Pioneer Corporation

Hiroyuki Uchino

Yoshio Sasaki

Shogo Miyanabe

Kunihiko Horikawa

Eiji Muramatsu

Shoji Taniguchi

Akira Shirota

Yasuhiko Tominaga

Masatoshi Adachi

Hidenori Nakagawa

Hiroyuki Tanaka

Hisao Tanaka

Tadashi Ueda

Masakazu Furukawa

An information reproducing apparatus () is provided with: an offset adding device (--) for adding an offset value (OFS) which can be set to be variable, to a read signal (R) read from a recording medium (); a correcting device () for correcting waveform distortion occurring in a read signal corresponding to a long mark, of the read signal to which the offset value is added; and a waveform equalizing device () for performing a waveform equalization process on the read signal in which the waveform distortion is corrected.

Apparatus, method and program for waveform equalization on a read signal obtained by reading the record data recorded on a recording medium

An information reproducing apparatus () is provided with: a judging device () for judging whether or not a read signal (R) read from a recording medium () satisfies a desired reproduction property; a correcting device () for correcting waveform distortion occurring in a read signal corresponding to a long mark, of the read signal if it is judged that the read signal does not satisfy the desired reproduction property; and a waveform equalizing device () for performing a waveform equalization process on the read signal in which the waveform distortion is corrected.

Information reproducing apparatus and method, and computer program

An information reproducing apparatus () is provided with: a waveform shaping device () for performing waveform shaping on a read signal (R) read from a recording medium (), on the basis of a reference amplification factor; a correcting device () for correcting waveform distortion occurring in a read signal corresponding to at least a long mark, of the read signal on which the waveform shaping is performed; and a waveform equalizing device () for performing a waveform equalization process on the read signal in which the waveform distortion is corrected, the waveform shaping device arbitrarily increases the reference amplification factor.

An information reproducing apparatus () is provided with: a correcting device () for correcting waveform distortion occurring in a read signal corresponding to a long mark, of a read signal (R) read from a recording medium (); and a processing device () for performing a PRML (Partial Response Maximum Likelihood) process on the read signal in which the waveform distortion is corrected.

Device and method for reproducing information, and computer program

An information reproducing apparatus () is provided with: an offset adding device (--) for adding a first offset value (OFS) which can be set to be variable, to a read signal (R) read from a recording medium (); a correcting device () for correcting waveform distortion occurring in a read signal corresponding to a long mark, of the read signal to which the first offset value is added; an offset subtracting device (--) for subtracting a second offset value (OFS) which can be set to be variable, from the read signal in which the waveform distortion is corrected; and a waveform equalizing device () for performing a waveform equalization process on the read signal in which the second offset value is subtracted.

An information reproducing apparatus () is provided with: a correcting device () for correcting waveform distortion occurring in a read signal corresponding to a long mark, of read signal (R) read from a recording medium (); an amplitude limiting device () for limiting an amplitude level of the read signal in which the waveform distortion is corrected, by a predetermined amplitude limit value (L, &#x2212;L), thereby obtaining an amplitude limit signal; and a filtering device () for performing a high-frequency emphasis filtering process on the amplitude limit signal, thereby obtaining an equalization-corrected signal.

A recording apparatus includes: a first calculating device for calculating an optimum power for recording the data pattern into a recording-scheduled area (RSA) in an inner area; a first controlling device recording the data pattern with the optimum power outside an end on an outer side of the RSA; a second calculating device calculating an adjustment power used in adjusting a recording condition outside the end on the outer side of the RSA, considering a difference between recording sensitivity inside and outside the RSA; a second controlling device recording the data pattern for adjusting the recording condition with the adjustment power outside the RSA; a reading device obtaining a read signal; a measuring device measuring read signal jitter; an adjusting device adjusting the recording condition for satisfactory jitter; and a third controlling device to record the data pattern into the RSA using the optimum power and the adjusted recording condition.

Recording apparatus and method, computer program, and recording medium

A recording apparatus includes: a first strategy calculating device (SCD) for calculating a first optimum strategy allowing jitter recorded at a first speed to satisfy a desired condition by adjusting a first standard strategy; a second SCD for calculating a second standard strategy at a second speed by performing clock cycle conversion according to a difference between the first and second speeds on the first standard strategy; a second power calculating device for calculating a second optimum power used at the second speed; a third SCD for calculating a second optimum strategy allowing jitter recorded at the second speed to satisfy a desired condition, by adjusting the second standard strategy; and a fourth SCD for calculating a third optimum strategy at a third speed, based on each of a difference between the first standard and optimum strategies and a difference between the second standard and optimum strategies.

