Abstract: By forming recording layer (3), or recording material particles (10), (13) dispersed in protection material (9) with the laser sputtering, the initialization of recording layer (3) become, unnecessary or easy, and optical storage medium having long repetition life of recording and erasing is obtained.

Abstract: A composition of materials having ferromagnetic, piezoelectric, and electro-optical properties is disclosed. In the preferred embodiment, the composition of materials comprises a first layer of Pb.sub.(1-x-y) Cd.sub.x Si.sub.y, a second layer of Se.sub.(1-z) S.sub.z, and a third layer of Fe.sub.(1-w) Cr.sub.w, where x, y, z and w are values within the ranges of 0.09.ltoreq.x.ltoreq.0.11, 0.09.ltoreq.y.ltoreq.0.11, 0.09.ltoreq.x.ltoreq.0.11 and 0.18.ltoreq.w.ltoreq.0.30. Additionally, each of the layers contain at least one of the elements of Ag, Bi, O, and N. A random-accessible, non-volatile memory built using the invented composition of materials is also disclosed. This memory provides for storing two independent bits of binary information in a single memory cell.

Abstract: A recording medium includes a substrate electrode, a recording layer constituted of a monomolecular film of an organic compound or a built-up film thereof, and a photoconductive thin film, laminated in this order on a substrate. The photoconductive thin film may preferably be divided to a plurality of isolated sectors. The recording medium is used in an ultra high density information processing apparatus with a probe electrode disposed close to the medium, a power source for applying a voltage between the medium and the probe electrode, and a light source for irradiating the medium.

Abstract: This invention, related to an optical information recording medium for recording, reproducing and erasing information by causing changes in the optical constant by using light, heat or other means, is intended to propose a recording film material of a novel composition in order to realize higher transfer rate of signals. Specifically, it is an alloy composed of indium (In) and A and B (A is at least one element selected from Ag, Cu, and B is at least one element selected from S, Se, Te), and more particularly it is composed in the vicinity of the stoichiometric compound of the above three-element system.Since the recording film material of this invention is fast in the rate of crystallization, it is possible to present an optical information recording medium that can cope with the forthcoming trend of higher transfer rate of signals.

Abstract: An optical storage medium including a transparent polymer and an isomerizable AZO dye, the optical storage medium being coated as a water miscible solution on a substrate so as to form a film having a thickness of from .mu.m to 100 .mu.m storing information through birefringence and having a diffraction efficiency greater than 40% at a 1 millisecond response time. The isomerizable AZO dye remains in the film and is present in a concentration of from 4.5% to 25% based on the weight of the film.

Abstract: Disclosed herein is an optical recording medium comprising a recording layer containing a photochromic material and a polymer which are so combined with each other that a photostationary state attained upon irradiation with light of a specific wavelength is varied with temperatures, a reflective layer for reflecting light which is passed through the recording layer, and a substrate for supporting a laminate of the recording layer and the reflective layer.

Abstract: The present invention provides a photochromic material which comprises a spiropyran compound of formula (I): ##STR1## wherein R.sup.1 and R.sup.2 are independently alkyl groups each containing 1 to 30 carbon atoms and Y is a halogen.The photochromic material possesses absorption sensitivity at wavelengths in the length region of about 700 nm which is the oscillation range of a semi-conductor laser device, and possesses higher stability compared with conventional one when it becomes a colored form.

Abstract: A stable, image-retaining, optically switchable film produced from a purple membrane in a high-pH polyvinyl alcohol solution forms an optical memory for data storage. The film, when dry, can be exposed to light to convert BR molecules to their M state, which is stable, and which allows long-term image storage. The image can be erased by exposing the film to yellow light to thereby switch all the molecules to the M state, and then a reverse image can be obtained using blue light. By controlling the location and wavelength of the incident light, pixels can be selected and exposed for information storage.

