Abstract: A main information area 31 capable of recording an information signal and a subsidiary information area 32 for recording subsidiary information that is different from the information signal are divided in one principal plane direction of a substrate, and an information layer for recording the information signal in the main information area 31 is provided also in the subsidiary information area 32, and medium identification information for distinguishing the medium optically is recorded in the information layer of the subsidiary information area 32 without changing the shape of the information layer. As a result, the medium identification information can be recorded in an optical recording medium 1 stably. In particular, the initialization of a phase change type optical recording medium and the recording of the medium identification information can be performed at the same time, so that the production process can be simplified, and the production costs can be reduced.

Abstract: In an optical information recording medium having at least two information layer, guide grooves for tracking or sample pits or information pits corresponding to information signals are formed on a surface of a first substrate. A first information layer formed by a thin film for reflecting a portion of a light beam made incident on the first substrate and permitting penetration of a portion of the light beam is formed on a surface of the first substrate. Guide grooves for tracking or information pits corresponding to information signals are formed on a surface of a second substrate. A second information layer having a reflectance higher than that of the first information layer is formed on a surface of the second substrate. Between the first information layer and the second information layer, there is formed a transparent separation layer for positioning the first information layer and the second information layer to be spaced a predetermined distance apart from each other.

Abstract: The present invention relates to an optical information recording medium including a disk-shaped transparent substrate and a recording layer for recording, reproducing or erasing information by irradiation of laser light, the recording layer being formed over the substrate. The recording layer of the present invention includes information tracks including groove tracks and land tracks that are formed alternately in a radial direction of the disk. The information tracks comprise information recording regions and address regions interposed between the information recording regions, the information recording regions and the address regions being arranged along the tracking direction of the laser light.

Abstract: In a single-sided multi-layer optical disk, “n” information layers are formed so that sector address portions (9, 11) do not overlap with each other in a stack direction in a combination of adjacent information layers (1, 4) and an optical separating layer (3) is disposed between the information layers. Thereby, signals of the sector address portion can be reproduced stably without being affected by the sector address portions of the adjacent information layer(s).

Abstract: An optical information recording device includes a linear velocity setting circuit for setting a first linear velocity v1 and a second linear velocity v2 higher than the first linear velocity v1 for a optical information recording medium, a recording pulse generation circuit for generating a recording pulse signal, depending on the setting by the linear velocity setting circuit, and a laser drive circuit for irradiating the medium with the laser light based on the recording pulse signal generated by the recording pulse generation circuit.

Abstract: A plurality of types of recording pulse control rules for which the recording pulse waveform is determined according to the information signals to be recorded are stored in advance in an optical disk. When recording to the optical disk, information is recorded using a recording pulse where, due to the focused laser beam, the temperature in the recording layer cools more rapidly at a second information recording layer closer to the side where light is incident than at a first information recording layer farther away from the side where light is incident.

Abstract: A recording and reproduction apparatus for a recording medium including a plurality of information layers includes a focusing signal generation section for generating focusing signals F+and F?in accordance with a light beam reflected by the recording medium; a focusing control section for generating a focusing error signal in accordance with a difference between the focusing signals F+and F?, and performing focusing control for maintaining a distance between a focal point of the light beam and a target information layer within a prescribed tolerable range; and a gain setting section for setting a focusing servo gain in accordance with the focusing error signal. The focusing signal generation section generates the focusing signals F+ F? so that values of components thereof based on the light beam reflected by an information layer other than the target information layer are substantially equal while focusing control is being performed.

Abstract: A method by which, in an optical disk recording and reproducing device, the time required for a test recording performed prior to an actual information recording can be reduced according to characteristics of an optical disk. A random pattern signal is transmitted from a random pattern signal generating circuit 3 and recorded on a test track on an optical disk 1, and a bit error rate of a reproduction signal is measured. Only when a value of the bit error rate is not less than a fixed value, test pattern signals are transmitted from a test pattern signal generating circuit 4 and recorded. An edge timing of a reproduction signal is measured by an edge timing detecting circuit 13. Based on a result of the measurement, edge positions of a front-end pulse and a back-end pulse are corrected.

Abstract: An optical information recording and reproducing apparatus for recording and reproducing an information signal on/from both concave portions and convex portions of guide grooves formed on a recording medium is disclosed.

Abstract: A multivalued information recording method in which energy applied to information units on a recording medium is varied to record multivalued information. In accordance with a relationship between the multivalued information in a predetermined information unit and the multivalued information in information units adjacent to the predetermined information unit, the energy applied to the predetermined information unit is decided.

Abstract: An optical information recording medium of the present invention includes at least m (m is an integer of 2 or more) information layers, and each of the information layers includes a recording layer that changes irreversibly between a state A and a state B that are optically different from each other. In the case where the m information layers are taken as the first through m-th information layers in the order from a laser beam incidence side, when a recording layer included in the j-th information layer (j is an integer satisfying 1?j?m?1) is taken as the j-th recording layer, and when a transmittance of the j-th information layer at the time when the j-th recording layer is in the state A is TAj (%) and a transmittance of the j-th information layer at the time when the j-th recording layer is in the state B is TBj (%), the following relationship is satisfied in the j-th information layer: 0?|TAj?TBj|/(TAj,TBj)max?0.10 where (TAj,TBj)max is a larger value of TAj and TBj.

