Abstract: A vacuum transfer apparatus including an auxiliary vacuum chamber and a main vacuum chamber is used for transferring an uneven pattern to a disk substrate with a stamper. The auxiliary vacuum chamber is vacuumized or opened to air because the disk substrate is conveyed to and from the vacuum transfer apparatus through the auxiliary vacuum chamber. The disk substrate conveyed to the auxiliary vacuum chamber and then to the main vacuum chamber after the auxiliary vacuum chamber is vacuumized. In the main vacuum chamber, transferring of the uneven pattern with the stamper, curing of UV-curable resin, and removal of the stamper are performed to provide a disk substrate with the uneven pattern. Then, the disk substrate is conveyed from the vacuum transfer apparatus through the auxiliary vacuum chamber. An operation at the auxiliary-vacuum-chamber side and an operation at the main-vacuum-chamber side are performed in parallel.

Abstract: The BCA recording and reproducing apparatus performs recording of data onto an optical disc placed on a recording turntable, reproduction of data recorded on an optical disc placed on a reproducing turntable and ejection of an optical disc placed on an exchanging table and placement of a new optical disc on the exchanging table in parallel. A processing time is thereby shortened compared with the case of performing data recording, reproduction and exchange in series.

Abstract: A method of recording data includes: a first recording step of recording data in a condition that, within a certain error correction block in a data format in which error correction blocks with n rows and m columns including at least main data, error detection code, and error correction parity are formed, an allocated location of additional supplementary information is set in a location in the same column as an allocated location of the error detection code, and an additional recording area is formed for recording additional information containing the additional supplementary information and the error detection code and the error correction parity necessary to be recorded according to the recording of the additional supplementary information; and a second recording step of recording the additional information in the additional recording area after the data recording at the first step is executed.

Abstract: In an optical device, a number of structures having higher portions or lower portions are arranged at a fine pitch equal to or shorter than a wavelength of visible light on a surface of a base. Each of the structures is arranged to form a plurality of arc track rows on the surface of the base, and to form a quasi-hexagonal lattice pattern, and the structure has an elliptical cone or truncated elliptical cone shape having a major axis in a circumferential direction of the arc tracks.

Abstract: A recording medium including at least a lead-in region, a recording region in which information is recorded, and a lead-out region. In this configuration, medium identification information that includes user identification information accessible by the user is recorded in at least any one of the lead-in region, the recording region, and the lead-out region.

Abstract: A read-only optical disc medium is disclosed. The disc medium includes: an information recording area in which information is recorded by means of an embossed pit array formed in a convexo-concave shape having a reflective layer deposited thereon; a test writing area which is used for test write recording of a mark formed by dissipating or decreasing the reflective layer; and an additional write area in which a record data string is formed of a mark by dissipating or decreasing the reflective layer under a recording condition decided in accordance with a result of test write recording performed in the test writing area.

Abstract: A solvent-free photocurable resin composition is provided which can be applied to the surface of optical discs or the like to form a highly transparent protective film that can stably adhere to the surface and effectively protect the surface from scratches. The solvent-free photocurable resin composition contains a urethane(meth)acrylate oligomer, a trifunctional (meth)acrylic acid ester monomer, a photopolymerization initiator, and a dilution monomer. The dilution monomer contains a fluorine-based (meth)acrylic acid ester monomer having three or more fluorine atoms and a monofunctional or difunctional (meth)acrylic acid ester monomer in amounts of from 10 to 40 wt % and from 10 to 30 wt %, respectively.

Abstract: A processing method is disclosed. When a recording medium on which at least one program has been recorded is loaded, a program for a user registration is started. Identification information unique to the recording medium is read therefrom. The identification information that has been read and user's information that has been obtained are correlatively stored. After they have been stored, the program data is read from the recording medium.

Abstract: An optical disk-producing sheet 1 comprising an energy ray-curable stamper-receiving layer 11 onto which can be transferred convexoconcave of a stamper S, and release sheets 12 and 12?, wherein the adhesive strength after curing of the stamper-receiving layer 11 to a reflective layer 3 is greater than the adhesive strength after curing of the stamper-receiving layer 11 to the stamper S, the difference between the two adhesive strengths being not less than 50 mN/25 mm. According to this optical disk-producing sheet 1, when the cured stamper-receiving layer 11 and the stamper S are separated from one an other, there is no peeling away between the stamper-receiving layer 11 and the reflective layer 3.

Abstract: A large capacity recording medium is formed by bonding at least two disc-shaped recording plates to provide a structure adapted to absorb any manufacturing errors in the direction of the height of the recording medium.

