Abstract: A silver-based alloy thin film is provided for the semi-reflective coating layer of optical discs. Alloy additions to silver include copper and a rare earth metal. These alloys have moderate to high reflectivity and reasonable corrosion resistance in the ambient environment.

Abstract: The present invention discloses an apparatus for indicating the passage of time, comprising a substrate and an indicating layer formed on the substrate. The indicating layer comprises a polymer matrix and a predetermined amount of redox compound under the reduced form. The redox compound is dispersed in the polymer matrix and has the following properties: the reduced form of the redox compound reacts with oxygen to form the oxidized form of the redox compound; the hue or color density of the reduced form of the redox compound is different from that of the oxidized form of the redox compound; and the hue or color density of the indicating layer varies as the time for the reduced form of the redox compound contacting with oxygen in environment increases to have the amount of the oxidized form of the redox compound increase so as to indicate the passage of time.

Abstract: A multi-layered phase-change optical recording medium having a first substrate and a second substrate, and a plurality of information layers, wherein each of thermal diffusion layers of information layers other than an information layer disposed at the innermost side as viewed from the first substrate side has In oxide, Zn oxide, Sn oxide and Si oxide, and when the contents of thereof are represented by “a”, “b”, “c” and “d” [mol %] respectively, the following requirements are satisfied, and when the refractive index of the first and second substrates was represented by “n”, the laser light wavelength is represented by “?” and the depth of the groove guide of the first and second substrates is represented by H, the H satisfied the following requirement, 3?a?50 0?d?30 a+b+c+d=100 ?/17n?H??/11.5n.

Abstract: [Problem]: An optical recording medium having a capability of recording and/or reading high density optical information using a short wavelength laser light is provided. [Means to Address the Problem]: The optical recording medium has a capability of recording and/or reading high density optical information using a short wavelength laser light having a wavelength of 350 nm to 530 nm. The optical recording medium has a recording layer containing a metal complex compound and formed on a substrate. The metal complex compound is composed of a cyclic ?-diketone azo compound represented by the general formula (I) or general formula (II) and a divalent metal ion coordinated to the cyclic ?-diketone azo compound.

Abstract: An information recording medium, 15 capable of recording information by irradiation of light or applying electrical energy, wherein at least one of first and second dielectric layers 102, 106, first interface layer and counter-incident side interface layer 103, 105 is formed from a Si—In—Zr/Hf—O-based material containing at least Si, In, M1 (M1 represents at least one element selected from among Zr and Hf) and oxygen (O), with Si content being 1 atomic % or more. This medium has high recording sensitivity when information is recorded thereon, high overwrite cycle-ability and high signal intensity.

Abstract: To provide an optical recording medium exhibiting favorable write/read characteristics in high-speed recording. In an optical recording medium including a reflective layer, a dye-containing recording layer, and a transparent resin layer on a substrate in this order, a barrier layer is disposed between the recording layer and the resin layer, where the barrier layer comprises a material having a bulk thermal conductivity M of 70 W/m·K or more at 300 K and has a thickness t less than 5 nm.

Abstract: An optical recording medium is an optical recording medium having an inorganic recording film and has a transparent conductive film on the inorganic recording film. The inorganic recording film has a first recording film containing titanium (Ti) and a second recording film containing an oxide of germanium (Ge). The transparent conductive film is provided on the side of the second recording film. The transparent conductive film contains an oxide of tin (Sn).

Abstract: An optical recording medium having excellent light resistance that includes a substrate; and a recording layer which is provided on the substrate directly or on another layer provided on the substrate, wherein the recording layer is capable of recording and/or reading information by irradiating light thereon, the recording layer includes a metal complex compound with an azo compound having a coupler component with indandione and a diazo component with a nitrogen-containing heterocyclic aromatic ring structure, and a nickel or cobalt ion coordinated to the azo compound.

