Optical information recording medium with sector address information

An optical information recording medium comprising a substrate and at least two information layers formed on the substrate, the information layer being formed of a thin film showing a change that can be detected optically by light beam irradiation,

• wherein a separating layer that is transparent to a wavelength of the light beam is formed between the information layers, and
• each information layer comprises:
• a sector area having sector address portions and data areas for recording information signals, the sector address portion and the data area being divided in a circumferential direction,
• a management area on which a type of information layer or recording conditions is written, and
• a sector position identifier for identifying a sector position and determining an amount of sector dislocation between the information layers, having a certain relationship to the sector area of the information layer in the circumferential direction.

A recording method for an optical information recording medium comprising:

• recording information signals on the optical information recording medium,
• the optical information recording medium comprising a substrate, at least two information layer formed on the substrate, and a separating layer formed between the information layers;
• the information layer being formed of a thin film showing a change that can be detected optically by light beam irradiation, the separating layer being transparent to a wavelength of the light beam, and each information layer comprising a sector area having sector address portions and data areas for recording information signals, the sector address portion and the data area being divided in a circumferential direction,
• wherein each information layer further comprises a sector position identifier having a certain relationship to the sector area in the circumferential direction, and
• dislocation between the sector position identifiers of the respective information layers is detected, so that identification information about an amount of dislocation between the sector address portions of the respective information layers in the circumferential direction is obtained and the identification information is recorded on at least one of the information layers.

A recording method for an optical information recording medium comprising:

• recording information signals on the optical information recording medium,
• the optical information recording medium comprising a substrate, at least two information layers formed on the substrate, and a separating layer formed between the information layers;
• the information layer being formed of a thin film showing a change that can be detected optically by light beam irradiation, the separating layer being transparent to a wavelength of the light beam, and each information layer comprising a sector area having sector address portions and data areas for recording information signals, the sector address portion and the data area being divided in a circumferential direction,
• wherein among the information layers, a signal is recorded on continuous tracks in the sector area of the information layer on a light incident side with at least one sector being left unrecorded,
• a signal is reproduced from the information layer that is further from the information layer on the light incident side, and
• a time difference between a pulse-fall point of the sector address portion of the distant information layer, corresponding to the unrecorded portion of the information layer on the light incident side, and a pulse-rise point of the recorded portion of the information layer on the light incident side is calculated, so that identification information about an amount of dislocation between the sector address portions of the respective information layers in the circumferential direction is obtained and the identification information is recorded on at least one of the information layers.

A recording method for an optical information recording medium comprising:

• recording information signals on the optical information recording medium,
• the optical information recording medium comprising a substrate, at least two information layers formed on the substrate, and a separating layer formed between the information layers;
• the information layer being formed of a thin film showing a change that can be detected optically by light beam irradiation, the separating layer being transparent to a wavelength of the light beam, and each information layer comprising a sector area having sector address portions and data areas for recording information signals, the sector address portions and the data area being divided in a circumferential direction,
• wherein a guide groove in the data area is formed of a wobbled groove wobbling in a predetermined cycle, and
• an amount of wobble is measured, so that identification information about an amount of dislocation between the sector address portions of the respective information layers in the circumferential direction is obtained and the identification information is recorded on at least one of the information layers.

A recording reproducing apparatus for an optical information recording medium, performing recording/reproduction of information signals on the optical information recording medium,

• the optical information recording medium comprising a substrate, at least two information layers formed on the substrate, and a separating layer formed between the information layers;
• the information layer being formed of a thin film showing a change that can be detected optically by light beam irradiation, the separating layer being transparent to a wavelength of the light beam, and each information layer comprising a sector area having sector address portions and data areas for recording information signals, the sector address portion and the data area being divided in a circumferential direction,
• the recording/reproducing apparatus comprising:
• a sector dislocation identifying means for detecting an amount of dislocation between the sector areas of the respective information layers in the circumferential direction;
• a gate generating means for controlling timing for correcting fluctuation in a reproduced signal, caused by an effect of a recorded state of each information layer, based on the detected dislocation amount, and
• a reproduced signal correcting means for correcting a reproduced signal in accordance with a gate signal from the gate generating means.

A recording/reproducing apparatus for an optical information recording medium, performing recording/reproduction of information signals on the optical information recording medium,

• the optical information recording medium comprising a substrate, at least two information layers formed on the substrate, and a separating layer formed between the information layers;
• the information layer being formed of a thin film showing a change that can be detected optically by light beam irradiation, the separating layer being transparent to a wavelength of the light beam, and each information layer comprising a sector area having sector address portions and data areas for recording information signals, the sector address portion and the data area being divided in a circumferential direction,
• the recording/reproducing apparatus comprising:
• a sector dislocation identifying means for detecting an amount of dislocation between the sector areas of the respective information layers in the circumferential direction;
• a gate generating means for controlling timing for correcting fluctuation in recording power, caused by an effect of a recorded state of each information layer, based on the detected dislocation amount, and
• a power switching means for switching recording power in accordance with a gate signal from the gate generating means.