Abstract: The present invention provides an optical information medium having excellent weather resistance and repeating characteristics. The optical information medium has a barrier layer between a protective layer and a recording layer. The barrier layer includes GeN or GeON, and at least one element selected from the group consisting of Al, B, Ba, Bi, C, Ca, Ce, Cr, Dy, Eu, Ga, H, In, K, La, Mn, N, Nb, Ni, Pb, Pd, S, Si, Sb, Sn, Ta, Te, Ti, V, W, Yb, Zn and Zr.

Abstract: An information recording medium having such a recording material layer on a substrate where reversible phase change between electrically or optically detectable states can be caused by electric energy or electromagnetic energy. The recording material forming the recording layer is either a material having a crystal structure including lattice defects in one phase of the reversible phase change or a material having a complex phase composed of a crystal portion including a lattice defect in one phase of the reversible phase change and an amorphous portion. Both portions contain a common element. A part of the lattice defects are filled with an element other than the element constituting the crystal structure. The recording medium having a recording thin film exhibits little variation of the recording and reproduction characteristics even after repetition of recording and reproduction, excellent weatherability, strong resistance against composition variation, and easily controllable characteristics.

Abstract: The present invention provides an optical information medium having excellent weather resistance and repeating characteristics. The optical information medium has a barrier layer between a protective layer and a recording layer. The barrier layer includes GeN or GeON, and at least one element selected from the group consisting of Al, B, Ba, Bi, C, Ca, Ce, Cr, Dy, Eu, Ga, H, In, K, La, Mn, N, Nb, Ni, Pb, Pd, S, Si, Sb, Sn, Ta, T, Ti, W, Yb, Zn and Zr.

Abstract: An information recording medium having such a recording material layer on a substrate where reversible phase change between electrically or optically detectable states can be caused by electric energy or electromagnetic energy. The recording material forming the recording layer is either a material having a crystal structure including lattice defects in one phase of the reversible phase change or a material having a complex phase composed of a crystal portion including a lattice defect in one phase of the reversible phase change and an amorphous portion. Both portions contain a common element. A part of the lattice defects are filled with an element other than the element constituting the crystal structure. The recording medium having a recording thin film exhibits little variation of the recording and reproduction characteristics even after repetition of recording and reproduction, excellent weatherability, strong resistance against composition variation, and easily controllable characteristics.

Abstract: An information recording medium having such a recording material layer on a substrate where reversible phase change between electrically or optically detectable states can be caused by electric energy or electromagnetic energy. The recording material forming the recording layer is either a material having a crystal structure including lattice defects in one phase of the reversible phase change or a material having a complex phase composed of a crystal portion including a lattice defect in one phase of the reversible phase change and an amorphous portion. Both portions contain a common element. A part of the lattice defects are filled with an element other than the element constituting the crystal structure. The recording medium having a recording thin film exhibits little variation of the recording and reproduction characteristics even after repetition of recording and reproduction, excellent weatherability, strong resistance against composition variation, and easily controllable characteristics.

Abstract: The present invention provides an optical information medium having excellent weather resistance and repeating characteristics. The optical information medium has a barrier layer between a protective layer and a recording layer. The barrier layer includes GeN or GeON, and at least one element selected from the group consisting of Al, B, Ba, Bi, C, Ca, Ce, Cr, Dy, Eu, Ga, H, In, K, La, Mn, N, Nb, Ni, Pb, Pd, S, Si, Sb, Sn, Ta, Te, Ti, V, W, Yb, Zn and Zr.

Abstract: An optical information recording medium including a first and second information layers is provided with an area where only the first information layer, which is provided nearer a substrate, exists, and initialization using a laser beam is started from this area. In an area where the second information layer exists, the first information layer is initialized after the second information layer is initialized. Alternatively, the first and second information layers are initialized at the same time by a flash light with adjusted emission time, emission energy, and the like. The first information layer is initialized after the second information layer is initialized by radiating a plurality of flash lights.