Abstract: A recording and reproduction apparatus for a recording medium including a plurality of information layers includes a focusing signal generation section for generating focusing signals F+ and F? in accordance with a light beam reflected by the recording medium; a focusing control section for generating a focusing error signal in accordance with a difference between the focusing signals F+ and F?, and performing focusing control for maintaining a distance between a focal point of the light beam and a target information layer within a prescribed tolerable range; and a gain setting section for setting a focusing servo gain in accordance with the focusing error signal. The focusing signal generation section generates the focusing signals F+ F? so that values of components thereof based on the light beam reflected by an information layer other than the target information layer are substantially equal while focusing control is being performed.

Abstract: A method and an apparatus are provided, which enable a user's standby time to be shortened or utilized effectively in the course of recording/reproduction of information with respect to an optical disk. Information recorded on a disk is reproduced preferentially, and after counting for a predetermined period of time, recording learning is conducted. Alternatively, management information is reproduced preferentially over recording learning, and recording learning is conducted while a user is confirming this information. Alternatively, the possibility of recording on a disk is identified, and reproduction preference or recording learning preference processing is conducted based the possibility. Alternatively, a rotation speed of a disk is controlled to be variable or constant, based on the possibility of recording.

Abstract: An optical information recording medium includes: a substantially disk-shaped substrate; and a recording layer formed on a surface of the substrate for recording, reproducing and erasing information by irradiation with a laser beam. A test recording region for test recording and an information recording region for recording the information at least are arranged on the surface of the substrate. In the test recording region and the information recording region arranged on the surface of the substrate, a test recording track and an information recording track respectively are formed in a spiral-shaped arrangement or in a concentric arrangement. A track pitch of the test recording track is wider than a track pitch of the information recording track.

Abstract: The present invention provides an optical information recording apparatus and method capable of effectively determining appropriate recording parameters in a short time with favorable efficiency, when recording information onto an optical disk having different information recording conditions and information recording characteristics. An information recording condition or an information recording characteristic of an optical disk 1 is identified, and a recording pulse position is corrected at a correction accuracy according to the identifies information recording condition or information recording characteristic, such that a recording mark is formed in a predetermined position.

Abstract: A main information area 31 capable of recording an information signal and a subsidiary information area 32 for recording subsidiary information that is different from the information signal are divided in one principal plane direction of a substrate, and an information layer for recording the information signal in the main information area 31 is provided also in the subsidiary information area 32, and medium identification information for distinguishing the medium optically is recorded in the information layer of the subsidiary information area 32 without changing the shape of the information layer. As a result, the medium identification information can be recorded in an optical recording medium 1 stably. In particular, the initialization of a phase change type optical recording medium and the recording of the medium identification information can be performed at the same time, so that the production process can be simplified, and the production costs can be reduced.

Abstract: A main information area 31 capable of recording an information signal and a subsidiary information area 32 for recording subsidiary information that is different from the information signal are divided in one principal plane direction of a substrate, and an information layer for recording the information signal in the main information area 31 is provided also in the subsidiary information area 32, and medium identification information for distinguishing the medium optically is recorded in the information layer of the subsidiary information area 32 without changing the shape of the information layer. As a result, the medium identification information can be recorded in an optical recording medium 1 stably. In particular, the initialization of a phase change type optical recording medium and the recording of the medium identification information can be performed at the same time, so that the production process can be simplified, and the production costs can be reduced.

Abstract: An optical information recording and reproducing apparatus for recording and reproducing an information signal on/from both concave portions and convex portions of guide grooves formed on a recording medium is disclosed.

Abstract: A main information area 31 capable of recording an information signal and a subsidiary information area 32 for recording subsidiary information that is different from the information signal are divided in one principal plane direction of a substrate, and an information layer for recording the information signal in the main information area 31 is provided also in the subsidiary information area 32, and medium identification information for distinguishing the medium optically is recorded in the information layer of the subsidiary information area 32 without changing the shape of the information layer. As a result, the medium identification information can be recorded in an optical recording medium 1 stably. In particular, the initialization of a phase change type optical recording medium and the recording of the medium identification information can be performed at the same time, so that the production process can be simplified, and the production costs can be reduced.

Abstract: A main information area 31 capable of recording an information signal and a subsidiary information area 32 for recording subsidiary information that is different from the information signal are divided in one principal plane direction of a substrate, and an information layer for recording the information signal in the main information area 31 is provided also in the subsidiary information area 32, and medium identification information for distinguishing the medium optically is recorded in the information layer of the subsidiary information area 32 without changing the shape of the information layer. As a result, the medium identification information can be recorded in an optical recording medium 1 stably. In particular, the initialization of a phase change type optical recording medium and the recording of the medium identification information can be performed at the same time, so that the production process can be simplified, and the production costs can be reduced.