Abstract: Optical discs are adapted to be used with a light beam having a wavelength of 405 nm for recording or reproducing data. Error correcting blocks for recording BMID including copy protection key information are defined on optical discs (1) dedicated to data reproduction. A data string of BMID to be recorded has 64 bytes. An error correcting block is constituted by 304 columns of error correcting code words (LDC). A BMID data string of 64 bytes is inserted to predetermined 64 error correcting code words (LDC) of a block (304 columns of error correcting code words). The total code length of the predetermined 64 error correcting code words (LDC) is 248 bytes, of which a predetermined byte (symbol) is replaced by a predetermined byte (symbol) of the BMID data string.

Abstract: In step S1, the address generator generates address information composed of a sync signal which is recorded on an optical disc, address data and an error correction code for the address data, pre-encodes and supplies it to a modulator. At the same time, a carrier signal generator generates a carrier signal which is to carry the address information, and supplies it to the modulator. In step S2, the modulator makes MSK modulation of the carrier signal supplied from the carrier signal generator on the basis of the pre-encoded address information supplied from the address generator, and supplies a resultant MSK modulation signal to a wobbling unit. In step S3, the wobbling unit forms, on the optical disc, a spiral groove wobbled adaptively to the MSK modulation signal supplied from the modulator. In this optical disc, a given address can be accessed quickly and accurately.

Abstract: Four ECC blocks are recorded in a burst cutting area of an optical disc. Each ECC block is constituted by a BCA content code of 1 byte, content data length of 1 byte, and content data of 14 bytes. Of the BCA content data, the leading 6 bits are used for application ID and the remaining 2 bits are used for block number. Disc ID is stored in the content data. Since the four ECC blocks exist, the optical disc can be managed individually by four applications at the maximum. Thus it becomes possible to manage the same optical disc by a plurality of applications.

Abstract: In step S1, the address generator generates address information composed of a sync signal which is recorded on an optical disc, address data and an error correction code for the address data, pre-encodes and supplies it to a modulator. At the same time, a carrier signal generator generates a carrier signal which is to carry the address information, and supplies it to the modulator. In step S2, the modulator makes MSK modulation of the carrier signal supplied from the carrier signal generator on the basis of the pre-encoded address information supplied from the address generator, and supplies a resultant MSK modulation signal to a wobbling unit. In step S3, the wobbling unit forms, on the optical disc, a spiral groove wobbled adaptively to the MSK modulation signal supplied from the modulator. In this optical disc, a given address can be accessed quickly and accurately.

Abstract: An ECC block is constituted by RS(248,216,33). Of a data length of 216 bytes (symbols), only 16 bytes are allocated to BCA data and the remaining 200 bytes are used for fixed data having a predetermined value. Using the fixed data of 200 bytes and the BCA data of 16 bytes, parities of 32 bytes (symbols) are calculated. Only the BCA data of 16 bytes and the parities of the former 16 bytes of the 32-byte parities, that is, a total of 32 bytes only, are recorded in a burst cutting area of an optical disc. In decoding, error correction processing is carried out by using the fixed data of 200 bytes. The unrecorded parities of 16 bytes are processed as having been erased. Thus, the error correction capability in a burst cutting area of an optical disc can be improved.

Abstract: An ECC block is constituted by RS(248, 216, 33). Of a data length of 216 bytes (symbols), only 16 bytes are allocated to BCA data and the remaining 200 bytes are used for fixed data having a predetermined value. Using the fixed data of 200 bytes and the BCA data of 16 bytes, parities of 32 bytes (symbols) are calculated. Only the BCA data of 16 bytes and the parities of the former 16 bytes of the 32-byte parities, that is, a total of 32 bytes only, are recorded in a burst cutting area of an optical disc. In decoding, error correction processing is carried out by using the fixed data of 200 bytes. The unrecorded parities of 16 bytes are processed as having been erased. Thus, the error correction capability in a burst cutting area of an optical disc can be improved.

