Abstract: The present invention relates to an optical recording media including two or more information layers, at least one of the information layers including a writable recording film. In the optical recording media, at least one information layer has protrusions and recesses that permit tracking and at least another one information layer is substantially flat.

Abstract: According to one embodiment, a recordable information recording medium includes an organic dye layer contains an organic dye including a cation portion having monomethinecyanine and an anion portion having an azo metal complex, and a quencher having a formazan metal complex.

Abstract: According to one embodiment, a write-once information recording medium includes a transparent resin substrate having concentric or spiral grooves and lands, and a recording film formed on the grooves and lands of the transparent resin substrate, wherein the recording film includes an organic dye layer containing a metal complex monomer and a metal complex polymer, a recording mark is formed in the organic dye layer by emission of a short-wavelength laser beam, and a light reflectance of the recording mark formed by emission of the short-wavelength laser beam is higher than that before emission of the short-wavelength laser beam, and the grooves wobble within a predetermined amplitude range.

Abstract: According to one embodiment, a write-once type information storage medium using a recording material which has a low to high characteristic that a light reflectivity in a recording mark increases with respect to a non-recording area and which has a recording characteristic in accordance with a principle of recording without substrate deformation, wherein the recording material includes at least an organic metal complex, and wherein the organic metal complex includes a center metal.

Abstract: According to one embodiment, an information storage medium includes an organic dye material which records information with a light beam having a wavelength equal to or smaller than 620 nm.

Abstract: According to one embodiment, an information recording medium includes a transparent resin substrate having concentric grooves and concentric lands or a spiral groove and spiral land, and a recording layer formed on the groove and land, and capable of recording and reproducing information by using a semiconductor laser of 450 nm or less. When reproducing recorded information, the information recording medium satisfies the following formula (1) 0.87?M4×/M1×?1.

Abstract: An optical disk having a recording layer on a substrate, a bonding layer which is made of an ultraviolet cured resin bonding the recording layer, a transparent layer which is bonded to the bonding layer, and an overcoating layer which is formed on the transparent sheet and is made of the ultraviolet cured resin further has a mixed layer which is formed by mixing the ultraviolet cured resins of the bonding layer and the overcoating layer. Consequently, the bonding layer, the overcoating layer, and the mixed layer are integrally cured, so that the substrate is entirely covered with the ultraviolet cured resin having transparency, which allows a light transmitting layer A to be protected with sufficient strength.

Abstract: An optical disk having a recording layer on a substrate, a bonding layer which is made of an ultraviolet cured resin bonding the recording layer, a transparent layer which is bonded to the bonding layer, and an overcoating layer which is formed on the transparent sheet and is made of the ultraviolet cured resin further has a mixed layer which is formed by mixing the ultraviolet cured resins of the bonding layer and the overcoating layer. Consequently, the bonding layer, the overcoating layer, and the mixed layer are integrally cured, so that the substrate is entirely covered with the ultraviolet cured resin having transparency, which allows a light transmitting layer A to be protected with sufficient strength.

Abstract: According to one embodiment, an information recording medium including a recording film using an organic recording material recorded by recording light having a wavelength of 405 nm and an organic recording material whose light reflection quantity varies by reproducing light having a wavelength of 650 nm for a recording layer and an optical reflection layer and a land sandwiched between a pre-groove having an irregular shape and an adjoining pre-groove is provided on an interface between the recording layer and the optical reflection layer.

Abstract: According to one embodiment, an information recording medium has a plurality of recording layers, and records and reproduces information by using a semiconductor layer of 450 nm or less. When reproducing information, letting x be the frequency of repetitive recording of a shortest mark length and shortest space length of the information, the ratio of the value of a highest level to the value of a level at x/190 of a sum signal detected within the frequency range of x/3240 to x/190 is lower than 32 dB, or the ratio of the average value of the amplitudes of signals of repetitive recording of the shortest mark length and shortest space length to the value of the highest level within the frequency range of x/3240 to x/190 is higher than 10 dB.