Abstract: The optical data recording media is provided on a substrate with a recording layer changing its optical characteristic dependent upon difference in the heat history, or processes of temperature elevation due to laser beam irradiation and the following cooling. The media is composed of layered structure not only varying its own reflectance or transmittance as an integrated media, but also changing the optical phase of the reflected light or transmitted light, when the optical characteristic of the recording layer is changed. In the method of recording, erasing and reproducing data using this optical data recording media, when the variations of the reflectance is to be detected, recording and erasing are effected after temporarily setting the recording layer in a state having a higher reflectance. On the other hand, when the variations of the transmittance is to be detected, recording and erasing are effected after temporarily setting the recording layer in a state having a higher transmittance.

Abstract: A high dielectric polymeric optical recording medium for recording information by heating the portions of the recording medium corresponding to the information to be recorded by being exposed to a beam of light, followed by the application of a reverse electric field to the recording medium, thereby selectively reversing the polarity of the heated portions in the recording medium, is disclosed, which comprises a high dielectric polymeric recording layer containing a high dielectric polymeric composition comprising a high dielectric polymeric material and a nonionic dye serving as a light-absorption agent which is compatible with or dispersible in the high dielectric polymeric material.

Abstract: An optical recording structure comprises a thermally stable substrate and a polymeric layer deposited on the substrate comprised of a poly(ester-amide). Laser beams are directed at the deposited polymeric layer to record or erase information. The recording structure has an excellent dimensional and mechanical stability on storage, readily and easily records information, and has an ability to be easily and completely erased.

Abstract: An optical recording medium and a method of writing, reading and erasing information in an optical recording medium are provided in which the optical recording medium comprises a carrier and a recording layer which contains at least one optically active organic compound, wherein said optically active organic compound is an inherently chiral dissymmetric olefinic chromophore.

Abstract: Thiophene derivatives represented by the general formula (I): ##STR1## where R is an aldehyde, carboxyl, C.sub.1-5 -alkyl ester or C.sub.1-5 -alkyl acetal group and n is 3 to 5, are prepared. These compounds are reversibly converted to their respective isomers by light irradiation, accompanied with a large shift of absorption and emission bands, thus suitable for a photo-responsive material.

Abstract: A process for the reversible or irreversible production of an image by imagewise exposure of a recording layer to energy in the presence or absence of an electrical and/or magnetic field, resulting in a pattern of surface charges on the surface of the recording layer corresponding to the imagewise exposure to energy. The recording layer consists essentially ofan organic material which solidifies in a glass-like manner, is non-photoconductive or substantially non-photoconductive and contains permanent dipoles, in whichthe pattern of surface charges is produced without or substantially without the formation of free charge carriers by reversible imagewise alignment of at least some of the permanent dipoles present in the recording layer.

Abstract: A thermoreversible recording material having its transparency changed in accordance with its thermal history, in particular the rate of cooling and the temperature to which it has been heated, comprises a matrix material and an organic compound of low molecular weight, wherein the matrix material comprises polyvinyl acetal, and the organic compound of low molecular weight comprises a saturated carboxylic acid or derivative thereof. The matrix material may further contains a material selected from a group consisting of epoxy resin, phenol resin, epoxy compound, aldehyde compound and isocyanate compound. A thermoreversible recording medium comprising the above thermoreversible recording material may be selectively heated by a thermal head or the like to record visual information. The visual information may be erased by heating the medium and cooling it slowly.

Abstract: A photorecording element consists essentially of a transparent substrate, a layer of a macromolecular compound capable of undergoing a reversible change in structure upon exposure to light, deposited by adsorption on the transparent substrate, and a liquid crystal layer disposed directly on the layer of macromolecular compound. A method for the production of the photorecording element comprises applying on a transparent substrate a mixture of a liquid crystal substance with a macromolecular compound capable of undergoing a reversible change in structure upon exposure to light and allowing the applied layer of the mixture to stand at rest or by first applying the macromolecular compound on the transparent substrate and then adding the liquid crystal substance thereto. A liquid crystal cell incorporating the photorecording element is also disclosed.