Abstract: In step S1, the address generator generates address information composed of a sync signal which is recorded on an optical disc, address data and an error correction code for the address data, pre-encodes and supplies it to a modulator. At the same time, a carrier signal generator generates a carrier signal which is to carry the address information, and supplies it to the modulator. In step S2, the modulator makes MSK modulation of the carrier signal supplied from the carrier signal generator on the basis of the pre-encoded address information supplied from the address generator, and supplies a resultant MSK modulation signal to a wobbling unit. In step S3, the wobbling unit forms, on the optical disc, a spiral groove wobbled adaptively to the MSK modulation signal supplied from the modulator. In this optical disc, a given address can be accessed quickly and accurately.

Abstract: Four ECC blocks are recorded in a burst cutting area of an optical disc. Each ECC block is constituted by a BCA content code of 1 byte, content data length of 1 byte, and content data of 14 bytes. Of the BCA content data, the leading 6 bits are used for application ID and the remaining 2 bits are used for block number. Disc ID is stored in the content data. Since the four ECC blocks exist, the optical disc can be managed individually by four applications at the maximum. Thus it becomes possible to manage the same optical disc by a plurality of applications.

Abstract: Four ECC blocks are recorded in a burst cutting area of an optical disc. Each ECC block is constituted by a BCA content code of 1 byte, content data length of 1 byte, and content data of 14 bytes. Of the BCA content data, the leading 6 bits are used for application ID and the remaining 2 bits are used for block number. Disc ID is stored in the content data. Since the four ECC blocks exist, the optical disc can be managed individually by four applications at the maximum. Thus it becomes possible to manage the same optical disc by a plurality of applications.

Abstract: With the disc-shaped recording medium, or the disc manufacturing method according to the present invention, for both the single-layer disc and the multi-layer disc, a recording layer L0, which is to be the first layer, is at the same distance, along the direction of disc thickness, from the surface of the cover layer CVLs on which falls the laser light. For the multi-layer disc, the second layer L1 and the following layer(s) are formed at the locations which are closer to the cover layer CVLs than the first layer L0. Management information may be recorded by mobbling grooves, each layermay have tert areas, defect information, a replacement area. Thus, it is possible to improve compatibility, reliability and accessibility between a single-layer disc and a multi-layer disc. The spherical aberration for the recording/reproducing light may be controlled with respect to the selected layer.

Abstract: A record carrier has a servo track (4) indicating an information track (9) intended for recording information blocks. The servo track (4) has a periodic variation of a physical parameter at a predetermined frequency and modulated parts for encoding position information at regular intervals. The modulated parts start with a bit sync element and are of a data type having a data bit element or of a word sync type having a word sync element. The bit sync element, word sync element and the data bit element being modulated according to a same predetermined type of modulation of the periodic variation. All distances between two adjacent of the elements constituting the modulated parts are unique.

Abstract: In step S1, the address generator generates address information composed of a sync signal which is recorded on an optical disc, address data and an error correction code for the address data, pre-encodes and supplies it to a modulator. At the same time, a carrier signal generator generates a carrier signal which is to carry the address information, and supplies it to the modulator. In step S2, the modulator makes MSK modulation of the carrier signal supplied from the carrier signal generator on the basis of the pre-encoded address information supplied from the address generator, and supplies a resultant MSK modulation signal to a wobbling unit. In step S3, the wobbling unit forms, on the optical disc, a spiral groove wobbled adaptively to the MSK modulation signal supplied from the modulator. In this optical disc, a given address can be accessed quickly and accurately.

Abstract: The information such as address is to be efficiently formed into wobble components and further the S/N ratio in reproducing the information formed into the wobble components is to be improved. In an optical disc of the present invention, there are recorded in a wobble the address information modulated in accordance with the MSK (minimum shift keying) system and the address information modulated in accordance with a modulation system in which even harmonics signals are added to a sinusoidal carrier signal and in which the polarity of the harmonics signal is changed depending on the sign of the data for modulation.

