Abstract: The present invention provides an optical information recording medium including a substrate having successively disposed thereon a light-reflective layer, a recording layer and a cover layer, wherein information can be recorded on and reproduced from the recording layer by irradiating a laser beam from a side at which the cover layer is disposed, and a surface of the light-reflective layer at a side at which the recording layer is disposed has a central surface average roughness SRa of 30 nm or smaller and a number of projections having a height from a reference plane of 50 nm or greater, as determined with an atomic force microscope (AFM), of 30 (number/90 &mgr;m angle) or less.

Abstract: The present invention relates to an optical memory device and an operating process thereof. The optical memory device have a recording layer containing a photochromic compound and an electron-accepting compound which is a Lewis acid compound having a Lewis acid part and a long chain part having carbon atoms of C12 or more. One aspect of the operating process has a recording step which recording is performed on the optical memory device by irradiating visible light corresponding to the absorption band of the colored photochromic compound for recording using decolorizing, before and after recording, heating treatments are performed to control the decolorizing sensitivity of the photochromic compound, and an erasing step which ultraviolet light is irradiated to the area including the recorded portion in order to uniformly color the recording layer again.

Abstract: Methods and apparatus are provided for making an optically readable media unreadable. The method includes steps of (a) providing the media with an optically activated mechanism that degrades the reflectivity of a surface wherein information is encoded; (b) exposing the media to optical radiation for reading out the information; and, during the step of exposing, (c) initiating the operation of the optically activated mechanism. In this embodiment the step of initiating includes steps of (d) generating singlet oxygen in a layer disposed on the media; and (e) reacting the singlet oxygen with a metal-containing layer for oxidizing the surface of the metal-containing layer, thereby degrading the reflectivity of the surface. In a further aspect the optically activated mechanism causes a defocusing of a readout beam, thereby degrading reflection of the readout beam from a surface wherein information is encoded.

Abstract: Noise of the read-out signal is reduced in an optical information medium comprising a supporting substrate and a reflective layer disposed on the supporting substrate wherein the reading beam irradiates the medium from the side where the reflective layer is formed. In addition, noise of the read-out signal is reduced without adversely affecting the recording properties in an optical information medium comprising a supporting substrate, and a reflective layer and a recording layer disposed on the supporting substrate in this order wherein the recording beam irradiates the medium from the side where the reflective layer is formed. In the medium, the reflective layer has a crystallite size of up to 30 nm.

Abstract: The present invention provides an oxidative coupling procedure that allows efficient synthesis of novel cyclo[n]pyrrole macrocycles. Therefore, the present invention provides cyclo[n]pyrroles where n is 6, 7, 8, 9, 10, 11, or 12, and derivatives, multimers, isomers, and ion and neutral molecule complexes thereof as new compositions of matter. A protonated form of cyclo[n]pyrrole displays a gap of up to 700 nm between strong Soret and Q-like absorption bands in the electronic spectrum, demonstrating no significant ground state absorption in the visible portion of the electronic spectrum. Uses of cyclo[n]pyrroles as separation media, nonlinear optical materials, information storage media and infrared filters are provided.

Abstract: An optical data storage medium containing a preferably transparent substrate which has optionally already been coated with one or more reflecting layers and onto the surface of which a photorecordable information layer, optionally one or more reflecting layers, and optionally a protective layer or an additional substrate or a top layer are applied, which data storage medium can be recorded on and read using blue or red light, preferably laser light, wherein the information layer contains a light-absorbing compound and optionally a binder, characterized in that at least one triazacyanine dye is used as the light-absorbing compound.

Abstract: An optical recording medium having a recording layer which contains at least one compound selected from the group consisting of mono-, di-, and triazaporphyrin compounds optionally in the form of a metal complex; or an optical recording medium comprising a substrate and formed thereon at least a recording layer containing an organic dye as a main component, characterized in that the organic dye has a first maximum value of absorption at a wavelength &lgr;1 of 400 nm or less in the absorption spectrum and has a second maximum value of absorption at a longer-wavelength side than the &lgr;1, and a wavelength band wherein the refractive index (n) and the absorption coefficient (k) of the above organic dye satisfy n≧1.90 and 0.03≦k≦0.30.

