Abstract: An optical recording medium includes a plurality of information signal layers, and at least one of the plurality of information signal layers other than the farthest information signal layer from a light irradiation surface includes: a recording layer; a first dielectric layer provided on a side opposite to a light incident side of the recording layer; and a second dielectric layer provided on the light incident side of the recording layer. The first dielectric layer and the second dielectric layer include indium oxide and tin oxide, and the atomic concentration of tin in the first dielectric layer is higher than the atomic concentration of tin in the second dielectric layer.

Abstract: An optical recording medium includes a plurality of information signal layers, and at least one of the plurality of information signal layers other than the farthest information signal layer from a light irradiation surface includes: a recording layer; a first dielectric layer provided on a side opposite to a light incident side of the recording layer; and a second dielectric layer provided on the light incident side of the recording layer. The first dielectric layer and the second dielectric layer include indium oxide and tin oxide, and the atomic concentration of tin in the first dielectric layer is higher than the atomic concentration of tin in the second dielectric layer.

Abstract: An optical recording medium includes: a substrate having a first principal surface and a second principal surface; one or plural information signal layers formed on the first principal surface of the substrate for undergoing recording or reproduction of information signals upon irradiation with light; and a barrier layer formed on the second principal surface of the substrate for suppressing the gas release from the second principal surface of the substrate, wherein an area of a region exposing from the barrier layer of the second principal surface of the substrate is not more than 688 mm2.

Abstract: Recording and reproducing characteristics and data saving reliability are secured in a write-once two-layer recording medium. A second recording layer from a side irradiated with light for recording and reproduction includes organic dye shown by a general formula of a chemical formula 3 described below (in the formula, R1 and R2 are alkyl groups of carbon number 1 to 4; Y1, Y2 respectively are organic groups independently; and X is Cl04, BF4, PF6, SbF6), and organic dye shown by a general formula of a chemical formula 4 described below (in the formula, R1, R4 are alkyl groups of carbon number 1 to 4; R2, R3 are alkyl groups of carbon number 1 to 4 or groups forming 3 to 6 membered rings by being coupled; Y1, Y2 respectively are organic groups independently; and X is Cl04, BF4, PF6, SbF6), to secure durability.

Abstract: Disclosed is to provide with an optical recording medium of a write-once type in which an excellent recording characteristic can be obtained over low speed recording to high speed recording.

Abstract: A recording medium is provided and includes; a substrate having a first area formed with a first groove and a second area formed with a second groove, at least one information layer provided on the substrate, and a protecting layer provided on the information layer. Predetermined binary information has previously been recorded on the first groove and the first groove is shallower or narrower than the second groove.

Abstract: An optical recording medium includes: a substrate having a first principal surface and a second principal surface; one or plural information signal layers formed on the first principal surface of the substrate for undergoing recording or reproduction of information signals upon irradiation with light; and a barrier layer formed on the second principal surface of the substrate for suppressing the gas release from the second principal surface of the substrate, wherein an area of a region exposing from the barrier layer of the second principal surface of the substrate is not more than 688 mm2.

Abstract: Recording and reproducing characteristics and data saving reliability are secured in a write-once two-layer recording medium. A second recording layer from a side irradiated with light for recording and reproduction includes organic dye shown by a general formula of a chemical formula 3 described below (in the formula, R1 and R2 are alkyl groups of carbon number 1 to 4; Y1, Y2 respectively are organic groups independently; and X is ClO4, BF4, PF6, SbF6), and organic dye shown by a general formula of a chemical formula 4 described below (in the formula, R1, R4 are alkyl groups of carbon number 1 to 4; R2, R3 are alkyl groups of carbon number 1 to 4 or groups forming 3 to 6 membered rings by being coupled; Y1, Y2 respectively are organic groups independently; and X is ClO4, BF4, PF6, SbF6), to secure durability.

Abstract: A recording medium is provided and includes; a substrate having a first area formed with a first groove and a second area formed with a second groove, at least one information layer provided on the substrate, and a protecting layer provided on the information layer. Predetermined binary information has previously been recorded on the first groove and the first groove is shallower or narrower than the second groove.

Abstract: An optical recording medium comprises a transmission substrate and a recording layer formed on the transmission substrate, the recording layer containing at least a dye material expressed by a general formula shown at the following chemical formula (in the chemical formula 1, R1 represents alkyl group having carbon numbers 1 to 4, R2, R3 represent alkyl group having carbon numbers 1 to 4, benzyl group or groups combined to form 3 to 6 rings, Y1 and Y2 independently represent organic groups and X represent ClO4, BF4, PF6, SbF6) and a dye material expressed by a general formula represented by the following chemical formula 2(in the chemical formula 2, R1 and R2 represent alkyl groups having carbon numbers 1 to 4, benzyl groups or groups combined to form 3 to 6 rings, Y1, Y2 independently represent organic groups and X represent ClO4, BF4, PF6, SbF6): In a write once type optical recording medium such as DVD?R and DVD+R, satisfactory recording characteristics can be obtained from low-speed recording to high-

Abstract: Disclosed is to provide with an optical recording medium of a write-once type in which an excellent recording characteristic can be obtained over low speed recording to high speed recording.

