Information recording method and apparatus

An information recording method for recording a sequence of sync frames, indicative of data, onto tracks of an optical recording medium in which prepits are formed on lands between the tracks at given intervals, and in which sync patterns, providing synchronization on a sync-frame basis, are inserted in the sync frames such that each sync pattern has a length in a track direction larger than a length of one of the prepits and a position of each sync pattern matches with a position of at least one of the prepits, the information recording method comprising the steps of:

• selecting codes that represent first sync patterns for a portion of the sync frames such that each first sync pattern is formed as a space on the recording medium, and selecting codes that represent second sync patterns for the remainder of the sync frames such that each second sync pattern is formed on the recording medium so as to meet a low-frequency reduction scheme;
• generating modulation codes based on the sync frames in which the selected codes are inserted, by modulating the sync frames containing the selected codes in accordance with a predetermined modulation scheme;
• generating a sequence of recording pulses by converting the modulation codes through a predetermined conversion scheme;
• and
• detecting a prepit position signal from one of the prepits for each of the sync frames during the writing of the recording pulses to the recording medium, so that a write position control is performed based the detected prepit position signal.

An information recording method for recording a sequence of sync frames, indicative of data, onto tracks of an optical recording medium in which prepits are formed on lands between the tracks at given intervals, and in which sync patterns, providing synchronization on a sync-frame basis, are inserted in the sync frames such that each sync pattern has a length in a track direction larger than a length of one of the prepits and a position of each sync pattern matches with a position of at least one of the prepits, the information recording method comprising the steps of:

• providing the prepits which are formed on the lands of the recording medium at intervals that are equal to an integral multiple of a unit length corresponding to a channel bit;
• selecting codes that represent first sync patterns for a portion of the sync frames such that each of the first sync patterns is formed as a space on the recording medium, when positions of the first sync patterns match with positions of the prepits, and selecting codes that represent second sync patterns for the remainder of the sync frames such that each of the second sync pattern is formed on the recording medium so as to meet a low-frequency reduction scheme, when positions of the second sync patterns do not match with the positions of the prepits;
• generating modulation codes based on the sync frames in which the selected codes are inserted, by modulating the sync frames containing the selected codes in accordance with a predetermined modulation scheme;
• generating a sequence of recording pulses by converting the modulation codes through a predetermined conversion scheme;
• and
• detecting a prepit position signal from one of the prepits for each of the sync frames during the writing of the recording pulses to the recording medium, so that a write position control is performed based the detected prepit position signal.

An information recording method for recording a sequence of sync frames, indicative of data, onto tracks of an optical recording medium in which prepits are formed on lands between the tracks at given intervals, and in which sync patterns, providing synchronization on a sync-frame basis, are inserted in the sync frames such that each sync pattern has a length in a track direction larger than a length of one of the prepits and a position of each sync pattern matches with a position of at least one of the prepits, the information recording method comprising the steps of:

• selecting codes that represent first sync patterns for a portion of the sync frames such that each of the first sync patterns is formed as a space, when the number of the first sync patterns being successively formed as a mark, positions of the first sync patterns matching with positions of the prepits, is larger than a predetermined number, and otherwise selecting codes that represent second sync patterns for the remainder of the sync frames such that each of the second sync pattern is formed so as to meet a low-frequency reduction scheme;
• generating modulation codes based on the sync frames in which the selected codes are inserted, by modulating the sync frames containing the selected codes in accordance with a predetermined modulation scheme;
• generating a sequence of recording pulses by converting the modulation codes through a predetermined conversion scheme;
• and
• detecting a prepit position signal from one of the prepits for each of the sync frames during the writing of the recording pulses to the recording medium, so that a write position control is performed based the detected prepit position signal.

An information recording apparatus for recording a sequence of sync frames, indicative of data, onto tracks of an optical recording medium in which prepits are formed on lands between the tracks at given intervals, and in which sync patterns, providing synchronization on a sync-frame basis, are inserted in the sync frames such that each sync pattern has a length in a track direction larger than a length of one of the prepits and a position of each sync pattern matches with a position of at least one of the prepits, the information recording apparatus comprising:

• sync information generating means for selecting codes that represent sync patterns for the sync frames such that each sync pattern is formed as a space on the recording medium;
• prepit position signal detecting means for detecting a prepit position signal from one of the prepits for each of the sync frames during the writing of the recording pulses to the recording medium;
• write position signal generating means for generating a write-position start signal based on the prepit position signal detected by the prepit position signal detecting means;
• and
• data encoding means for generating modulation codes based on the sync frames in which the codes selected by the sync information generating means are inserted, by modulating the sync frames containing the selected codes in accordance with a predetermined modulation scheme, the data encoding means generating a sequence of recording pulses by converting the modulation codes through a predetermined conversion scheme, and the data encoding means starting outputting the sequence of recording pulses in accordance with the write-position start signal supplied by the write position signal generating means.