Abstract: An object of the present invention is to provide a material having spectroscopic properties, light resistance, solubility and thermal decomposition properties suitable for recording for DVD-R.

Abstract: An optical information recording medium including a substrate having successively disposed thereon a recording layer, an interlayer, a pressure sensitive adhesive layer and a cover film in which information is recordable and reproducible by irradiating laser light and the pressure sensitive adhesive layer contains a polymer having a glass transition temperature Tg of 0° C. or lower, as well as a method for producing an optical information recording medium including adhering a cover layer to a surface of a recording layer so that a pressure sensitive adhesive layer is abutted on the surface of the recording layer, and an optical information recording medium produced by the method.

Abstract: An optical information recording medium includes a substrate having disposed thereon a recording layer that is recordable by irradiating the recording layer with a laser having a wavelength of 450 nm or less. The recording layer contains a specific phthalocyanine derivative. An optical information recording method uses the medium.

Abstract: A donor element for use in laser thermal imaging has a layer which comprises an infrared-absorbing material, an image dye and a polymer matrix comprising a thermally degradable polymer and a non thermally degradable polymer there being an interaction between the infrared-absorbing material and the non degradable polymer to facilitate retention of the infrared-absorbing material in the donor element. The degradable and non degradable polymers are preferably copolymers both of which contain methacrylic acid as a monomer. The degradable polymer is preferably a copolymer of methoxyethyl cyanoacrylate and methacrylic acid preferably in molar proportions of from 1:1 to 12:1. The non degradable polymer is preferably a copolymer of methyl methacrylate and methacrylic acid, preferably in molar proportions of from 1:1 to 15:1.

Abstract: This invention is a method comprising preparing a sample by coating a thin film of a precursor material, which is free of fluorescent probe molecules onto a substrate and subjecting the precursor material to conditions to attempt to cause cure of the precursor to an organic, aromatic, polymer having a dielectric constant of less than 3.0, exposing the sample to radiation having a wavelength in the range of 200 to 500 nm, detecting a resulting emission of radiation, and comparing the emission to the emission for a known cured, non-oxidized standard for the polymer.

Abstract: The present invention is an optical information recording medium comprising a substrate having disposed in an order thereon a recording layer, an interlayer, and a cover layer, wherein recording and reproduction are carried out by the irradiation with a laser light having a wavelength in the range of 380 to 500 nm through a lens having a lens numerical aperture NA of 0.7 or more, wherein the recording layer is a layer of an organic substance and the thickness of the interlayer is within a range of 1 nm to 9 nm.

Abstract: Disclosed is an optical information recording medium comprising a substrate having provided thereon a recording layer capable of recording information by laser beam irradiation, wherein the recording layer contains at least one compound represented by the following general formula (I): 1

Abstract: Disclosed is an optical recording medium comprising a recording layer. The recording layer contains: a charge generation material generating an electron and a hole by light irradiation; a charge transport material transporting one of the electron and the hole; a charge trap which traps the transported one of the electron and the hole to separate the electron and the hole; and a non-linear optical material which changes optical properties of the recording layer in accordance with electric field formed by the electron and the hole being separated from each other. The non-linear optical material has an asymmetrical carbon atom and a cyclic group. Or, it is a cyclic-group-containing constituent having: an inversion symmetric pi-electron system; at least one of an electron donating group and an electron accepting group which are bonded to the inversion symmetric &pgr;-electron system; and an asymmetrical carbon atom.

Abstract: An optical recording material which when exposed to actinic radiation produces a change in optical properties in the exposed regions, thereby providing a pattern of intelligence for storing and retrieving information, the recording material comprising: a) a binder; b) a reactant which is capable of undergoing a chemical transformation upon a one electron oxidation, thus causing the change in optical properties in the exposed regions; and c) a sensitizer capable of absorbing actinic radiation to cause an initial one electron oxidation of the reactant.

