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AssigneeKabushiki Kaisha Toshiba
InventorsKazuyo UMEZAWA, Seiji Morita, Koji Takazawa, Naomasa Nakamura, Naoki Morishita, Shinichi Katsuda
Estimating the term…
According to one embodiment, an information recording medium has a plurality of recording layers, and records and reproduces information by using a semiconductor layer of 450 nm or less. When reproducing information, letting x be the frequency of repetitive recording of a shortest mark length and shortest space length of the information, the ratio of the value of a highest level to the value of a level at x/190 of a sum signal detected within the frequency range of x/3240 to x/190 is lower than 32 dB, or the ratio of the average value of the amplitudes of signals of repetitive recording of the shortest mark length and shortest space length to the value of the highest level within the frequency range of x/3240 to x/190 is higher than 10 dB.
An optical recording medium comprising a plurality of recording layers configured to record or reproduce information using light with a predetermined wavelength, wherein
A method of recording information on an optical recording medium comprising a plurality of recording layers configured to record or reproduce the information using light with a predetermined wavelength, wherein a period of channel clocks used to record at least one recording mark on the recording layer is assumed to be T, the information is recordable on the recording mark with a length of 2T, 3T, or more, multi-pulses are used to record the recording mark with the length of 3T or more, the multi-pulses includes a last pulse at an end thereof, and the recording mark with the length of 3T or more is recorded provided that a width of the last pulse falls within a range from 0T to 1.10, the method comprising:
A method of reproducing information from an optical recording medium comprising a plurality of recording layers on which the information is at least partly recorded using light with a predetermined wavelength, wherein a period of channel clocks used to record at least one recording mark on the recording layer is assumed to be T, the information is recordable on the recording mark with a length of 2T, 3T, or more, multi-pulses are used to record the recording mark with the length of 3T or more, the multi-pulses includes a last pulse at an end thereof, and the recording mark with the length of 3T or more is recorded provided that a width of the last pulse falls within a range from 0T to 1.10, the method comprising:
A disc drive for reproducing information from an optical recording medium comprising a plurality of recording layers on which the information is at least partly recorded using light with a predetermined wavelength, wherein a period of channel clocks used to record at least one recording mark on the recording layer is assumed to be T, the information is recordable on the recording mark with a length of 2T, 3T, or more, multi-pulses are used to record the recording mark with the length of 3T or more, the multi-pulses includes a last pulse at an end thereof, and the recording mark with the length of 3T or more is recorded provided that a width of the last pulse falls within a range from 0T to 1.10, the disc drive comprising:
Dependencies are inferred from the claim text.