An information recording apparatus for recording a sequence of sync frames, indicative of data, onto tracks of an optical recording medium in which prepits are formed on lands between the tracks at given intervals, and in which sync patterns, providing synchronization on a sync-frame basis, are inserted in the sync frames such that each sync pattern has a length in a track direction larger than a length of one of the prepits and a position of each sync pattern matches with a position of at least one of the prepits, the information recording apparatus comprising:

• sync information generating means for selecting codes that represent first sync patterns for a portion of the sync frames such that each first sync pattern is formed as a space on the recording medium, and selecting codes that represent second sync patterns for the remainder of the sync frames such that each second sync pattern is formed on the recording medium so as to meet a low-frequency reduction scheme;
• prepit position signal detecting means for detecting a prepit position signal from one of the prepits for each of the sync frames during the writing of the recording pulses to the recording medium;
• write position signal generating means for generating a write-position start signal based on the prepit position signal detected by the prepit position signal detecting means;
• and
• data encoding means for generating modulation codes based on the sync frames in which the codes selected by the sync information generating means are inserted, by modulating the sync frames containing the selected codes in accordance with a predetermined modulation scheme, the data encoding means generating a sequence of recording pulses by converting the modulation codes through a predetermined conversion scheme, and the data encoding means starting outputting the sequence of recording pulses in accordance with the write-position start signal supplied by the write position signal generating means.

An information recording apparatus for recording a sequence of sync frames, indicative of data, onto tracks of an optical recording medium in which prepits are formed on lands between the tracks at intervals that are equal to an integral multiple of a unit length corresponding to a channel bit, and in which sync patterns, providing synchronization on a sync-frame basis, are inserted in the sync frames such that each sync pattern has a length in a track direction larger than a length of one of the prepits and a position of each sync pattern matches with a position of at least one of the prepits, the information recording apparatus comprising:

• sync information generating means for selecting codes that represent first sync patterns for a portion of the sync frames such that each of the first sync patterns is formed as a space on the recording medium, when positions of the first sync patterns match with positions of the prepits, and for selecting codes that represent second sync patterns for the remainder of the sync frames such that each of the second sync pattern is formed on the recording medium so as to meet a low-frequency reduction scheme, when positions of the second sync patterns do not match with the positions of the prepits;
• prepit position signal detecting means for detecting a prepit position signal from one of the prepits for each of the sync frames during the writing of the recording pulses to the recording medium;
• write position signal generating means for generating a write-position start signal based on the prepit position signal detected by the prepit position signal detecting means;
• and
• data encoding means for generating modulation codes based on the sync frames in which the codes selected by the sync information generating means are inserted, by modulating the sync frames containing the selected codes in accordance with a predetermined modulation scheme, the data encoding means generating a sequence of recording pulses by converting the modulation codes through a predetermined conversion scheme, and the data encoding means starting outputting the sequence of recording pulses in accordance with the write-position start signal supplied by the write position signal generating means.

An information recording apparatus for recording a sequence of sync frames, indicative of data, onto tracks of an optical recording medium in which prepits are formed on lands between the tracks at given intervals, and in which sync patterns, providing synchronization on a sync-frame basis, are inserted in the sync frames such that each sync pattern has a length in a track direction larger than a length of one of the prepits and a position of each sync pattern matches with a position of at least one of the prepits, the information recording apparatus comprising:

• sync information generating means for selecting codes that represent first sync patterns for a portion of the sync frames such that each of the first sync patterns is formed as a space, when the number of the first sync patterns being successively formed as a mark, positions of the first sync patterns matching with positions of the prepits, is larger than a predetermined number, and otherwise for selecting codes that represent second sync patterns for the remainder of the sync frames such that each of the second sync pattern is formed so as to meet a low-frequency reduction scheme;
• prepit position signal detecting means for detecting a prepit position signal from one of the prepits for each of the sync frames during the writing of the recording pulses to the recording medium;
• write position signal generating means for generating a write-position start signal based on the prepit position signal detected by the prepit position signal detecting means;
• and
• data encoding means for generating modulation codes based on the sync frames in which the codes selected by the sync information generating means are inserted, by modulating the sync frames containing the selected codes in accordance with a predetermined modulation scheme, the data encoding means generating a sequence of recording pulses by converting the modulation codes through a predetermined conversion scheme, and the data encoding means starting outputting the sequence of recording pulses in accordance with the write-position start signal supplied by the write position signal generating means.