Abstract: Optical data carrier comprising a preferably transparent substrate which may, if desired, have previously been coated with one or more reflection layers and to whose surface a light-writeable information layer, if desired one or more reflection layers and, if desired, a protective layer or a further substrate or a covering layer have been applied, which can be written on or read by means of blue or red light, preferably laser light, where the information layer comprises a light-absorbent compound and, if desired, a binder, characterized in that at least one xanthene dye which contains at least two anionic groups and has at least one cation containing at least one conjugated &pgr; system having at least 6 &pgr; electrons as counterion, where the cation must not be benzyltrimethylammonium, benzyltriethylammonium, tetraphenylphosphonium, butyltriphenylphosphonium or ethyltriphenylphosphonium, is used as light-absorbent compound.

Abstract: An optical recording medium having an organic dye layer as a recording layer on a substrate, wherein at least one benzobisazole-based compound represented by a general formula (1) is contained in the recording layer: 1

Abstract: Dye precursor molecules—normally rhodamine base—held in a transparent matrix are reactive with acids, bases, ions or radicals—and in the case of rhodamine are reactive with acids—to produce dye molecules—i.e., rhodamine—having markedly different spectroscopic properties. Light-sensitive molecules—normally a compound of ortho-nitro-aldehyde, in particular o-nitro-benzaldehyde or, preferably, 1-nitro-2-naphthaldehyde—in the same matrix undergo photochemical reaction when selectively exposed to light so as to form at least one of the acids, bases, ions or radicals with which the dye precursor molecules are reactive—preferably nitroso acid.

Abstract: An optical disk includes a standard area of a standard recording density provided on an inner peripheral sided and a high density area of a higher recording density provided on an outer peripheral side. In each of the standard area and the high density area, a program area is provided so that an independent program can be recorded in each program area. In one aspect of the invention, an optical disk includes, from the inner preriphery to the outer periphery of the disk, a ROM area for read-only purpsoe, a RAM area in which information can be rewritten and a WO area in which information can be written only once.

Abstract: An optical data storage medium containing a preferably transparent substrate which has optionally already been coated with one or more reflecting layers and onto the surface of which a photorecordable information layer, optionally one or more reflecting layers, and optionally a protective layer or an additional substrate or a top layer are applied, which data storage medium can be recorded on and read using blue or red light, preferably laser light, wherein the information layer contains a light-absorbing compound and optionally a binder, characterized in that at least one hemicyanine dye is used as the light-absorbing compound.

Abstract: An optical information recording disc showing good recording characteristics is prepared by the steps of coating a dye solution of a laser light-sensitive dye in a fluorinated cyclic alkane or alkene on a transparent substrate disc and drying the coated dye solution. The fluorinated cyclic alkane or alkene can be employed in combination with other organic solvents.

Abstract: Methods and apparatus are provided for making an optically readable media unreadable and tamper-resistant. A method has steps of (a) providing the media with a readout surface layer that is non-flat (i.e., textured in some way, such as by embossing, scratching, depositing a non-planar layer or regions, such as droplets) and that inhibits optical readout of the media; (b) applying a coating layer to the non-flat surface layer to smooth the non-flat surface and to enable optical readout of the media; and, after an initiation of a readout period, (c) removing the coating layer so as to expose the non-flat readout surface layer, thereby inhibiting optical readout of the media. Preferably, the coating layer is substantially index matched to the readout surface layer.

Abstract: The present invention provides a rhodamine dye for recording layer of the high density optical recording disc, which has a chemical structure as shown in (I): 1

Abstract: The present invention provides an optical information recording medium that includes a substrate including a groove with a track pitch of 200 to 400 nm and a groove depth of 20 to 150 nm and having successively disposed thereon a light reflecting layer, a recording layer containing a dye in which information is recorded by irradiation with a laser beam having a wavelength of no greater than 450 nm, an adhesive layer, and a cover layer with a thickness of 0.01 to 0.5 mm. A surface of the optical information recording medium on a side disposed with the cover layer has a center surface average roughness (SRa1) of no greater than 3.0 nm when measured over a large surface area and a center surface average roughness (SRa2) of no greater than 3.0 nm when measured over a minute surface area.

