMATIC GAIN CONTROL) circuit for making a wobble amplitude uniform are provided with a function to hold a gain or to change over a response time constant, and at the time of reproduction of the DVD-R/RW, a land pre-pit region is detected by the push-pull output to hold AGC (AUTOMATIC GAIN CONTROL) or change over a response time constant. Besides, in an address information recording region (PID region) at the time of reproduction of the DVD-RAM, the AGC (AUTOMATIC GAIN CONTROL) is held or the response time constant is changed over.

Abstract: An optical disk unit includes a pick-up component to read information stored on an optical disk provided within the disk unit and generate a reproduction signal corresponding to the information that has been read, the optical disk having a synchronization pull-in pattern region and a data region; an equalization circuit to receive the reproduction signal from the pick-up component and output an equalized signal corresponding to the reproduction signal received from the pick-up component; and a phase lock loop (PLL) circuit for generating a reproduction clock signal that is synchronized to the reproduction signal.

Abstract: A method and apparatus for recording information which presume a recording state from reflected light during recording to achieve a stable recording quality. When recording information on an optical disk by irradiating laser light with a specified record power (Pw) to form a train of record pits, the recording is performed while forcing a value (CF) of B/Pw2 to be kept substantially constant, where B is the value obtainable by sample-hold of a reflection light amount upon irradiation of the laser light with the specified record power (Pw). Performing the recording in this way makes it possible to realize the recording quality with increased stability. In addition, upon alteration of a tilt angle, arithmetic processing is redone to thereby achieve the stability-enhanced recording quality.

Abstract: A laser driver drives a laser diode by producing a write strategy, that is, a recording waveform from a recording clock and a modulated signal. In one embodiment, a laser driver produces the waveform of a driving signal, which is used to drive a laser diode, using a record data signal that represents record data to be recorded on a recording medium. The laser driver comprises an internal clock production circuit that produces an internal clock synchronous with the record data signal, and a strobe circuit that strobes the record data signal according to the internal clock.

Abstract: The present invention has an object to stably reproduce wobble signals of all disks of CD-R/RW, DVD-R/RW and DVD-RAM by one wobble signal reproducing circuit. In the wobble signal reproducing circuit, an AGC (AUTOMATIC GAIN CONTROL) circuit for equating a push-pull circuit output of a wide range and an RF amplitude of an optical detector output of two systems obtained by push-pull, and an AGC (AUTOMATIC GAIN CONTROL) circuit for making a wobble amplitude uniform are provided with a function to hold a gain or to change over a response time constant, and at the time of reproduction of the DVD-R/RW, a land pre-pit region is detected by the push-pull output to hold AGC (AUTOMATIC GAIN CONTROL) or change over a response time constant. Besides, in an address information recording region (PID region) at the time of reproduction of the DVD-RAM, the AGC (AUTOMATIC GAIN CONTROL) is held or the response time constant is changed over.

Abstract: The present invention has an object to stably reproduce wobble signals of all disks of CD-R/RW, DVD-R/RW and DVD-RAM by one wobble signal reproducing circuit. In the wobble signal reproducing circuit, an AGC (AUTOMATIC GAIN CONTROL) circuit for equating a push-pull circuit output of a wide range and an RF amplitude of an optical detector output of two systems obtained by push-pull, and an AGC circuit for making a wobble amplitude uniform are provided with a function to hold a gain or to change over a response time constant, and an address information recording region (PID region) at the time of reproduction, the AGC (AUTOMATIC GAIN CONTROL) is held or the response time constant is changed over.

Abstract: The present invention has an object to stably reproduce wobble signals of all disks of CD-R/RW, DVD-R/RW and DVD-RAM by one wobble signal reproducing circuit. In the wobble signal reproducing circuit, an AGC (AUTOMATIC GAIN CONTROL) circuit for equating a push-pull circuit output of a wide range and an RF amplitude of an optical detector output of two systems obtained by push-pull, and an AGC (AUTOMATIC GAIN CONTROL) circuit for making a wobble amplitude uniform are provided with a function to hold a gain or to change over a response time constant, and at the time of reproduction of the DVD-R/RW, a land pre-pit region is detected by the push-pull output to hold AGC (AUTOMATIC GAIN CONTROL) or change over a response time constant. Besides, in an address information recording region (PID region) at the time of reproduction of the DVD-RAM, the AGC (AUTOMATIC GAIN CONTROL) is held or the response time constant is changed over.