Recording device and method, and computer program, and recording medium

A recording apparatus () is provided with: a recording device () for recording a data pattern onto a recording medium (); a first controlling device () for stopping the recording; a reading device () for reading the data pattern which is recorded immediately before the recording is stopped, thereby obtaining a read signal; a measuring device () for measuring jitter of the read signal; an adjusting device () for adjusting a recording condition such that the jitter satisfies a desired condition, and a second controlling device () for restarting the recording of the data pattern by using the adjusted recording condition.

Recording device and method, computer program, and recording medium

An information recording apparatus () is for forming a record mark corresponding to a recording signal by applying a laser beam to a recording medium, and is provided with: a light source () for emitting the laser beam; and a signal generating device () for generating a recording pulse signal for driving the light source on the basis of the recording signal, the recording pulse signal includes a mark period and a space period, a level of the recording pulse signal corresponds to a recording power by which waveform distortion is greater than or equal to an upper limit (L) or is less than or equal to a lower limit (&#x2212;L) of an amplitude limit value on a limit equalizer (), in the mark period corresponding to a long mark.

Information recording apparatus and method, and computer program

In the information recording apparatus, by driving the light source by the pulse signal corresponding to the recording signal, the laser pulse corresponding to the recording signal is irradiated onto the recording medium. The recording signal has the mark period to form the recording mark, and the space period in which the recording mark is not formed. In the mark period, the output level of the laser pulse changes between the normal level and the writing level, thereby, the recording mark is formed on the recording medium. On the one hand, over a predetermined period in the space period, the output level of the laser pulse is changed to the low level lower than the normal level. Thereby, the heat accumulation onto the recording medium, due to the transient response of the laser pulse in the mark period, is reduced, and in the mark period after that, the correct recording mark can be formed.

Information recording apparatus and information recording method

Based on actual recording power information obtained during test writing, a recording power is efficiently controlled with high accuracy during actual recording. An information recording apparatus irradiates a laser light onto an information recording medium such as an optical disc to record data and reproduce the recorded data. In recording actual data such as data designated by a user, the information recording apparatus temporarily stops recording at the time when predetermined amount of data is recorded, and confirms recording quality. Namely, the apparatus reproduces the recorded data and determines the recording quality based on the reproduced data. When it is determined that the recording quality is within an appropriate range, the recording of the actual data is continued at the recording power. Meanwhile, when it is determined that the recording quality is out of the appropriate range, the recording power is corrected so that the recording quality becomes within the appropriate range, and the actual data is recorded. Thereby, even when the optimum recording power is changed due to some causes and condition change after recording start of the actual data, the recording power can be correspondently corrected, and accurate information recording with the appropriate recording power can be realized.

Information recording device, information recording method, and information recording program

An information recording device, an information recording method, and an information recording program capable of recording information with an appropriate modulation degree, a high asymmetry, and small waveform distortion. The information recording device applies a laser beam to a recording medium such as a DVD-R/RW and DVD+R/RW and forms a recording mark corresponding to a recording signal, thereby recording information. A recording pulse signal for forming the recording mark corresponding to the recording signal has a mark period for forming the recording mark and a space period not forming the recording mark. In test recording performed prior to actual information recording, a long mark recording power is kept constant while a short mark recording power is changed. Preferably, the short mark recording power in the test write is changed so that the asymmetry and/or the beta value is a value within a desired range.

An information recording device and method capable of forming a recording mark by suppressing thermal interference. The device applies a laser beam to a recording medium and forms a recording mark in accordance with a recording signal. The device includes a light source for emitting the laser beam, signal generation elements for generating a recording pulse signal according to the recording signal, and drive elements for driving the light source according to the recording pulse signal. The recording pulse signal has a mark period for forming the recording mark and a space period. The recording pulse signal makes the level in the entire space period equal to or shorter than a predetermined length and a part of the space period longer than the predetermined length to be off level. While the recording pulse signal is off level, the recording medium is cooled down, thereby suppressing the affect of thermal interference.

Information recording device and information recording method

An information recording apparatus () is provided with: a recording device () for irradiating an information recording medium () with laser light and for recording information onto the information recording medium; an obtaining device () for obtaining at least one of (i) a special OPC strategy for defining a waveform of the laser light used to calculate an optimum laser power of the laser light for recording the information at a second recording speed different from a first recording speed, at the first recording speed, and (ii) a recording strategy for defining a waveform of the laser light used to record the information at the second recording speed; a power calculating device () for calculating the optimum laser power by using the special OPC strategy at the first recording speed; and a controlling device () for controlling said recording device to record the information at the second recording speed, by using the calculated optimum laser power and the recording strategy.

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Tokorozawa, Japan

Hiroyuki Uchino