Abstract: An optical recording medium having first protective layer, recording layer, second protective layer, and reflective layer, wherein the recording layer contains a phase-change material represented by Formula (1?1), Formula (1-2), or Formula (1-3); the second protective layer contains one selected from zinc oxides, indium oxides, tin oxides, mixtures thereof, and materials Formula (2), and materials Formula (3). Formula (1?1): In?iSb?iX1?i(X1: Ge, Te, Zn, Mn, or mixture thereof, 0.10??1?0.25, 0.65??1?0.80, and 0.04??1?0.15) Formula (1-2): Ga?2Sb?2SnY2Ges2X2?2 (X2: Te, Zn, Mn, In, or mixture thereof, 0.04??2?0.09, 0.56?62?0.79, 0.05??2<0.30, 0.03??2?0.19, and 0??2?0.09) Formula (1-3): Mn?3Sb?3SnY3Ge?3X3?3 (X3: Te, In, Zn, Bi, or mixture thereof, 0.04??3?0.09, 0.56?63?0.79, 0.05??3?0.29, 0.03??3?0.23, and 0??3?0.09) Formula (2): ZnO—Al—Y [(100??4?64):?4:?4] (Y: Mn, Ge, Ti, or mixture thereof, 0.5??4?10.0, and 0?B4?25.

Abstract: This invention relates to an optical recording medium in which at least a recording layer and a light transmitting layer are sequentially formed on a substrate and in which the light is illuminated from the light transmitting layer side for recording and/or reproducing information signals, said substrate comprising an injection molded part, and said substrate having a Young's modulus E of at least 2.15 GPa and a Q factor of lower than 160 measured at 25° C. at 2000 Hz in accordance to ASTM E 756-05 05 and a transcriptability of the pit/groove structure of >85%.

Abstract: The present invention provides an optical recording medium realizing reduced manufacturing cost of the optical recording medium. An optical recording medium 10 includes: a substrate 1; a recording layer 2 formed on the substrate 1, containing In, Sn, Pd, and oxygen, and containing oxygen atoms more than stoichiometric composition of the case where the In and the Sn are completely oxidized; and a light transmission layer 3 formed on the recording layer 2.

Abstract: The present invention provides a multi-layered object having a hard coat layer capable of improving anti-staining property, anti-staining durability, scratch resistance, abrasion resistance and the like. A multi-layered object comprising a hard coat layer and a light transmitting layer, wherein the hard coat layer is formed from a composition for hard coat comprising: an active energy ray-curable silicone-acrylic copolymer (A); and an active energy ray-curable polyfunctional compound (B), and wherein the active energy ray-curable silicone-acrylic copolymer (A) contains: a polysiloxane block (a-1), an acrylic block (a-2) containing an active energy ray-curable double bond group and a fluoroalkyl group-containing acrylic block (a-3).

Abstract: A method for rating an information recording medium according to the present invention includes the steps of: receiving a digital read signal, which has been generated based on an analog read signal representing information that has been read from the information recording medium, and shaping the waveform of the digital read signal; subjecting the shaped digital read signal to maximum likelihood decoding, thereby generating a binarized signal showing a result of the maximum likelihood decoding; and calculating the quality of the digital read signal based on the shaped digital read signal and the binarized signal. If the quality of the read signal is calculated by a PRML method in which a number of zero-cross portions are included in a merging path of a minimum difference metric, the quality is calculated by using only a state transition pattern in which only one zero-cross portion is included in a merging path of a non-minimum difference metric.

Abstract: The optical storage medium according to the invention uses a mask layer as a super resolution near field structure, which comprises a doped semiconductor material. The semiconductor material is n-doped particularly such that the reflectivity of the semiconductor material is increased, when irradiated with a laser beam. As a semiconductor material advantageously an indium alloy and as a doping material selenium or tellurium can be used. For the manufacturing of a respective optical storage medium a sputtering method for depositing the doped semiconductor material as the mask layer can be used, wherein the dopant is included already in the semiconductor sputtering target.