Abstract: The present invention provides an optical information recording medium having excellent characteristics in repetitive recording and a sufficient C/N ratio. The optical information recording medium includes a recording layer containing Ge, Te and Sb and a diffusion preventing layers in contact with the recording layer. A composition ratio of Ge, Te and Sb in the recording layer has numerical values which lie within the range represented by the area ABCDE in a ternary phase diagram of Ge, Te and Sb, where the points A, B, C, D and E are as follows: A (Ge50Te50), B (Ge22.5Sb22.0Te55.5), C (Ge17.0Sb41.5Te41.5), D (Ge48.0Sb26.0Te26.0), E (Ge65Te35) The diffusion layer contains at least one compound selected from an oxide, a nitride, a nitrogen oxide, a carbide and a fluoride.

Abstract: The present invention provides an optical information medium having excellent weather resistance and repeating characteristics. The optical information medium has a barrier layer between a protective layer and a recording layer. The barrier layer includes GeN or GeON, and at least one element selected from the group consisting of Al, B, Ba, Bi, C, Ca, Ce, Cr, Dy, Eu, Ga, H, In, K, La, Mn, N, Nb, Ni, Pb, Pd, S, Si, Sb, Sn, Ta, Te, Ti, V, W, Yb, Zn and Zr.

Abstract: An optical information recording medium of the present invention includes a transparent substrate and a multi-layered film formed on the transparent substrate. The multi-layered film includes a lower protective layer, a recording layer that changes reversibly between different states detectable optically by irradiation of light beams, an upper protective layer, an intermediate layer and a reflective layer in this order from the side near the transparent substrate. Of the upper protective layer, the intermediate layer and the reflective layer, the heat conductivity of the layer closest to the recording layer is the smallest of the three layers, and thereafter the heat conductivities of the others increase with increasing the distance from the recording layer, and the thickness of the recording layer is from 4 nm to 16 nm. In addition, a light absorption layer can be used in place of the intermediate layer.

Abstract: In a phase-change recording medium, a recording medium is provided with a barrier layer including Ge--N, Ge--N--O between a recording layer and a dielectric protective layer in order to prevent a chemical reaction and an atom diffusion between the recording layer and the dielectric protective layer. A barrier material can be also applied to the protective layer itself. Thereby, it is possible to considerably suppress a reduction of a reflectivity and a reduction of a signal amplitude due to the repeat of recording and erasing, such reductions being observed in a conventional phase-change optical information recording medium, and thereby the number of overwriting times can be increased.

Abstract: When a driving shaft rotates, a piston (9) revolves around the driving shaft in a cylinder room (6a) with supported by a swing bush (32) as a supporting point through a blade (31). Discharge ports (22) are formed in a front head (7) and a rear head (8) respectively and are disposed to be located in the proximity of the blade (31) and to communicate with a high pressure room. A semicircular portion of the discharge port (22) overlaps with the swing bush (32) and the cylinder (6). A pair of upper and lower cut parts (41) are each formed by cutting away an outer peripheral edge of the swing bush (32) and an inner peripheral edge of the cylinder (6) which are overlapped with the discharge port (22).

Abstract: In a method and an apparatus initializing an optical recording medium by irradiating a flash light. Walls are formed on a holder for holding the optical recording medium so as to adjoin an inner edge and an outer edge of the optical recording medium. When a flash light irradiates, a part of incident light which obliquely enters into an inner and an outer periphery regions of the optical recording medium is shaded by the walls. A quantity of the incident light incident on a unit area in each of the inner and outer periphery regions is less than that in a recording region between the inner and outer periphery regions. When temperature in the recording region reaches to an initializing temperature, the temperature in each of the inner and outer periphery regions is lower than the initializing temperature. So that neither cracks nor corrugations occur in a recording layer in the inner and outer regions.