Abstract: A three dimensional optical data storage and retrieval system that includes a three dimensional optical data storage medium and an apparatus for providing access to data stored on the medium. The data storage medium includes an optical data storage material which either a low molecular weight or polymeric glassy solid that are capable of undergoing multi-photon excitation that are energetically different in the write and read cycles. The optical data storage materials provide substantially higher storage capacities relative to conventional materials, and show high robustness in that written and stored data can undergo multiple read cycles without erasure or overwriting. An apparatus for data recording and accessing stored data on the medium includes a controllable variable energy photo-emitting excitation source and an emission photo-detector.

Abstract: The present invention is directed to styryl dyes having the formula: 1

Abstract: Optical data carrier comprising a preferably transparent substrate which may, if desired, have previously been coated with one or more reflection layers and to whose surface a light-writeable information layer, if desired one or more reflection layers and if desired a protective layer or a further substrate or a covering layer have been applied, which can be written on or read by means of blue, red or infrared light, preferably laser light, where the information layer comprises a light-absorbent compound and, if desired, a binder, characterized in that at least one cationic aminoheterocyclic dye is used as light-absorbent compound.

Abstract: Optical data carrier comprising a preferably transparent substrate which may, if desired, have previously been coated with one or more reflection layers and to whose surface a light-writeable information layer, if desired one or more reflection layers and if desired a protective layer or a further substrate or a covering layer have been applied, which can be written on or read by means of blue, red or infrared light, preferably laser light, where the information layer comprises a light-absorbent compound and, if desired, a binder, characterized in that at least one merocyanine dye is used as light-absorbent compound.

Abstract: The present invention relates to novel compounds of the naphthopyran type which have an annelated carbocycle in position 5,6.

Abstract: Optical data carrier comprising a preferably transparent substrate which may, if desired, have previously been coated with a protective layer and to whose surface a light-writable information layer, if desired a protective layer, if desired an adhesive layer and finally a covering layer have been applied, which can be written on and read by means of blue light, preferably laser light, where the information layer comprises a light-absorbent compound, characterized in that at least one dye which cyclizes thermally is used as light-absorbent compound.

Abstract: The present invention provides a fluorinated alcohol for manufacturing an optical recording medium that is superior in the characteristics and weatherability, and an optical recording medium having an organic dye layer formed by using the fluorinated alcohol. A fluorinated alcohol for manufacturing an optical recording medium having an organic dye layer and a reflecting layer in this order on a light-transmittable substrate, wherein a content of a high-boiling-point fluorinated alcohol with a boiling point of not less than 120° C. is 0.001% by weight or less. An optical recording medium is provided with an organic dye layer formed by using the ultra-high purity fluorinated alcohol.

Abstract: An optically readable media and packaging therefor, where the media includes a material that over time undergoes at least one of a chemical change or a physical change to render unreadable the optically readable media. The media is sealed within the packaging with a source of a chemical compound that inhibits the change, and the media is also sealed within the packaging with a getter of the chemical compound that over time absorbs said chemical compound, or which a substance that over time renders unreactive a reactive chemical compound. In a further embodiment the media is sealed within the packaging with a getter of a chemical compound that promotes the change. In this case the getter absorbs the chemical compound until saturated with the chemical compound, after which the concentration of the chemical compound increases until the media is rendered unreadable. As non-limiting examples, the chemical compound may be NMP, DMF, acetone, or HCl.

Abstract: In the optical information recording medium of the present invention, a first recording layer having a translucent film and a second recording layer having a reflection film are layered. At least one layer of the first recording layer is provided, and the translucent film reversibly varies its reflectance and its transmittance according to a temperature variation caused by difference in a converging state of reproducing light. This ensures to obtain a sufficient amount of the reproducing light reflected from the first and second recording layers.

