Abstract: Phase-change type, reversible optical information recording medium, being possible for recording, reproducing, erasing, and rewriting of information, by use of a laser beam. This invention consists of recording thin film of ternary elements, for example, containing Ge, Te, Sb/or Bi or quaternary elements containing the fourth element of Se with which a part of Te is replaced, which is established on such surface—flat substrates as glass or plastics. In this case, the component ratio of Te and Se is selected not to be excess for other elements, such as Ge, Sb/or Bi so as to be fixed as stable compounds of stoichiometric compositions of GeTe, Sb2Te3/or Bi2Te3, or GeSe, Sb2Se3/Bi2Se3 when crystallized. Strictly speaking, a concentration of each component is selected to have proper ratio of the number of atomes each other so as to represent whole composition as the sum of each component. By this treatment, it is possible to have high crystallization speed and long cyclability of recording/erasing.

Abstract: An information recording medium includes a substrate, a first protective layer formed on the substrate, a recording layer formed on the first protective layer, and a second protective layer formed on the recording layer. The first protective layer has a thickness in a range from 65 nm to 130 nm. The second protective layer has a thickness in a range from 15 nm to 45 nm. The recording layer has a thickness in a range from 15 nm to 35 nm and is composed of a phase-change alloy with the composition in terms of atomic percentage being represented by the formula AgaInbSbcTed where 0<a<6, 3≦b≦15, 50≦c≦65, 20≦d≦35, a+b+c+d=100. The information recording medium is configured to provide capabilities of reading, writing and overwriting of information at linear rotation rates ranging from 1.2 m/s to 11.2 m/s.

Abstract: The optical recording medium of this invention includes: a first substrate having a first information surface; a semitransparent reflection film formed on the first information surface of the first substrate; a second substrate having a second information surface; a reflection film formed on the second information surface of the second substrate; and an adhesive layer for adhering the first substrate and the second substrate so that the first information surface and the second information surface face each other, wherein the thickness of the first substrate is 0.56 mm or more, the thickness of the adhesive layer is 30 &mgr;m or more, and the total thickness of the first substrate and the adhesive layer is 0.68 mm or less.

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: An optical information recording medium comprising a thin plastic substrate of 0.6 mm or thinner, wherein the substrate is protected against strain without being limited by a film structure and a film formation condition. A single-layer or multilayer thin film (70) is formed on a plastic disk-like substrate having a center hole (10). This thin film (70) has a strain relief area (72) inside a recording area (71). This strain relief area (72) is formed by setting an outer diameter of an undeposited inner portion (5) to a value satisfying the following formula (1), for example: A0≦AX≦−0.172P+0.163 where A0: diameter of center hole, AX: outer diameter of undeposited inner portion, P: total strain occurring in thin film when film depositing.

Abstract: A half-transmissive film of an optical disk is formed using a Cu oxide instead of Au, while achieving similar reflectivity characteristics to those of Au. Alternatively, the half-transmissive film may comprise a compound of Cu with a corrosion-resistant material, or a stack of layers comprising a lower layer film of Cu, Ag, or Al and an upper layer film of a corrosion-resistant material. Further, the half-transmissive film may comprise ZnS.SiO2, a nitride of Ti, indium-tin-oxide, or an alloy of Au and Cu or a compound including Au and Cu.

Abstract: A rewritable optical information medium includes a substrate coated with two carbide layers, a phase-change recording layer between two carbide layers, and a light-absorptive layer of a material like Si, Ge, Mo, or W to slow the cooling when scanned with laser light so that the medium can be used for high data rate recording. The material is capable of a user data bit rate of 50 Mbit/s.

Abstract: An optical recording medium comprising, in the following order, a substrate, a reflecting layer, a lower dielectric layer, an optical recording layer, the optical recording layer recording information by means of change in a physical property of the optical recording layer which is generated by an applied light beam, the change in a physical property of the optical recording layer being conducted at an operating temperature, and an upper dielectric layer, wherein the substrate has a thermal deformation temperature lower than the operating temperature and the optical recording medium further comprises a thermally insulating layer between the substrate and the reflecting layer.

Abstract: The present invention relates to an optical recording medium having a protective layer and a phase-change recording layer on a substrate, said protective layer containing a metallic oxysulfide and an optical recording medium having a protective layer and a phase-change recording layer, said protective layer being formed by sputtering using a target comprising a metallic oxysulfide.

