Abstract: A copper-based catalyst precursor capable of achieving a high conversion ratio and high selectivity in the isomerization reaction of a ?,?-unsaturated alcohol portion and a method for producing the same and to provide a hydrogenation method in which the copper-based catalyst precursor is used are provided. Specifically, a copper-based catalyst precursor obtained by calcining a mixture containing copper, iron, aluminum, and calcium silicate in which an atomic ratio of iron and aluminum to copper [(Fe+Al)/Cu] is in a range of 1.71 to 2.5, an atomic ratio of aluminum to iron [Al/Fe] is in a range of 0.001 to 3.3, and calcium silicate is contained in a range of 15% by mass to 65% by mass at a temperature in a range of 500° C. to 1,000° C. and a hydrogenation method in which the copper-based catalyst precursor is used are provided.

Abstract: A single disc is configured to deal with both HD DVD information and DVD information. This invention has the following basic elements (1) a single-sided dual layer optical disc where a light transmission layer, a first recording layer accessed with a first laser beam, an space layer, and a second recording layer accessed with a second laser beam are arranged in that order in the direction in which a laser beam enters, (2) the areal recoding density of the second recording layer is three times or more that of the first recording layer, (3) information indicating that the second recording layer has been formed is formed in the first recording layer, and (4) information indicating that the first recording layer has been formed is formed in the second recording layer.

Abstract: An information recording apparatus comprises an encryption section encrypting contents information and also a license condition referred to to limit use of the contents information and a decoding key for decoding the encrypted contents information to generate license information, and a recording section recording the encrypted contents information and the generated license information on a recording medium. An information reproducing apparatus comprises a decoder unit decoding the license information recorded on the recording medium using a second decoding key for decoding the license information and deciding on the basis of the license condition contained in the decoded license information whether the contents information can be used. If it is decided that the contents information can be used, the encrypted contents information recorded on the recording medium is decoded using the first decoding key contained in the decoded license information.

Abstract: A single-sided dual-layer optical disc comprising an optically transparent layer; a first recording layer accessed by a first laser beam; an intermediate layer; and a second recording layer accessed by a second laser beam, wherein the optically transparent layer, the first recording layer, the intermediate layer, and the second recording layer are sequentially disposed in a laser beam incidence direction, wherein a thickness of the optically transparent layer, which is a distance from a light incident surface to the first recording layer, is 550 to 575 ?m, wherein a thickness of the intermediate layer, which is a distance between the first and second recording layers, is 29 to 47 ?m, and wherein a surface recording density of the second recording layer is at least 3 times that of the first recording layer.

Abstract: An optical disc is based on the following the distance of the light transmission layer from a light incidence plane to the first recording layer is a minimum of 550 ?m. The distance between the first and the third recording layer is a maximum of 72 ?m. The distance between the second and the third recording layer is a minimum of 15 ?m. The distance between the first and the second recording layer is about 31 to 40 ?m. The reflectivities of the first and the second recording layer with respect to the first laser beam are 18% or more, and the ratio between the reflectivities is about 1.15 or less. The areal recording density of the third recording layer is three times or more as high as the areal recording density of the first and the second recording layer.

Abstract: According to one embodiment, an optical disc is the following the distance between a light incidence plane and the first recording layer is a minimum of 550 ?m. The distance between the first and the third recording layer is a maximum of 72 ?m. The distance between the second and the third recording layer is a minimum of 15 ?m. The distance between the first and the second recording layer is about 31 to 40 ?m. The reflectivities of the first and the second recording layer with respect to the first laser beam range from 18 to 27%, and the ratio therebetween is about 1.1 or less. The reflectivity of the third recording layer is below about 6%. The areal recording density of the third recording layer is three times or more as high as that of the first recording layer and the second recording layer.

Abstract: An optical disc of this invention is configured to be capable of dealing with both information in HD DVD and information in DVD.

Abstract: An information recording apparatus comprises an encryption section encrypting contents information and also a license condition referred to to limit use of the contents information and a decoding key for decoding the encrypted contents information to generate license information, and a recording section recording the encrypted contents information and the generated license information on a recording medium. An information reproducing apparatus comprises a decoder unit decoding the license information recorded on the recording medium using a second decoding key for decoding the license information and deciding on the basis of the license condition contained in the decoded license information whether the contents information can be used. If it is decided that the contents information can be used, the encrypted contents information recorded on the recording medium is decoded using the first decoding key contained in the decoded license information.

Abstract: User data recording areas and intermediate areas are alternately arranged on a disk. The intermediate area records at least information for synchronization.