Abstract: There are provided a fine structural body capable of manifesting an unprecedented property; a manufacturing method thereof; and a magnetic memory, a charge storage memory and an optical information recording medium employing such fine structural body. Unlike conventional bulk bodies phase-transited between nonmagnetic semiconductors and paramagnetic metals around about 460K, there can be provided a fine structural body 1 comprised of Ti3O5, but capable of manifesting an unprecedented property in which a paramagnetic metal property thereof is consistently maintained in all temperature ranges without undergoing phase transition to a nonmagnetic semiconductor.

Abstract: An optical recording medium having a good power margin property during recording and good jitter during reading is provided. In an optical recording medium, a Ti recording layer that includes Ti as a main component and Al as an addition component and a first Si recording layer that is arranged adjacent to a cover layer side of the Ti recording layer and includes Si as a main component are stacked between a substrate and the cover layer.

Abstract: A system for altering a functionality of an optical article from a pre-activated state to an activated state, comprising an optical article comprising an optical data layer for storing data, an external radiation source for generating an external stimulus adapted to interact with the optical article, such interaction causing a change in optical accessibility of optically stored data, a directing material, wherein said directing material is for directing the external stimulus to selective portions of the optical article, thereby altering the functionality of the optical article from a pre-activated state to an activated state; a convertible element capable of responding to the external stimulus to irreversibly alter the optical article from the pre-activated state of functionality to the activated state of functionality, wherein said convertible element comprises a color-shift dye, a magnetic material, a thermo-chromic material, a magneto-optical material, a light scattering material, a phase-change material,

Abstract: The present invention relates to a data storage device comprising: a data storage medium for storing data in the form of topographic features; and at least one probe for writing and/or reading the data stored in the data storage medium, wherein the data storage medium is formed on a support layer, the support layer having a lower shear modulus than the data storage medium.

Abstract: An optical information recording medium includes a recording layer, wherein the recording layer includes a thermoplastic resin and inorganic oxide particles dispersed in the thermoplastic resin.

Abstract: An electrically responsive ink composition comprising at least one electrically responsive optical-state change material, at least one electrolyte material, at least one solvent, and at least one binder material, wherein the ink composition has a viscosity between about 0.1 centipoise and about 10,000 centipoise, and a maximum optical absorbance in a range from about 200 nanometers to about 800 nanometers; and wherein the ink composition is capable of transforming from a first optical state to a second optical state upon exposure to an electrical stimulus. The electrically responsive ink composition may be used to deposit an electrically responsive coating composition, which may be used as part of an anti-theft system for optical articles. Articles comprising electrically responsive coating compositions are also disclosed, as are methods for activation.

Abstract: A two-layered optical recording medium which includes a first substrate, a first information layer, a second information layer, and a second substrate formed in this order as viewed from the light beam irradiation side, the first information layer includes a first lower dielectric layer, a first recording layer, a first upper dielectric layer, a first reflective layer, and an inorganic dielectric layer formed in this order as viewed from the light beam irradiation side; the second information layer includes a second lower dielectric layer, a second recording layer, a second upper dielectric layer, and a second reflective layer formed in this order as viewed from the light beam irradiation side; and the first reflective layer is made of Cu with a content of 99.8% by mass to 95.0% by mass and one or more metals selected from Ta, Nb, Zr, Ni, Cr, Ge, Au, and Mo.

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 recording media includes a substrate, a cap layer opposite to the substrate, at least one first stacked recording structure, at least one second stacked recording structure, and a space layer. The first stacked recording structure including a first recording layer disposed between the substrate and the cap layer and a reflective layer disposed between the substrate and the first recording layer is disposed between the substrate and the cap layer. The second stacked recording structure including a second recording layer disposed between the substrate and the cap layer and an Nb2O5 interface layer disposed between the substrate and the second recording layer is disposed between the substrate and the cap layer. The spacer layer is disposed between the first and second stacked recording structures, the first stacked recording structures, and the second stacked recording structures. One of the first stacked recording structures is disposed directly on the substrate.