Abstract: An optical molding material which is an aromatic polycarbonate resin pellet, wherein the amount of fine powders, produced from 5 kg of the pellets mixed in a vessel for 1 hour and having a particle diameter of 1.0 mm or less, is 300 ppm or less. The formation of carbide during molding can be suppressed by using the pellets of the present invention.

Abstract: The present invention provides an optical disc capable of effectively reducing a reproduction signal jitter value and obtaining a wider record power margin assuring a reproduction limit jitter value to obtain a preferable recording/reproduction characteristic even after a number of times of recording repeated. The optical disc includes the following films successively formed on a substrate 2: a first dielectric film 3; a phase change recording film 4 whose phase is changed between a crystalline state and an amorphous state thereby to record an information signal; a second dielectric film 5; and a light reflection film formed on the phase change recording film 4 and constituted by an Al alloy containing Cu in a range from 0.1 to 1.0 atomic %.

Abstract: A phase change optical recording medium has on a substrate a recording layer consisting essentially of a Sb base thin film and a reactive thin film. The Sb base thin film is formed by depositing a Sb base material containing at least 95 at % of Sb to a thickness of 70-150 Å. The reactive thin film is formed of a material which forms a phase change recording material when mixed with Sb. The reactive thin film is typically formed of an In—Ag—Te or Ge—Te material. Stable write/read characteristics are accomplished at the first overwriting, initializing operation is eliminated, and rewriting is impossible at the same linear velocity as recording.

Abstract: The object is to hold the recording, reproduction and rewrite characteristics better than in the prior art. An information recording medium comprises an information recording thin film as a recording layer formed on a substrate for recording and/or reproducing information by the change in the atomic arrangement caused by the radiation of light. The medium further comprises at least one protective layer. The protective layer and the recording layer are formed in that order from the light incidence side, followed by forming at least one absorption control layer, thereby exhibiting a superior rewrite characteristic.

Abstract: An information storage medium includes a substrate, a thin film formed on the substrate and having a reflectance changed by a phase change caused by irradiation of an energy beam irradiated via the substrate and a first reflective layer and a second reflective layer on the film directly or via an intermediate layer. The thin film includes one of In3SbTe2, In35Sb32Te33, In31Sb26Te43 and Ag—In—Sb—Te. The first reflective layer and the second reflective layer are piled up in the recited order from a thin film side with the first reflective layer consisting of a material having an attenuation factor k of 2 or less and selected from a group of silicon based materials and the second reflective layer consisting of a material having an attenuation factor k of at least 3.

Abstract: A recording medium includes a transparent substrate; a crystalline phase-change layer provided over the transparent substrate; a dielectric layer provided over the phase-change layer; a metallic reflector layer provided over the dielectric layer; and the crystalline phase-change layer having a thickness and phase-change material selected so that data can be recorded in it on a first write, but on second or subsequent writes the written data results in at least a 50% increase in data jitter.

Abstract: An optical information recording medium includes a substrate with guide grooves thereon, a recording layer provided on the substrate, including a recording material of which phase is reversibly changeable from a stable state to a semistable state and vice versa, a heat-resistant dielectric protective layer provided on the recording layer, including a protective material which includes Zn, Si, S and O, and a light reflection and heat dissipation layer provided on the heat-resistant dielectric protective layer.

Abstract: A multi-layered optical disc having superior recording/reproducing characteristics, in which the recording density in three-dimensional direction can be increased to increase the recording capacity, and its manufacturing method. A multi-layered optical disc 1 has a light reflecting layer 3, a second information recording layer 4, a transparent layer 5, a first information recording layer 6 and a light-transmitting layer 7 sequentially formed on a major surface 2a of its substrate 2. The laser light is illuminated from the light-transmitting layer 7 of the multi-layered optical disc 1 to record and/or reproduce information signals.

Abstract: A phase-change optical disc has a recording layer formed from a phase-change material switchable between a crystalline state and an amorphous state. The recording layer is illuminated signal-wise by a light is focused onto the recording layer to change the phase thereof from crystalline to amorphous, to thereby write an information signal onto the recording layer. The phase-change material contains a GeSbTe alloy. The recording layer is formed by sputtering in an Ar gas atmosphere containing at least either N2 or O2 gas or both. The optical recording medium exhibits improved durability after repeated recording and maintains a stable and good write/read characteristic even after repeated cycles of signal recording.