Abstract: An optical recording medium capable of recording reproducing and erasing information wherein a pulsating phenomenon where dielectric layer provided on the top and bottom of the recording thing film layer are thermally expanded, and contracted through the recording.erasing so that an inferior phenomenon of moving the recording thin film layer along the guiding groove in the disc rotating direction is considerably restrained, whereby, uneven thickness in the recording thin film layer is removed, thus making it possible to prevent the signal quality from being deteriorated, and the repeating characteristics of the recording.erasing operations are exceptionally improved.

Abstract: The present invention relates to a production process and a production apparatus for the optical information recording media comprising a material thin film which exhibits a reversible change of the optical characteristics by the irradiation of an energy beam such as a laser beam on the substrate. By dropping the emission strength instantly to the virtual zero level after having the emission for a specified time in conducting the initial crystallization process, both a large irradiation power and a short irradiation time can be achieved to reduce the various thermal damages. The charging time can be shortened.

Abstract: On a substrate, a recording layer which reversibly transforms between two states with different optical properties--a crystalline phase and an amorphous phase--by the irradiation of a laser beam, a first and a second dielectric layer on the bottom and the top surfaces of the recording layer, and a third dielectric layer on one surface of the first or the second dielectric layers and on the opposite side with respect to the recording layer are successively laminated, thus preparing an optical information recording medium. The third dielectric layer has a smaller coefficient of thermal expansion than the first and the second dielectric layers, so that the thermal deformation of the first and the second dielectric layers is reduced and the mass transfer of the recording layer is controlled. As a result, the overwrite cycle characteristics of the optical information recording medium are excellent.

Abstract: An optical recording medium capable of recording, reproducing and erasing information wherein a pulsating phenomenon where dielectric layer provided on the top and bottom of the recording thing film layer are thermally expanded, and contracted through the recording and erasing so that an inferior phenomenon of moving the recording thin film layer along the guiding groove in the disc rotating direction is considerably restrained, whereby, uneven thickness in the recording thin film layer is removed, thus making it possible to prevent the signal quality from being deteriorated, and the repeating characteristics of the recording and erasing operations are exceptionally improved.

Abstract: In a phase change optical disk wherein a first heat-resistant protection layer, an optical active layer showing a reversible phase change between a crystal state and an amorphous state, and a second heat-resistant protection layer are laminated on a substrate in this order, both of the first and the second heat-resistant protection layers are made of a mixture of a chalcogenide and a vitrification accelerating material. Further, a mixture ratio of the vitrification accelerating material in the second heat-resistant protection layer is larger than that in the first heat-resistant protection layer. Thereby, it becomes possible that the first heat-resistant protection layer has the mixing ratio which gives the refractive index value bringing suitable optical properties, while the second heat-resistant protection layer has the different mixing ratio which gives the thermal conductivity bringing suitable thermal properties.

Abstract: In a record medium wherein information is recorded and/or erased by changing the optical state thermally by the irradiation with a laser beam or the like, a protection layer made from a material having a larger thermal conductivity than adjacent protection layers is used to decrease the temperature difference between the center and edges of a record mark on recording and/or erasing with a laser beam. By using the material having a larger thermal conductivity, the heat due to the irradiation with a laser beam or the like is diffused not only to the periphery of the substrate, but also to the plane of the substrate surely. Therefore, the temperature difference between the center and the edges in a mark on irradiation with the laser beam is decreased, and the recording/erasing characteristics and the power margin for erasing can be improved.

Abstract: An optical information recording medium is provided in which the active layer is a phase change material capable of absorbing energy and being converted between a substantially amorphous state and a substantially crystalline state. The active layer contains nitrogen, which may be in the form of a nitride or nitrides of the constituent elements of the active layer, or may be a nitrided surface thereof. The inclusion of nitrogen inhibits localized shifting of the active material, which leads to degradation of the recording/erase properties of the medium. The optical recording medium includes a substrate, onto which is deposited in sequence a first dielectric layer, a nitrogen-containing active layer, a second dielectric layer, and a metallic reflecting layer. The second dielectric layer is made thin, so that the cooling rate of the active layer is increased to form a more uniform amorphous state.