Abstract: An optical recording medium having a good power margin during recording is provided. In an optical recording medium, a Cu recording layer that includes Cu as a main component, a first Si recording layer that is arranged adjacent to the cover layer side of the Cu recording layer and includes Si as a main component, and a second Si recording layer that is arranged adjacent to the substrate side of the Cu recording layer and includes Si as a main component, are stacked between the substrate and the cover layer.

Abstract: An optical information recording medium has a substrate, and an optical reflection layer, an optical recording layer containing an organic dye, an interlayer, and a cover layer formed in this order on the substrate. The interlayer contains a sputtered Nb2O5—Al2O3-based composite oxide having an Nb2O5 content of more than 50 mol % and less than 60 mol %.

Abstract: A method for manufacturing an information recording medium including N information layers, (N?1) intermediate layers interposed between the information layers and a protective layer laminated on the Nth information layer placed on a substrate formed with a first reference point, including: forming the information layer on the substrate; repeating (N?1) times a process of applying radiation curable resin on the information layer, a process of affixing a transfer stamper formed with a second reference point to the radiation curable resin, a process of curing the radiation curable resin by irradiation, and a process of forming the intermediate layer by peeling the transfer stamper at an interface with the radiation curable resin, in order to form the (N?1) information layers and the (N?1) intermediate layers and thereafter form the Nth information layer; and forming the protective layer on the Nth information layer, wherein in the process of affixing the transfer stamper to the radiation curable resin, the trans

Abstract: A data storage master disk and method of making a data storage master disk. The data storage disk master is for use in a data storage disk replication process. The data storage disk molding processes produces replica disks having a surface relief pattern with replica lands and replica grooves. The method includes providing a master substrate. The master substrate is at least partially covered with a layer of photosensitive material. A surface relief pattern having master lands and master grooves is recorded in the data storage disk master, including the steps of exposing and developing the photosensitive material is controlled to form master grooves extending down to a substrate interface between the master substrate and the layer of photosensitive material, such that the width of the master grooves at the substrate interface corresponds to a desired width of the replica lands.

Abstract: To provide an optical recording medium in which error-causing short marks are produced in numbers small enough excellent high-recording characteristics and in which amorphous marks are uniform in shape. The optical recording medium includes: a first protective layer; a recording layer containing Sb as a main ingredient; a second protective layer; and a reflective layer, the first protective layer, the recording layer, the second protective layer and the reflective layer being provided in the order in which light passes through the medium for recording and reproduction of information, wherein the first protective layer and/or the second protective layer, both of which are in contact with the recording layer, are/is formed of a crystalline oxide.

Abstract: A composition, etc. are provided, which can enhance hardness and afford abrasion resistance even in a thin film as well as excellent antifouling property and durability of the antifouling property. An organic polymer, is provided, which comprises 5 to 30 weight percent of a radical polymerizable monomer having a perfluoroalkyl group, 0.01 to 5 weight percent of ?,?-dimercaptopolysiloxane, 5 to 40 weight percent of a radical polymerizable monomer having a cationic photo polymerizable epoxy group, and 25 to 75 weight percent of the other radical polymerizable monomer copolymerizable therewith, said organic polymer having a structure corresponding to a radical polymerizable copolymer of a mixture of the monomers in which a molar ratio of the mercapto group to the epoxy group is 0.0001 to 0.025, and/or a structure obtained by reacting the epoxy groups of the radical polymerizable copolymer with (meth) acrylic acid.

Abstract: An information recording medium of the present invention includes a recording layer whose phase changes by irradiation with a laser beam or application of current. The recording layer contains, as its main component, a composite composed of Ge and Sb that are essential components, and Te that is an optional component. The composite has a composition within a region enclosed by: point (a) (35, 65, 0), point (b) (36.9, 60, 3.1), point (c) (3.2, 60, 36.8), and point (d) (5, 95, 0) in terms of a coordinate (Ge, Sb, Te)=(x, y, z) on the triangular coordinate shown in FIG. 1, where point (b) corresponds to a point at Sb=60 on Ge60Te40—Ge35Sb65, point (c) corresponds to a point at Sb=60 on Te—Ge5Sb95, and the region includes lines extending between point (a) and point (b), point (b) and point (c), point (c) and point (d), and point (d) and point (a).