Abstract: A space 12 is formed at a tip portion of a nozzle 1 so as to decrease a thermal transfer of the nozzle 1. Alternatively, a center portion of one of a semi-spherically protruded surface of the tip portion of the nozzle 1 and a semi-spherically recessed surface of a sprue bush protrudes so that the radius of curvature of one semi-spherical surface is the same as the radius of curvature of the other semi-spherical surface. As a result, since the nozzle 1 and the sprue bush 2 are surface-contacted, heat of the tip portion of the nozzle 1 absorbed to the sprue bush 2 is increased. Thus, the temperature of the tip portion of the nozzle 1 can be lowered easily. After the resin material injected into the molding cavity 11 is cooled, when the sprue portion is removed from the fixed die, a tip portion of a rod-shaped protrusion portion of the sprue can be properly cut.

Abstract: A recording method for converting m-bit data into n-bit (where n>m) bit data whose run length is restricted and recoding the converted data on a recording medium, the recording method comprising the steps of when at least preceded data is data containing a special data pattern, lightening the restriction of the run length; and recording data so that the cumulative value of DC components per unit time increase when the data is reproduced in the state that the run length is restricted.

Abstract: A recording method for converting m-bit data into n-bit (where n>m) data whose run length is restricted and recording the converted data on a recording medium, the recording method comprising the step of selecting first n-bit data according to an immediately preceded n-bit data, first n-bit data immediately followed thereby, and second n-bit data immediately followed thereby so that the cumulative value of DC components per unit time becomes small.

Abstract: A beam emitted from a light source 58 is converted into a line-shaped collimated beam by a lens 59. The line-shaped collimated beam reaches a beam splitter 60. The beam splitter 60 reflects a half of the incident beam. The reflected beam vertically reaches a line-shaped area of a front surface of an optical disc 65. The beam splitter 60 transmits the remaining beam. The transmitted beam obliquely reaches the line-shaped area of the front surface of the optical disc 65. The light amount of the reflected beam that vertically reaches the front surface of the optical disc 65 is detected by a first camera 62. Since both the incident beam and the reflected beam are perpendicular to the front surface of the optical disc 65, even if a large defect exists on the front surface, no virtual image occurs in an image photographed by a first camera 62. As a result, the size of the defect can be accurately detected.

Abstract: A recording method includes the steps of generating recording data in such a manner that, when m-bit data is converted into a data symbol of n bits (m<n), and connection bits such that the summed value of DC components per unit time decreases are selected from among a plurality of connection bits and are added after the m-bit data symbol, the connection bits differing from connection bits which are added when the n-bit data symbol is a data symbol other than the special data symbol are added to generate recording data; and recording the generated recording data on a recording medium.

Abstract: With data of four symbols (FIG. 11A), a parity of two symbols (FIG. 11B) is created. These six symbols are EFM-modulated. Each symbol of eight bits is converted into a pattern of 14 bits (FIG. 11C). In a pit/land sequence formed on a disc (FIG. 11D), two symbols are rewritten. One symbol is (0×40). When an additional recording process is performed for the bit/land sequence, the pit length becomes long (FIG. 11E). The reproduced 14-bit data is converted into eight bits on the reproducing side. Thus, the original data (0×40) is rewritten to (0×22). A parity is also changed so that the additionally recorded data symbol (0×22) is not detected as an error.

Abstract: A recording method, wherein, when a certain portion of main data is recorded by being encoded by a first encoding method and the other portions of the main data is recorded by being encoded by a second encoding method, an encoding process is performed by the first encoding method so that, when data which is recorded in such a manner that the data encoded by the first encoding method is decoded by a decoding method corresponding to the first encoding method, and thereafter, is further encoded by the second encoding method, is decoded by a decoding method corresponding to the second encoding method, the sum value of DC components per unit time increases.

Abstract: A method is provided for recording medium having a substrate on which first data and second data are recorded as a protrusion/depression pattern and a reflective layer that is provided on a surface having the protrusion/depression pattern. Laser light is radiated to the reflective layer to change the protrusion/depression pattern of the second data, and third data used for identifying the recording medium is additionally recorded at a predetermined position on the recording medium.

Abstract: A recording medium has a first area in which data encoded with a first error correction code is recorded and a second area in which data encoded with the first error correction code and data decodable with a second error correction code that is different from the first error correction code are mixedly recorded. Data that causes the cumulated value of a DC component per unit period of data reproduced from the second area to deviate is recorded in the second area.

Abstract: A resin ring 51 is press-fitted into a grove portion formed in an inner periphery surface of an interlocking ring 4. The resin ring 51 is made of a hard resin such as Teflon. The resin ring 51 as a low frictional lubricative member is interposed between the interlock ring 4 and an outer periphery ring 3. In addition, a cavity 6 as a closed space is formed between a stamper 1b as a molding surface of a fixed side mirror 1 and a mirror side molding surface 2b of a moving side mirror 2. While the moving side mirror 2 is being press-contracted to the fixed side mirror 1, when a resin material is filled into the cavity 6, the outer periphery ring 3 is slidably held in a groove of the moving side mirror 2 with predetermined clearances. In the interlock ring 4, a plurality of openings 4a which relieve gas produced by the disc resin material filled into the cavity 6 are formed.