Abstract: With the disc-shaped recording medium, or the disc manufacturing method according to the present invention, for both the single-layer disc and the multi-layer disc, a recording layer L0, which is to be the first layer, is at the same distance, along the direction of disc thickness, from the surface of the cover layer CVLs on which falls the laser light. For the multi-layer disc, the second layer L1 and the following layer(s) are formed at the locations which are closer to the cover layer CVLs than the first layer L0. Management information may be recorded by mobbling grooves, each layermay have tert areas, defect information, a replacement area. Thus, it is possible to improve compatibility, reliability and accessibility between a single-layer disc and a multi-layer disc. The spherical aberration for the recording/reproducing light may be controlled with respect to the selected layer.

Abstract: An optical disk (10) of the present invention comprises a substrate (11) included a biodegradable resin or polyolefin resin, a recording layer (13) provided on at least one side of the substrate (11), and a printing layer (15) provided on the other side of substrate (11), wherein recording layer (13) and printing layer (15) have a base material layer (recording layer base material, printing base material (21)) included a non-hydrophilic film. This type of optical disk (10) has performance equal to that of conventional optical disks, has a minimal effect on the environment during disposal and is able to suppress warping of the substrate.

Abstract: An optical disc or other optical recording medium enables reading barcode-shaped-BCA marks in a burst cutting area (BCA) with tracking on while making tampering with the BCA marks difficult. The optical disc 100 has a first area 102 containing tracks at a first track pitch d2, and a second area 101 containing tracks at a second track pitch d1. The barcode-shaped marks 104 are recorded in the second area, and the second track pitch is wider than the first track pitch.

Abstract: Four ECC blocks are recorded in a burst cutting area of an optical disc. Each ECC block is constituted by a BCA content code of 1 byte, content data length of 1 byte, and content data of 14 bytes. Of the BCA content data, the leading 6 bits are used for application ID and the remaining 2 bits are used for block number. Disc ID is stored in the content data. Since the four ECC blocks exist, the optical disc can be managed individually by four applications at the maximum. Thus it becomes possible to manage the same optical disc by a plurality of applications.

Abstract: The information such as address is to be efficiently formed into wobble components and further the S/N ratio in reproducing the information formed into the wobble components is to be improved. In an optical disc of the present invention, there are recorded in a wobble the address information modulated in accordance with the MSK (minimum shift keying) system and the address information modulated in accordance with a modulation system in which even harmonics signals are added to a sinusoidal carrier signal and in which the polarity of the harmonics signal is changed depending on the sign of the data for modulation.

Abstract: An ECC block is constituted by RS(248,216,33). Of a data length of 216 bytes (symbols), only 16 bytes are allocated to BCA data and the remaining 200 bytes are used for fixed data having a predetermined value. Using the fixed data of 200 bytes and the BCA data of 16 bytes, parities of 32 bytes (symbols) are caculated. Only the BCA data of 16 bytes and the parities of the former 16 bytes of the 32-byte parities, that is, a total of 32 bytes only, are recorded in a burst cutting area of an optical disc. In decoding, error correction processing is carried out by using the fixed data of 200 bytes. The unrecorded parities of 16 bytes are processed as having been erased. Thus the error correction capability in a burst cutting area of an optical disc can be improved.

Abstract: A header in which an address signal has been recorded is provided on the disc for every predetermined sector interval. Recording data is arranged in an error correction encoding block and the error correcting process is performed. The error correction encoding block is divided into a plurality of portions in a predetermined direction, thereby forming sectors S1, S2, S3, . . . . The data of each sector is recorded subsequent to the header. Upon reproduction, the header is detected and the data is reproduced for every sector. One of the error correcting processes is performed in the reproduced data in the sectors S1, S2, S3, . . . . In the case where errors cannot be corrected by the error correcting process in the reproduced data in the sector, the error correction block including the sectors S1, S2, S3, . . . is reproduced and the error correcting processes are performed in the sequences in two directions.