Abstract: A multi-layer information recording medium comprising a substrate that has an inner circumference and an outer circumference, three or more information recording layers and resin layers disposed between the information recording layers, wherein positions of the ends on the inner circumference side of the resin layers are different from each other in at least one combination of two neighboring resin layers, and the end on the inner circumference side of at least one of the resin layers is covered by another resin layer.

Abstract: A recording layer for an optical information recording medium, which has a high reflectance (initial reflectance) and excellent recording characteristics; an optical information recording medium comprising the recording layer; and a sputtering target useful for forming the recording layer. The recording layer for an optical information recording medium, on which recording is performed by irradiation of laser light, is characterized by containing indium (In) oxide and palladium (Pd) oxide which includes palladium monoxide and palladium dioxide. The recording layer for an optical information recording medium is also characterized in that the ratio of Pd atoms contained in the recording layer relative to the total of In atoms and Pd atoms contained therein is 6-60 atom %.

Abstract: An optical information recording medium having the same recording volume as that of DVD-ROM is obtained which shows excellent characteristics at recording linear velocities within a range of twice linear velocity of DVD (about 8.2 m/s) to five times liner velocity of DVD (about 20.5 m/s) and excellent archival stability, by a construction including a transparent substrate, a recording layer which is formed on the substrate directly or with another layer interposed therebetween and can change in phase reversibly by a laser beam irradiation, wherein the composition of the recording layer is within a region bounded by composition points A(41.2, 7.4, 51.4), B(39.8, 10.5, 49.7), C(28.5, 21.7, 9.8), and D(30.6, 15.8, 53.6) in a triangular coordinate graph represented with a coordinate of (Ge, Sb—Bi, Te) and a Bi content in the recording layer is 4 atom % and more and less than 13 atom %.

Abstract: An optical information recording medium includes a substrate having a through-hole provided at the central portion thereof and a guiding groove provided on a surface at the light-incident side; a reflective layer provided on the surface of the substrate having the guiding groove; a recording layer provided on the reflective layer and made of an organic substance containing a dye; and a light-transmissive cover layer provided on the recording layer, wherein the cover layer is made of a curable resin, and a modulus of elasticity of at least a portion of the cover layer facing the recording layer is in the range of about 34 MPa to about 96 MPa at 25° C.

Abstract: An optical disc (10) includes a substrate (11), which is formed from either a resin-impregnated paper produced by impregnating a paper with a resin, or a resin-coated paper produced by coating a surface of a paper with a resin, and a recording layer (13), wherein the resin contains at least one resin selected from the group consisting of polycarbonates, bisphenol A epoxy resins, copolymers of methyl methacrylate and styrene, and copolymers of acrylonitrile and styrene. Furthermore, a method of manufacturing an optical disc (20) includes: providing a recording layer sheet by forming tracks on a recording base material; and bonding the recording layer sheet to a resin-impregnated paper or a resin-coated paper, thereby providing a recording layer (13) formed from the recording layer sheet on the substrate (11).

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: An optical information recording medium that can simultaneously achieve both a high transmittance and high signal quality of an information layer, improve the reliability of long-term conservation, and reduce the manufacturing cost, and a manufacturing method thereof are provided. In an optical information recording medium including at least one information layer on a substrate, at least one of the information layers has a recording layer and a dielectric layer, the recording layer contains Te, O, and M (M is one or a plurality of elements selected from Au, Pd, and Pt) as major components, the dielectric layer has a thermal conductivity of 0.01 W/K·cm or more, and the dielectric layer has an extinction coefficient of 0 through 1.0 inclusive.

Abstract: A multilayer optical recording medium in which, as a recording layer is located farther from a surface of incidence of a light beam for reading, the amount of light that reaches the surface of incidence after being reflected off the recording layer is smaller.