Abstract: According to one embodiment, an optical information recording medium includes pre-grooves with an irregular shape and lands each of which is sandwiched between the pre-grooves adjacent to each other, where the pre-grooves and lands are defined on an interface between a recording layer and a light reflection layer in a recording film, where the recording film includes a light reflectivity that enables reproduction with light of 650±5 nm, the recording layer includes a recording sensitivity with respect to light by a wavelength shorter than 650±5 nm, and a recording mark can be formed on the pre-groove by using light with a wavelength shorter than 650±5 nm.

Abstract: According to one embodiment, when recording information by using a semiconductor laser at 450 nm or less, an information recording medium satisfies 9.5×10?8??/(X*NA)?4.6×10?8 (where X is the linear recording velocity, ? is the laser wavelength, and NA is the numerical aperture).

Abstract: In an optical disk of the invention composed of two substrates bonded to each other, the level of double refraction is set to 60 nm or less in a read-only disk, to 60 nm or less in a write-once type disk, and to 40 nm or less in a rewritable type disk, respectively.

Abstract: According to one embodiment, an information storage medium has a substrate, a first recording layer containing an organic dye material, a first barrier layer, a spacer layer, a second recording layer, a second barrier layer, and a protective layer formed on the second barrier layer. The angle that the outer side surface and inner side surface of the protective layer make with a direction parallel to the surface of the second barrier layer is 30° to 150°, at least one of the first and second barrier layers has lands and grooves on its two major surfaces and the depth of the lands on one major surface is smaller than that of the lands on the other major surface close to the substrate, or the first and second barrier layers are made of a material formable by coating.

Abstract: According to one embodiment, there is disclosed an information recording medium which includes a first information layer formed on a transparent substrate having tracks of a concentric or spiral shape, and a second information layer formed on the first information layer, and allows optical recording and playback from one surface, and in which eccentricity amounts of the tracks of the information layers fall within the range from 0 to 70 ?m.

Abstract: According to one embodiment, an information recording medium has two or more recording layers, the track pitch falls within the range from 250 to 500 nm, and the half maximum full-width of the groove of the substrate falls within the range from 47.5% to 72.5%.

Abstract: An optical disk having a recording layer on a substrate, a bonding layer which is made of an ultraviolet cured resin bonding the recording layer, a transparent layer which is bonded to the bonding layer, and an overcoating layer which is formed on the transparent sheet and is made of the ultraviolet cured resin further has a mixed layer which is formed by mixing the ultraviolet cured resins of the bonding layer and the overcoating layer. Consequently, the bonding layer, the overcoating layer, and the mixed layer are integrally cured, so that the substrate is entirely covered with the ultraviolet cured resin having transparency, which allows a light transmitting layer A to be protected with sufficient strength.

Abstract: According to one embodiment, in an information recording medium in which letting H1 (nm) a groove depth of a first substrate on which a first recording layer is formed, H2 (nm) a groove depth of a second substrate on which a second recording layer is formed, H11 (nm) a thickness of a first dye layer at a land area, H12 (nm) a thickness of the first dye layer at a groove bottom area, H21 (nm) a thickness of a second dye layer at a land area, and H22 (nm) a thickness of the second dye layer at a groove bottom area, the groove depth H1 of the first substrate and the groove depth H2 of the second substrate satisfy |H11?H12|=?, |H21?H22|=?, ?/8n?H1????/3n, and ?/8n?H2????/3n.

Abstract: According to one embodiment, a first recording film, interlayer, and second recording film are formed on a transparent resin substrate having a groove and land. A recording mark is formed by irradiation with a short-wavelength laser beam. The light reflectance of the recording mark formed by irradiation with the short-wavelength laser beam is higher than a light reflectance before irradiation with the short-wavelength laser beam. The first recording film has a first read-only recording mark recorded by a three-dimensional pit. The second recording film has a second read-only recording mark recorded by a three-dimensional pit. The reflectances of the pits of the first and second recording layers are 4.2% to 8.4%, or the pit width of the second recording film is larger than that of the first recording layer.

Abstract: According to one embodiment, an information recording medium has two or more recording layers, the track pitch falls within the range from 250 to 500 nm, and the half maximum full-width of the groove of the substrate falls within the range from 47.5% to 72.5%.