Abstract: A phase-changing optical disk solving the problem of difference in recording sensitivity between the land and groove without complexing configuration of the recording device or optical disk production scheme. The present invention provides a phase-changing optical disk including a substrate 11, provided with guiding grooves 17 to form the lands and grooves as the recording tracks, which are laminated with a first dielectric layer 12, second dielectric layer 13, recording layer 14, third dielectric layer 15 and reflection layer 16 in this order, wherein the material for the first dielectric layer 12 has a higher thermal conductivity than that for the second dielectric layer 13, and thickness of the second dielectric layer 13 is smaller than depth ds of the guiding groove 17.

Abstract: A recording medium comprising a hydrophilic film formed on a substrate, recording domains formed directly on the hydrophilic film so as to form a predetermined pattern, each recording domain being made of an organic dye molecule and having a size of 50 nm or less, and an isolation region surrounding the recording domains, the isolation region being made of an organic molecular film.

Abstract: An optical recording medium having sufficient repetition recording durability and its manufacturing method. A first dielectric layer 2 is layered on a major surface 1a of a substrate 1, and a recording layer 5, made up of two layers, namely a first thin film 3 and a second thin film 4 having different crystallization start temperatures, is formed on the first dielectric layer 2. A second dielectric layer 6, a reflective layer 7 and a protective layer 8 are then sequentially formed. One of the first thin film 3 or the second thin film 4 preferably contains nitrogen or oxygen. It is more desirable that the first thin film 3 lying towards the substrate 1 contains nitrogen or oxygen. The difference between the crystallization start temperature of the first thin film 3 and that of the second thin film 4 be 20° C. or more. It is more desirable that the crystallization start temperature of the first thin film 3 lying towards the substrate 1 be higher by 20° C. or more than that of the second thin film 4.

Abstract: A rewritable single-sided double layer optical information medium having a first recording stack with a phase change recording layer sandwiched between two dielectric layers. The recording stack is sufficiently transmissive to ensure proper reading/writing of the second recording stack. For this purpose, the recording stack includes a thin metal layer and a further dielectric layer. The laser beam can be focused on the first recording stack or on the second recording stack, thus doubling the storage capacity of the recording medium.

Abstract: An optical disk comprising a recording layer and a super-resolution film disposed on the reproduction-beam incident side of the recording layer, wherein the super-resolution film is formed of a fine particle-dispersed film comprising a matrix and semiconductor fine particles dispersed in the matrix or formed of a semiconductor continuous film, and wherein content of a matrix material or a contamination mixed in the semiconductor fine particles or the semiconductor continuous film is not more than 20 at %.

Abstract: Disclosed is an apparatus for formation of high quality plastic sheet in a continuous fashion. Also disclosed are a variety of optical and electronic display applications for high quality plastic sheet produced in a continuous fashion.

Abstract: An optical information recording medium comprising a substrate, a recording layer, a protective layer containing a sulfur atom, an intermediate layer in contact with the protective layer and a reflective layer containing silver as the main component in contact with the intermediate layer, wherein the intermediate layer comprises an element which does not form a compound with silver, the element contained in the intermediate layer having a solid solubility of at most 5 atomic % to silver and silver having a solid solubility of at most 5 atomic % to the element contained in the intermediate layer, on the side in contact with the reflective layer, and the intermediate layer comprises an element less reactive to sulfur or its sulfide comprises chemically stable elements, on the side in contact with the protective layer.

Abstract: An optical information recording medium includes a first dielectric protective layer, a recording layer provided on the first dielectric protective layer, including a material represented by a chemical formula of Ag&agr;In&bgr;Sb&ggr;Te&dgr;, wherein &agr;, &bgr;, &ggr; and &dgr; respectively represent an atomic percent of Ag, an atomic percent of In, an atomic percent of Sb, and an atomic percent of Te, and satisfy the conditions of: 1≦&agr;<10, 1<&bgr;≦20, 35≦&ggr;≦70, 20≦&dgr;≦35, &agr;+&bgr;+&ggr;+&dgr;=100, 4&bgr;−&dgr;≦0, &ggr;−2&dgr;≧0, and &ggr;−8&agr;≧0, a second dielectric protective layer provided on the recording layer, and a light reflection and heat dissipation layer provided on the second dielectric protective layer.

Abstract: There is disclosed a recordable optical element that has a substrate and on the surface of the substrate, a recording layer and a light reflecting layer. The recording layer has a material with the formula TeaGebCcHdOe wherein a, b, c, d, and e are atomic percents and (c+d)>40, d>10, a>5, b>5, and e≧0 such that a+b+c+d+e=100; and the reflecting layer and the recording layer being selected such that the element Rmax or Rmin (element reflectivity) is about or greater than 70% at about 780 nm.