Abstract: An optical medium including a plurality of data layers stacked relative to each other in a dielectric medium. A respective data layer including mark and land regions for having information recorded thereon. A mark region and a land region in the respective data layer are disposed beside each other and have substantially the same optical path length across respective thicknesses of the mark region and the land region. A method and computer program product associated with forming the optical medium which determines whether an admittance curve for a material to be used as the mark region forms an intersection with a desired admittance curve based on the admittance of a land region disposed beside the mark region, and determines a thickness of the material based on the intersection.

Abstract: The information recording medium of the present invention is provided with a substrate and an information layer including a recording layer. Rerecording and reproducing of information are performed by irradiating the information layer with a laser beam. The recording layer contains, as its main component, a material composed of Te, O, and M, where M denotes at least one element selected from Ru, Rh, Pd, Ag, Re, Os, Ir, Pt, and Au. In the material, the content of Te atom is 1 to 19 atom %, the content of O atom is 20 to 70 atom % (preferably 40 to 70 atom %), the content of M atom is 11 to 79 atom % (preferably 11 to 59 atom %, and more preferably more than 35 atom %). The material is, for example, is indicated as the region enclosed by A, B, C, and D, preferably by C, D, E, and F, and more preferably by E, F, H, and G, in the composition diagram of a ternary material of Te—O—Pd shown in FIG. 1.

Abstract: Optical recording mediums comprising a substrate and a recording layer and a light transmitting layer sequentially disposed on the substrate; wherein the substrate comprises one or more parts selected from the group consisting of injection molded parts, injection molded sandwich structures having a molded surface layer and a molded core layer or two injection molded parts which are UV-bonded, and combinations thereof; and wherein the substrate has a Young's modulus E of at least 2.15 GPa and a Q factor of lower than 160 measured at 25° C. at 2000 Hz in accordance to ASTM E 756-05.

Abstract: An information recording medium of the present invention includes recording layers 19 and 26 whose phase can change by an optical or an electrical system so as to be detectable, and interface layers 18, 20, 25 and 27, which are in contact with the recording layers 19 and 26, to serve as oxide layers. The recording layer 19 contains a Ge—Bi—Te-M material represented by a formula: Ge?Bi?Te?M100-?-?-? (atom %), where M denotes at least one element selected from Al, Ga, In and Mn, and ?, ? and ? satisfy 25???60, 0<??18, 35???55, and 82??+?+?<100. The interface layers 18, 20, 25 and 27 contain at least one oxide of the element M contained in the recording layers 19 and 26.

Abstract: An optical disc is described that bears, on one surface, a plurality of color-forming layers that can form a multicolored image when heated in contact with a thermal print head. The color-forming composition comprises color-forming layers and thermally-insulating spacers and is designed such that warping of the optical disc in conditions of changing temperature and humidity is minimized. The compliance of the color-forming composition is such that intimate contact between the thermal print head and the printable surface of the disc can be maintained as one is translated relative to the other. Methods for assembling such an optical disc are provided.

Abstract: The azo-metal chelate dye to which the present invention is applied is a compound formed as follows: for example, 1,3,4-thiadiazole ring is selected as the diazo component; the diazo component is combined with a coupler component having condensed rings including a fluorine-substituted alkylsulfonylamino group and an amino group, to form an azo dye compound; and the azo dye compound forms chelate bonds with at least one metal selected from the group consisting of Co, Ni, Cu and Pd. Here, two absorption bands (OD1 and OD2) are seen in the absorption spectrum, which is measured in a range of 400 to 800 nm wavelengths. The azo-metal chelate dye is characterized in that the optical density ratio (OD2/OD1) of the two absorption bands is greater than 1.25. By using this azo-metal chelate dye, an optical recording medium capable of high-speed recording is provided.