Abstract: One embodiment of the present invention is based on the following (1) An optical disc has a triple layer structure in which there are a light transmission layer, a first recording layer which is accessed with a first laser beam, and a second recording layer and a third recording layer which are accessed with a second laser beam. (2) The distance of the light transmission layer from a light incidence plane to the first recording layer is a minimum of 550 ?m. (3) The distance between the first recording layer and the third recording layer is a maximum of 72 ?m. (4) The distance between the second recording layer and the third recording layer is a minimum of 19 ?m. (5) The distance between the first recording layer and the second recording layer is about 28 to 38 ?m.

Abstract: User data recording areas and intermediate areas are alternately arranged on a disk. The intermediate area records at least information for synchronization.

Abstract: An optical disc is based on the following the distance of the light transmission layer from a light incidence plane to the first recording layer is a minimum of 550 ?m. The distance between the first and the third recording layer is a maximum of 72 ?m. The distance between the second and the third recording layer is a minimum of 15 ?m. The distance between the first and the second recording layer is about 31 to 40 ?m. The reflectivities of the first and the second recording layer with respect to the first laser beam are 18% or more, and the ratio between the reflectivities is about 1.15 or less. The areal recording density of the third recording layer is three times or more as high as the areal recording density of the first and the second recording layer.

Abstract: According to one embodiment, an optical disc is the following the distance between a light incidence plane and the first recording layer is a minimum of 550 ?m. The distance between the first and the third recording layer is a maximum of 72 ?m. The distance between the second and the third recording layer is a minimum of 15 ?m. The distance between the first and the second recording layer is about 31 to 40 ?m. The reflectivities of the first and the second recording layer with respect to the first laser beam range from 18 to 27%, and the ratio therebetween is about 1.1 or less. The reflectivity of the third recording layer is below about 6%. The areal recording density of the third recording layer is three times or more as high as that of the first recording layer and the second recording layer.

Abstract: An optical disc of this invention is configured to be capable of dealing with both information in HD DVD and information in DVD.

Abstract: This invention enables a single disc to deal with HD DVD information and DVD information. An optical disc according to the present invention is basically specified by the following items (1) the optical disc is a single-sided dual layer optical disc, (2) the distance in the light transmission layer from an incidence plane to a first recording layer is 578 to (578+2p) ?m (2p is the maximum value of substrate thickness accuracy), (3) the distance in the space layer between the first recording layer and a second recording layer is (62?2p?2q) to (62?2p) ?m (2q is the maximum value of space layer thickness accuracy), and (4) the areal recording density of the first recording layer is three times or more as high as that of the second recording layer.

Abstract: A single-sided dual layer optical disc of the invention comprises a first light transmission layer, a first recording layer which is accessed with a first laser beam, a second light transmission layer, and a second recording layer which is accessed with a second laser beam, these layers being arranged in that order from an incidence plane in the direction of incidence, the distance from the incidence plane to the second recording layer being 570 to 630 Am, and the areal recording density of the first recording layer being five times or more as high as that of the second recording layer.

Abstract: A single disc is configured to deal with both HD DVD information and DVD information. This invention has the following basic elements (1) a single-sided dual layer optical disc where a light transmission layer, a first recording layer accessed with a first laser beam, an space layer, and a second recording layer accessed with a second laser beam are arranged in that order in the direction in which a laser beam enters, (2) the areal recoding density of the second recording layer is three times or more that of the first recording layer, (3) information indicating that the second recording layer has been formed is formed in the first recording layer, and (4) information indicating that the first recording layer has been formed is formed in the second recording layer.

Abstract: A single-sided dual-layer optical disc comprising an optically transparent layer; a first recording layer accessed by a first laser beam; an intermediate layer; and a second recording layer accessed by a second laser beam, wherein the optically transparent layer, the first recording layer, the intermediate layer, and the second recording layer are sequentially disposed in a laser beam incidence direction, wherein a thickness of the optically transparent layer, which is a distance from a light incident surface to the first recording layer, is 550 to 575 ?m, wherein a thickness of the intermediate layer, which is a distance between the first and second recording layers, is 29 to 47 ?m, and wherein a surface recording density of the second recording layer is at least 3 times that of the first recording layer.

Abstract: An information recording medium has a plurality of stacked recording layers. Each recording layer has a spiral track which defines a plurality of rounds, and at least one index header aligned in the radial direction of the disk to partially intercept the spiral track. The index header has address data of each round of the spiral track, which is formed by embossed pits, and some or all of the index headers of the first and second recording layers are laid out to overlap each other when viewed from the predetermined surface.

Abstract: A disk-shaped information recording medium has spiral tracks in which land- and groove-shaped tracks are alternately switched in units of rounds, and one index header which is aligned in the radial direction of a disk and is allocated at only the boundary between the land- and groove-shaped tracks.