Abstract: An optical disc of the present invention includes at least a light reflection layer and a light transmission layer formed on a substrate, wherein recording and reading are performed by a laser beam through the light transmission layer, the light transmission layer is formed from a cured film of a ultraviolet-curable composition containing an epoxy acrylate resin obtained by reacting a half ester compound (A), which is obtained from a lactone-adduct of a hydroxyalkyl (meth)acrylate (a1) and a dibasic acid anhydride (a2), and an epoxy resin (B), and the film thickness of the light transmission layer is from 50 to 150 ?m.

Abstract: Multi layer near-field optical recording using a moderate numerical aperture (NA) is superior to the high-NA (NA=2.0) first-surface single-layer technique. The use of very flat and thin spacer layers limits spherical aberration due to difference in layer depth. The thin spacer layers may have a high refractive index because their thickness allow for a relatively high absorption constant. This makes possible in principle an m-layer system, e.g. m=4, with NA=1.6 which may include a flat, protective cover layer. Further a medium for use in such a system is described.

Abstract: A write-once recording medium is provided, which comprises a management information area for recording management information for managing a recorded state, and a user data area for recording user data. The user data area is configured to contain at least one recording area. At least one session is configured to contain at least one of the at least one recording area. The management information contains range information indicating a recording range of the at least one recording area and identification information for identifying the recording area located at a boundary of the session.

Abstract: A defect entry, including position information of a defective block of a reference information layer and state information indicating the defective state of blocks of the other information layers located adjacent to a perpendicular direction at a position of the defective block of the reference information layer, is recorded on a holographic information storage medium. A method of inspecting for a defect includes determining whether blocks in a reference information layer are defective, and determining whether blocks of the other information layers located adjacent to a perpendicular direction at a position of a defective block of the reference information layer are defective, based on a result of the defect determination of the reference information layer.

Abstract: An information recording medium according to the present invention includes an information recording layer on which information is recordable, and is evaluated using an evaluation index which is found based on a ratio of a center of an amplitude of a reproduction signal corresponding to a second shortest mark and a second shortest space, with respect to a center of an amplitude of a reproduction signal corresponding to a longest mark and a longest space.

Abstract: An information storage medium includes an area in which updated disc-related information and recording-related information updated with a change in at least one of a disc version number and a recording speed is recorded along with existing disc-related information and recording-related information. The existing disc-related information and recording-related information are recorded, and the updated disc-related information and recording-related information is recorded in an area in which the existing disc-related information and recording-related information is recorded. Accordingly, data can be recorded/reproduced on/from a new version of information storage medium even using an existing drive.

Abstract: An optical recording medium of improved recording and reading characteristics, having both a read-only information recording layer and an information recording layer. The optical recording medium includes information recording layers capable of recording and reading by irradiation of laser light having a wavelength ? of 400 to 410 nm through an optical system having a numerical aperture NA of 0.8 to 0.9. In this medium, the information recording layers include at least a read-only information layer having information recorded in advance and an information recording layer different from the read-only information recording layer, the read-only information recording layer being capable of information recording of write-once type or rewritable type. The read-only information recording layer is stacked closest to a light incident surface of the laser light.

Abstract: A printable optical disc including an optical disc body, a waterproof protective film, and a first patterned layer is provided. The optical disc body has a printable surface. The waterproof protective film has an upper surface and a lower surface. The lower surface is disposed on the printable surface, and the upper surface has an optical grating pattern or a pixel pattern. The first patterned layer is disposed between the lower surface of the waterproof protective film and the printable surface.

Abstract: A recording medium, such as a high-density and/or optical recording medium including segment information recorded thereon, and apparatus and methods for recording to and reproducing from the recording medium, in order to improve data protection, data management and/or reproduction compatibility. The recording medium may contain at least one segment area which is an area on the disc controlled by a plurality of valid PACs and if the designated segment areas overlap with one another, control information of the respective PACs which control the overlapped area may be applied to control the overlapped area.

Abstract: An information recording medium (100) includes (i) a first recording layer (L0 layer) having a first track and (ii) a second recording layer (L1 layer) having a spiral or coaxial second track sharing the rotation center with the first track. (iii) The first recording layer has a first point (point Bx) indicated by a first address. (iv) The second recording layer has a second point (point Dx) which can be defined according to a predetermined positional relationship (allowable area: 10) with respect to the first point (point Bx).