Abstract: An optical recording medium comprises a transmission substrate and a recording layer formed on the transmission substrate, the recording layer containing at least a dye material expressed by a general formula shown at the following chemical formula (in the chemical formula 1, R1 represents alkyl group having carbon numbers 1 to 4, R2, R3 represent alkyl group having carbon numbers 1 to 4, benzyl group or groups combined to form 3 to 6 rings, Y1 and Y2 independently represent organic groups and X represent ClO4, BF4, PF6, SbF6) and a dye material expressed by a general formula represented by the following chemical formula 2(in the chemical formula 2, R1 and R2 represent alkyl groups having carbon numbers 1 to 4, benzyl groups or groups combined to form 3 to 6 rings, Y1, Y2 independently represent organic groups and X represent ClO4, BF4, PF6, SbF6): In a write once type optical recording medium such as DVD?R and DVD+R, satisfactory recording characteristics can be obtained from low-speed recording to high-s

Abstract: The present invention provides an optical recording medium including as a recording layer an organic pigment film containing an organic pigment. The organic pigment film contains as the organic pigment at least a compound exhibiting a heat generating reaction. This enables to realize a stable recording even with a low-power laser beam while maintaining a high reflection factor of the recording layer.

Abstract: A recording layer 6 records and stores information and comprises a plurality of layers, namely a first layer 6a and a second layer 6b. The first layer 6a is made from a recording material which gives parallel directions to saturation magnetization and sublattice magnetization. The second layer 6b is made from a recording material which gives antiparallel directions to saturation magnetization and sublattice magnetization at room temperature. The recording material for the second layer 6b gives parallel directions to saturation magnetization and sublattice magnetization at around a read temperature.

Abstract: To stably perform optical recording and optical reproducing under optimum conditions, in an optical recording medium having a writable recording layer on a substrate and having a maker recording area in which recording is performed by a maker on the recording layer, individual drive control information of the optical recording medium is recorded in the maker recording area, and, in optical recording and optical reproducing, optical recording and optical reproducing are performed by the drive control information under optimum conditions.

Abstract: In order too simplify the manufacturing process for a CAD magneto-optical recording medium and reduce the cost therefor, there is provided a magnetically induced super resolution-type magneto-optical recording medium which comprises, on a light-transmitting substrate, at least a recording layer for recording and retaining information therein, and a read-out layer for copying therein the information retained in the recording layer during reproduction of the information, wherein the magneto-optical recording medium has an exchange-coupling breaking layer between the recording layer and the read-out layer, wherein the exchange-coupling breaking layer comprises a layer of a nitride of either one of GdFeCo or TbFeCo.

Abstract: To stably perform optical recording and optical reproducing under optimum conditions, in an optical recording medium having a writable recording layer on a substrate and having a maker recording area in which recording is performed by a maker on the recording layer, individual drive control information of the optical recording medium is recorded in the maker recording area, and, in optical recording and optical reproducing, optical recording and optical reproducing are performed by the drive control information under optimum conditions.

Abstract: A recording layer 6 records and stores information and comprises a plurality of layers, namely a first layer 6a and a second layer 6b. The first layer 6a is made from a recording material which gives parallel directions to saturation magnetization and sublattice magnetization. The second layer 6b is made from a recording material which gives antiparallel directions to saturation magnetization and sublattice magnetization at room temperature. The recording material for the second layer 6b gives parallel directions to saturation magnetization and sublattice magnetization at around a read temperature.

Abstract: In a magneto-optical recording medium including a first magnetic layer which is magnetized in a predetermined direction according to a data signal and a second magnetic layer which is magnetically connected to the first magnetic layer by exchange interaction, so that a boundary magnetic wall can exist between the first magnetic layer and the second magnetic layer, the present invention increases stability of the boundary magnetic wall formed between the first magnetic layer and the second magnetic layer and to enhance a reproduction durability as well as durability against repeated recording.The first magnetic layer and the second magnetic layer are formed by sputtering. At least one of the magnetic layers composing the first magnetic layer and positioned adjacent to the second magnetic layer is formed with a sputter gas pressure greater than the sputter gas pressure applied when forming a magnetic layer composing the second magnetic layer and positioned adjacent to the first magnetic layer.

Abstract: This invention provides a method for producing a magneto-optical recording medium with a laminated film composed of a plurality of magnetic layers made of alloys of rare earth metals-transition metals such as a magneto-optical recording medium allowing direct overwriting through light intensity modulation and a magneto-optical recording medium allowing magnetically induced recording with super resolution, or a method for stably producing a magneto-optical recording medium excellent in performance.The method consists of using, as vaporizers to form the laminated magnetic film, three or more vaporizers including one or more vaporizers containing mainly rare earth elements and one or more vaporizers containing mainly transition metals.