Abstract: The information recording medium (1) of the present invention includes a recording film (114, 124). The information recording medium (1) allows information to be recorded and reproduced on and from the information recording medium by irradiation of the recording film (114, 124) with a laser beam (18). The information recording medium (1) of the present invention further includes a mixed dielectric film (the second dielectric film 116, 126) disposed on the laser beam (18) incident side with respect to the recording film (114, 124). The mixed dielectric film contains a mixed dielectric material consisting of Zn sulfide, Si oxide and an oxide X (where the oxide X is an oxide of at least one element selected from Ti, Nb, Ta and Ce).

Abstract: In a write-once optical information recording medium including a substrate, a groove-shaped track such as a guiding groove, and an optical recording layer containing an organic dye material and disposed on the guiding groove, wherein information is recorded by irradiating a short-wavelength laser beam from a surface of the optical recording layer opposite the substrate, and the information can be reproduced by reading a change in the reflected light of a short-wavelength laser beam after the information recording, an unrecorded portion of the optical recording layer has a lower reflectance than a pit portion formed after recording to a portion of the optical recording layer, the optical recording layer has a refractive index n in the range of about 1.2 to about 2.1 before recording and an extinction coefficient k in the range of about 0.01 to about 0.7 before recording, and n+k is in the range of about 1.4 to about 2.1.

Abstract: The present invention provides a solid material comprising an immobilized mixture of two or more proteorhodopsins, two or more bacteriorhodopsins, or one or more bacteriorhodopsin and one or more proteorhodopsins. The proteorhodopsins are selected from the group consisting of all-trans-retinal-containing proteorhodopsins and retinal analog-containing proteorhodopsins; all of which have absorption spectra that do not overlap. The bacteriorhodopsins are selected from the group consisting of all-trans-retinal-containing bacteriorhodopsins and retinal analog-containing bacteriorhodopsins; all of which have absorption spectra that do not overlap. The present invention also provides an optical information carrier, such as an optical data storage material and a fraud-proof optical data carrier, comprising the above-described solid material and a substrate selected from the group consisting of glass, paper, metal, fabric material, and plastic material, wherein said solid material is deposited on said substrate.

Abstract: A method for producing optical discs is provided. A substrate for an optical disc is formed by utilizing a molding process. A textured surface is formed at an outer diameter edge of the substrate. A protective coating is applied to cover the textured surface at the outer diameter edge. The protective coating adheres securely to the textured surface at the outer diameter edge to prevent seepage of moisture into the optical disc through the outer diameter edge surface. Thus, an improved optical disc which avoids moisture-caused warpage, corrosion and/or oxidation can be formed.

Abstract: An object of the invention is to improve the quality of a servo signal and a reproduction signal. Shape-wise thicknesses tr1, tr2, . . . , and trN of a cover layer and first through (N?1)-th intermediate layers of an optical recording medium having refractive indexes nr1, nr2, . . . , and nrN are converted into thicknesses t1, t2, . . . , and tN of the respective layers having a predetermined refractive index “no” which makes a divergent amount equal to a divergent amount of a light beam resulting from the thicknesses tr1, tr2, . . . , and trN, a difference DFF between the sum of a thickness “ti” through a thickness “tj”, and the sum of a thickness “tk” through a thickness “tm” is set to 1 ?m or more (where i, j, k, and m are each any positive integer satisfying i?j<k?m?N), and the thicknesses t1, t2, . . . , and tN are calculated by products of a function f(n) expressed by the following formula (1), and the thicknesses tr1, tr2, . . . , and trN: f(n)=?1.088n3+6.1027n2?12.042n+9.

Abstract: An optical recording medium including a substrate, an information recording layer including a recording layer and a cover layer, wherein information is written and read on the information recording layer by irradiation of laser beam via the cover layer, the cover layer includes an ultraviolet curing resin and an inner hardness Hi defined as hardness H of the cover layer on a side of the information recording layer satisfies the following relationship: 3.8?Hi?5.5, when H=3.8584×F/(h×h), wherein h represents an indented depth in a state in which a triangular pyramid indenter with a tip angle of 115° is pressed under F=9.8 mN.