Abstract: A recording medium in which data supplied from an information processing device is recorded includes: position detecting means for detecting a position of the recording medium; user authentication means for authenticating a user intending to use the data; recording means for recording data use limitation information; and data use limitation control means for controlling the limitation on the user's use of data on the basis of the data use limitation information.

Abstract: A method of recording data in a multilayered recordable optical recording medium is disclosed. When test recording is executed in a multilayered recordable optical recording medium having N recording layers (N is an integer of 2 or more), a test recording range in a test recording area of an (m+1)th recording layer is shifted relative to a test recording range in a test recording area of an mth recording layer by an amount greater than a difference of decentration amounts between the mth and the (m+1)th recording layers or a maximum decentration amount in the N recording layers. The shifting direction is inverse to a test recording range adding direction in a radius direction of the recording medium.

Abstract: A cleaning disc for a media reading device having a laser lens. The cleaning disc includes a first surface configured to face the laser lens, a brush extending outwardly from the first surface, and a recess in the first surface configured to receive at least a portion of the brush when the brush contacts the laser lens during a cleaning operation. Each brush is defined by a strand of material that includes opposite ends. A first end of the material extends through a first aperture to define a first brush and a second end extends through a second, spaced apart aperture to define a second brush. A middle portion of the strand of material extends along a second surface of the cleaning disc between the first and second apertures, and is covered by a cover.

Abstract: The present invention provides a filter for optical recording medium capable of preventing diffuse reflection of an information beam and a reference beam from a reflective layer in the optical recording medium and preventing occurrence of noise without causing shift in selective reflection wavelength, and distortion in a reproduced image even when an angle of incidence is changed, and an optical recording medium capable of recording a high density image by using the filter. Specifically, the present invention relates to the optical recording medium containing a first substrate, a recording layer which records information by utilizing holography, an optical compensation layer, a filter layer, and a second substrate, in this order, and the filter layer is a cholesteric liquid crystal layer.

Abstract: The present invention relates to a method and to an apparatus for manufacturing a record carrier having stored a content information in the form of a modulated bitstream 29 obtained from the content information by steps of encoding 21 and modulating 26. The record carrier has a number of dummy patterns at predetermined locations, allowing for the post-recording of secondary information, e.g. an individual code, whereby the secondary information is recorded by selectively modifying the dummy patterns. The method and apparatus according to the invention foresee that the modulated bitstream 29 with dummy patterns at the predetermined positions id obtained by inserting data word corresponding to the dummy patterns in a sequence of data words before the modulation takes place, so as to make sure that the dummy patterns are compliant with the modulation employed.

Abstract: Provided is a recording layer for optical information storage media, which not only excels in initial reflectivity and creativity of recording marks, but also extremely excels in durability under high temperature and high humidity conditions, and which can be adequately applied to next-generation optical discs using blue-violet laser. The recording layer for optical information storage media is a recording layer to create recording marks upon irradiation with a laser beam. This recording layer is composed of a tin-based alloy containing a total of 1.0 atomic percent or more and 15 atomic percent or less of at least one selected from neodymium (Nd), gadolinium (Gd), and lanthanum (La).

Abstract: [Problems] Multilayered optical information recording media involve a problem that a BCA is erroneously formed in a different information recording layer even if the BCA is intended to be formed in a specific information recording layer. [Means for Solving the Problems] An optical information medium (1) for recording/reproducing information by applying a laser beam includes two or more recording layers (11, 12) for recording/reproducing information by receiving a laser beam at the same laser beam incident surface (1a). A geometrical irregularity (K) is formed in an area (inner peripheral side) (21) for a BCA on one recording layer (12), and a mirror surface is formed in the area of the other information recording layer (11) corresponding to the BCA area (21). The geometrical irregularity (K) is detected when focus servo is actuated so as to detect the desired information recording layer. Thus, a BCA is prevented from being erroneously formed in another information recording layer.

Abstract: To provide a method for determining an optimum laser beam power for a single-side, dual-layer optical recording medium having first and second information layers, the method including: determining an optimum laser beam power based on a predetermined characteristic value at the time when the number of overwrite cycles on the recording medium is a predetermined value, wherein the method is conducted by an optical recording/reproduction apparatus utilizing optical change, and wherein the first information layer is closer to the laser irradiation side than is the second information layer.

