摘要:
Reproduction on an optical recording medium having plural information layers involves the problem of distortion occurring due to interlayer crosstalk and hence deterioration in the quality of a readout signal. At a predetermined radius, a correction coefficient for correcting the amount of fluctuation components is calculated from a readout signal with distortion due to the interlayer crosstalk, and then is stored. The stored correction coefficient is used to eliminate crosstalk components and to correct readout signal fluctuation during reproduction on a predetermined area. In this way, the original readout signal without interlayer crosstalk components can be obtained, so that good-quality reproduction characteristics can be achieved.
摘要:
Disclosed are an information recording method and an optical disk unit that maintain a good jitter even when a line velocity is variable in a mark edge system. In the case where an erasing power when erasing a record mark at a linear velocity v1 is Pe1(mW), a recording power when forming the record mark at the linear velocity v1 is Pw1(mW), an erasing power when erasing the record mark at a linear velocity v2 faster than v1 is Pe2(mW), and a power when forming the record mark at the linear velocity v2 is Pw2(mW), a relationship of Pw1/Pe1>Pw2/Pe2 is satisfied.
摘要:
A DVD recording method for recording data onto recording media by using a given coding rule, including: generating two data streams by using a plurality of code mapping variants prepared for coding input data, quasi-randomly selecting one of the plurality of code mapping variants, if absolute DSVs of the two data streams are substantially equal, and converting into recording code sequences, where polarities of said two data streams are inverted with respect to each other; and recording data onto said recording media, based on said recording code sequences.
摘要:
A test-write method for accurately and quickly determining recording conditions, and an apparatus suitable therefor. In a 2T-based strategy, recording pulse conditions are determined by separately test-writing an even-number length mark and an odd-number length mark, and then the relative positions of the even-number length mark and the odd-number length mark at the recording pulse start time are adjusted.
摘要:
An optical recording/reproducing method employs a recording laser beam having a first output and a first wavelength, and a reproducing laser beam having a second output lower than the first output and a second wavelength shorter than the first wavelength. A disk-like recording medium is irradiated with the recording and reproducing laser beams by use of an objective lens having an NA of about 0.55 so that a small mark equal to or smaller than about one fourth of a spot size optically defined from the wavelength of the recording laser beam and the NA of the objective lens is formed on the recording medium by a recording characteristic of the recording medium and a shielding plate provided in an optical system for irradiation with the laser beam. Two-dimensional recording is performed as a recording system to arrange marks at lattice points of a two-dimensional lattice which extend in a track direction and a track radius direction. The reproducing system detects a reproduction signal from the mark on the two-dimensional lattice point, and the reproduction signal from each mark is used to perform a signal processing, thereby detecting information.
摘要:
An optical recording/reproducing method employs a recording laser beam having a first output and a first wavelength, and a reproducing laser beam having a second output lower than the first output and a second wavelength shorter than the first wavelength. A disk-like recording medium is irradiated with the recording and reproducing laser beams by use of an objective lens having an NA of about 0.55 so that a small mark equal to or smaller than about one fourth of a spot size optically defined from the wavelength of the recording laser beam and the NA of the objective lens is formed on the recording medium by a recording characteristic of the recording medium and a shielding plate provided in an optical system for irradiation with the laser beam. Two-dimensional recording is performed as a recording system to arrange marks at lattice points of a two-dimensional lattice which extend in a track direction and a track radius direction. The reproducing system detects a reproduction signal from the mark on the two-dimensional lattice point, and the reproduction signal from each mark is used to perform a signal processing, thereby detecting information.
摘要:
An information recording method and device for recording information by irradiating an optical information recording medium with an energy beam includes forming a first recording mark by irradiation of a monopulse-shaped energy beam having at least a first power level and a second power level that is higher than the first power level, and forming a space succeeding the first recording mark with a write strategy having a downward pulse of a third power level that is lower than the first power level on a backside of a midpoint of the space.
摘要:
An information recording method of recording information with a high degree of accuracy on a semitransparent recording layer, which is subjected to severe thermal interference, of a multilayered recording medium. A downward pulse is applied to the back half portion of a prescribed space in the waveform of an energy beam used for irradiation when the space is formed. Thereby good recording performance is obtained.
摘要:
The object of the present invention is to provide a test writing method for seeking the optimum write power correctly and in a short time under a high speed recording condition in a test writing method and an information recording device for recording information by forming different marks from the unrecorded part by injecting energy onto the recording medium. To achieve the above object, even number length marks and odd number length marks are separately test written in the 2T strategy to seek the respective optimum write power. Due to the possibility of enhancing the precision of test writing, a good recording ability can be obtained.
摘要:
In forming a space layer of a multi-formation-layer recording medium, there are provided a medium having a high precision in a thickness of the space layer and its manufacturing process. In the multi-formation-layer recording medium wherein at least two pairs of an information recording layer and a translucency spacer are layered on a substrate having physical patterns composed of an optical spot groove and/or pits on the surface, an average thickness of the translucency spacers in an information zone is 15 μm or less, and a difference in spacer thickness between a minimum value and a maximum value is 2 μm or less.