Abstract: An apparatus for retrieving information stored on an optical disk as colored dots, using an array of laser diodes emitting multiple wavelengths. Colored dots store more information than pits and spaces on optical disks because each colored dot represents a multiple-bit code of information rather than a single bit. The optical disk reader directs multiple wavelength diode laser beams to the disk surface. The reflected beams are then separated using an array of dichroic filters, and sent to light sensors. The light sensors identify the intensity of each of the reflected frequencies and determine the wavelength combination being reflected from the optical disk, which corresponds to a multiple-bit code.

Abstract: Optical data carrier comprising a preferably transparent substrate which may, if desired, have previously been coated with a reflection layer and to whose surface a light-writeable information layer, if desired a reflection layer and if desired a protective layer or a further substrate or a covering layer have been applied, which can be written on or read by means of blue, red or infrared light, preferably laser light, where the information layer comprises a light-absorbent compound and, if desired, a binder, characterized in that the light-absorbent compound has at least two identical or different chromophoric centers and has at least one absorption maximum in the range from 340 to 820 nm.

Abstract: In a write once optical recording medium comprising a recording layer and a light transmitting protective layer formed successively on a supporting body, for recording and reproduction by irradiating a laser beam of a 380 to 450 nm wavelength from the light transmitting protective layer side, &lgr;max≦370 nm on the premise that the wavelength providing the peak optical absorption coefficient of the recording layer is defined to be &lgr;max.

Abstract: A secure, optically readable data medium comprises a data-carrying zone readable by a read light beam, and at least a portion that is photosensitive, being provided with a photosensitive material and exposed to the read light beam. The photosensitive material contains an active compound taken from the family of diarylethenes.

Abstract: This invention concerns a luminescent optical memory material and method of forming this material, including the encoding of information by a photographic process. The method involves the use of silver halide crystals of a defined size range, with the optional use of sensitizers, emulsion stabilizers, and other agents followed by the absorption of luminescent dyes on the developed silver particle to form a luminescent optical memory system. The method involves synthesis of a photographic emulsion with silver halide crystals of a defined size range, applying photographic emulsion to a substrate, exposing to light photochemical treatment and a process of transformation of the silver particles formed in the places exposed by light into luminescent particles. The method involves obtaining a multi-layer luminescent material for a three-dimensional optical memory devices.

Abstract: Dye precursor molecules—normally rhodamine base—held in a transparent matrix are reactive with acids, bases, ions or radicals—and in the case of rhodamine are reactive with acids—to produce dye molecules—i.e., rhodamine—having markedly different spectroscopic properties. Light-sensitive molecules-normally a compound of ortho-nitro-aldehyde, in particular o-nitro-benzaldehyde or, preferably, 1-nitro-2-naphthaldehyde—in the same matrix undergo photochemical reaction when selectively exposed to light so as to form at least one of the acids, bases, ions or radicals with which the dye precursor molecules are reactive—preferably nitroso acid.

Abstract: In a multilayer recordable optical medium, each recording layer includes a luminophore that fluoresces under reading laser light and a quencher capable of quenching the luminophore fluorescence. Initially, the luminophore and the quencher are not intermixed, so that the default state of the luminophore is fluorescent. During writing, focused writing radiation heats a spot in the medium so as to cause the luminophore and the quencher to be intermixed, thereby quenching the fluorescence.

Abstract: This invention provides azo-metal complex dyes for a high-density optical disc recording medium having the following formula (I): 1

Abstract: Methods and apparatus are provided for making an optically readable media unreadable. The method includes steps of (a) providing the media with an optically activated mechanism that degrades the reflectivity of a surface wherein information is encoded; (b) exposing the media to optical radiation for reading out the information; and, during the step of exposing, (c) initiating the operation of the optically activated mechanism. In this embodiment the step of initiating includes steps of (d) generating singlet oxygen in a layer disposed on the media; and (e) reacting the singlet oxygen with a metal-containing layer for oxidizing the surface of the metal-containing layer, thereby degrading the reflectivity of the surface. In a further aspect the optically activated mechanism causes a defocusing of a readout beam, thereby degrading reflection of the readout beam from a surface wherein information is encoded.