Abstract: A recording layer is described that is at least partially or entirely positioned at a distance T7 of less than 0.4 mm with respect to the second surface. When the optical recording medium is clamped in a drive, the recording layer has a “higher” position than a recording layer of a known DVD. The layer structure of the described optical recording medium reduces the thickness of the disc in an area of the recording layer. In particular, a thickness T1 of only 0.4 to 0.7 mm is possible while maintaining the reliability of the optical recording medium (i.e. without reading problems in most or all drives). Further, the optical recording medium may have only one substrate, i.e. only one disc of polycarbonate, whereas the other side of the recording layer is only covered by a protective lacquer.

Abstract: The present invention is a BD-ROM having AVClips and PlayList information pieces, which are playback paths for the AVClips, recorded thereon. In addition, the BD-ROM also has multiple playback paths and dynamic scenarios recorded thereon. The dynamic scenarios instruct a playback device to play a digital stream using the playback paths. The dynamic scenarios include selection procedures (IF-statement blocks) which cause the playback device to compare a constant and a register-stored value indicating a user's age set on the playback device, (PSR(13)), and to select a playback path from among the multiple playback paths according to the result of the comparison.

Abstract: A recording medium (100) is provided with: an element layer including a semiconductor element (110) and an emission element (130), which emits light on the basis of an instruction from the semiconductor element; and a recording layer (120) in which readable predetermined data is recorded by irradiating a light beam.

Abstract: The optical recording medium comprises a visible information recording layer comprising at least two dyes of the following dyes. Ra1 to Rb3 each independently denote a hydrogen atom or a monovalent substituent, Ra2 and Ra3 may bond together to form a five to seven-membered heterocyclic ring, A denotes a substituted or unsubstituted aliphatic group, substituted or unsubstituted aryl group, or substituted or unsubstituted heterocyclic group, n denotes 0, 1, 2, or 3. Za21 and Za22 each independently denote an atom group forming an acidic nucleus, Ma21 to Ma23 each independently denote a substituted or unsubstituted methine group, Ka21 denotes an integer ranging from 0 to 3, and Q denotes a monovalent cation. A1=N—B1??General formula (III) A1 denotes a substituted or unsubstituted heterocyclic group, a substituted aliphatic group, or a substituted or unsubstituted carbocyclic group, and B1 denotes a substituted or unsubstituted heterocyclic group or a substituted or unsubstituted aryl group.

Abstract: The invention relates to a storage medium comprising a security feature, having a substrate (1, 4, 10), at least one functional layer (2, 5, 11), at least one feature which is written into the functional layer (2, 5, 11) and is visible when reflected and at least one feature which is written into the functional layer (2, 5, 11) and is visible when transmitted, at least one feature being individualized and at least one feature having a diffractive structure. The invention solves the technical problem of providing a larger variety of combinations of different security features. The invention also relates to a method for producing a storage medium comprising a security feature.

Abstract: An information recording medium includes a reproduction-dedicated area (160) where first recording information (60-1, etc.) is recorded in such a manner that its reproduction will not be disabled when it is reproduced, and a number-of-reproductions limit area (150) where second recording information (50-1, etc.) is recorded in such a manner that its reproduction will be disabled when a predetermined number of reproductions are performed. The second recording information (50-1, etc.) is correlated with the first recording information (60-1, etc.).

Abstract: An information recording carrier according to one embodiment has minute pattern including plural grooves or lands formed to be substantially in parallel and adjacent each other and comprises a supporting body having the minute pattern, a recording layer formed on the minute pattern formed on the supporting layer and a light transmission layer formed on the recording layer. The minute pattern is formed under a relation of P<?/NA, where a pitch of each groove or land is P, a wavelength of a laser beam is ? and a numerical aperture of an objective lens is NA. The plural grooves or lands have at least a wobbling region and data is recorded wobblingly in the wobbling region by frequency shift modulation. A phase relation between a high frequency portion and a low frequency portion composing the frequency shift modulation is ±(?/20.5) to ±(?/0.75). The data is also recorded wobblingly in the wobbling region by bi-phase modulation.

Abstract: Disclosed is an apparatus for reproducing main data under an optimum reproduction environment. The reproducing apparatus includes a readout unit (20) for reading out predetermined main data and spatial characteristic data, made up of the information on characteristics of a space in an environment different from the environment under which the main data is to be reproduced, from a recording medium (1) on which the main data and the spatial characteristic data have been recorded. The reproducing apparatus also includes a processing unit (25) for performing predetermined processing for reproduction of the main data, based on the spatial characteristic data read out by the readout unit (20).