Abstract: An object of the invention is to provide a method for preparing an optical recording medium, featuring a high production yield, a reduced loss and a high utilization of dye solution, and ensuring to produce media of consistent quality even by continuous coating as well as an optical recording medium. The object is achieved by a method for preparing an optical recording medium, comprising the step of applying a solution of a dye in a solvent onto a resin substrate to form a dye film, wherein the solvent of the dye solution is a mixture of tetrafluoropropanol and/or octafluoropentanol with an aliphatic saturated alcohol of 1 to 4 carbon atoms, and a recording layer is formed by applying the dye solution.

Abstract: A near-field optical recording medium comprises a recording layer capable of writing, reading and erasing information using an evanescent light, the evanescent light having a beam spot size smaller than the wavelength of a source light, wherein the recording layer is a stable amorphous layer mainly comprising a photochromic compound having a glass transition point of 55° C. or higher and a molecular weight of 3000 or less.

Abstract: An organic or organoelement, linear or branched, monomeric or polymeric composition of matter having a Raman-active component in the form of particles. The particles having a maximum dimension of 50 &mgr;m. The Raman-active compound is applied to a substrate. When the Raman-active compound is exposed to a laser light wavelength which is batochromically well beyond a spectral region of maximum absorbance of said Raman-active compound, Raman scattering can be detected.

Abstract: An optical information recording medium comprising a light transmitting substrate, a light absorptive layer containing at least one light absorbing substance formed on the substrate and a light reflective layer made of a metal film formed on the light absorptive layer, wherein an optical parameter represented by &rgr;=nabsdabs/&lgr; wherein nabs is the real part of the complex refractive index of the light absorptive layer, dabs is the average thickness of the light absorptive layer and &lgr; is the wavelength of a reading laser beam, is 0.6<&rgr;<1.6.

Abstract: Methods and apparatus are provided for making an optically readable media unreadable. The method includes steps of (a) providing the media with an optically activated mechanism that degrades the reflectivity of a surface wherein information is encoded; (b) exposing the media to optical radiation for reading out the information; and, during the step of exposing, (c) initiating the operation of the optically activated mechanism. In this embodiment the step of initiating includes steps of (d) generating singlet oxygen in a layer disposed on the media; and (e) reacting the singlet oxygen with a metal-containing layer for oxidizing the surface of the metal-containing layer, thereby degrading the reflectivity of the surface. In a further aspect the optically activated mechanism causes a defocusing of a readout beam, thereby degrading reflection of the readout beam from a surface wherein information is encoded.

Abstract: A dye precursor represented by the following formula (I): wherein A1 and A2 each represents an atomic group to form a coupler residue together with —N(R5)R6 and the carbon atom to which A1 and A2 are bonded; R1 represents a substituent; n represents an integer of from 0 to 4; R2 represents a hydroxyl group or a group represented by —N(R7)R8; R7 and R8 each independently represents a hydrogen atom or a substituent; R3 and R4 each independently represents a hydrogen atom or an alkyl group; and R5 and R6 each independently represents a substituent.

Abstract: The invention includes a method of manufacturing a fluorescent 3-D optical memory device implementing an active medium capable of storing information at high information density, and an optical memory device manufactured by this method. The active medium employed in the present invention is a material capable of existing in at least 2 isomeric forms. Transition from one form to another can be induced upon illuminating this material by a “writing” electromagnetic radiation having a first spectrum. At the same time the other isomeric form is capable of fluorescence upon illuminating this material by a “reading” electromagnetic radiation with a second spectrum. By virtue of illuminating with a radiation having the first spectrum there are created elemental cells within a medium material, containing substantially the same isomeric form thereof, which can be either that form which is capable of fluorescence or the other one which is not.