Abstract: A novel photochromic compound as a photoreactive material making use of photochromism is provided, which compound is expressed by the following formula (1) or (2)): ##STR1## wherein R is alkyl, alkoxy, perfluoroalkyl or cyano; X.sub.1, X.sub.2, X.sub.3, X.sub.4, X.sub.5 and X.sub.6 are each H, halogen, alkyl, alkoxy, cyano, alkanoyloxy or alkyloxycarbonyl, or a substituted or unsubstituted benzene ring is formed by condensation between at adjacent groups among X.sub.1 to X.sub.6 ; Y is Y.sub.1 C=CY.sub.2, O, S, SO, SO.sub.2 or NY.sub.3 wherein Y.sub.1 and Y.sub.2 are each as defined in the case of the above X.sub.1 to X.sub.6 and Y.sub.3 is H, alkyl, alkanoyl, alkyloxycarbonyl or aryl; and the symbol refers to occurrence of E- or Z-isomer, and which compound is useful as rewritable optical memory element or photo-display element and also as solar energy-storage material, duplicating material, masking material, optical filter, toys, etc.

Abstract: A rewritable phase-change type optical information recording medium having a recording film made of a material containing Te or In as a major component and further containing B or C.

Abstract: Disclosed herein is a recording/reproducing method for an optical recording medium comprising a step of heating a recording layer containing a photochromic material and a polymer which are so combined with each other that a photostationary state attained upon irradiation with light of a specific wavelength is varied with temperatures, and a step of applying the light of a specific wavelength to the heated recording layer for bringing the same into a photostationary state and recording information. In order to reproduce the information, a portion of the recording layer which is in a photostationary state is selectively heated, and reproducing light is applied to reproduce recorded and unrecorded states.

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, Sb.sub.2 Te.sub.3 /or Bi.sub.2 Te.sub.3, or GeSe, Sb.sub.2 Se.sub.3 /Bi.sub.2 Se.sub.3 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.

Abstract: An optical recording medium capable of recording, rewriting and erasing information utilizing changes in optical properties is disclosed, which comprises a substrate having thereon a layer of a recording material that changes reversibly in optical properties thereof upon irradiation with light or application of heat, wherein the recording material consists essentially of at least one element of Group Vb of the periodic table selected from the group consisting of As, Sb, and Bi and at least one element of Group VIb of the periodic table selected from the group consisting of S, Se, and Te; and has a composition corresponding to that of a mixture of at least two stoichiometric compounds represented by the chemical formula Vb-hd 2Vib.sub.3 ; and contains at least one of Se and Te.

Abstract: An image recording device which permits repeated thermoreversible recording and erasure of an image, which is useful for creating an image for storage, display or printing of the image or other information. The recording device has a display medium, a recording means to form an image on the display medium, and an erasure means to erase the image formed on the medium. The display medium of the image recording device may have a support member with a recording layer provided on the support member. The display medium has a transparency which is dependent upon its thermal history, and consists essentially of a matrix material of a copolymer of styrene and butadiene, and a saturated carboxylic acid of 10 to 24 carbon atoms. The weight ratio of the matrix material to saturated carboxylic acid in the display medium is from 1:1 to 20:1.

Abstract: An optical phase change media comprises a substrate, an active layer having a crystalline and a liquid state, a dielectric layer and a reflective layer. The active layer is of a thickness which will transmit incident light. The dielectric layer is of a thickness such that light passing through the active layer is reflected by the reflective layer and destructively interferes with the incident light reflected directly off of the active layer, thereby causing the crystalline state of the active layer to absorb more light than the liquid state. The result is that the media experiences reduced temperature during writing.

Abstract: A photochromic material containing a copolymer of a spirobenzothiopyran derivative prepolymer and a liquid crystal prepolymer. In addition, a rewritable optical recording medium using the photochromic material. A rewritable optical recording medium obtained by coating a dispersed material, which is obtained by uniformly dispersing a spirobenzothiopyran derivative compound in a thermoplastic resin, on a substrate. A photochromic material capable of controlling a colored state and a decolorized state in a photon mode or a heat mode using an ultraviolet light source and a near-infrared light source. A rewritable optical recording medium capable of rewriting an information in a photon mode using a semiconductor laser.

Abstract: Optical recording films made from alloys of antimony-tin and a third element exhibit improved properties when formed in an atmosphere containing nitrogen. The amount of nitrogen in the sputtering environment is controlled. Improvements include higher amorphous to crystalline transition temperature and greater stability of the recorded and unrecorded film.

Abstract: An optical information recording medium is disclosed in which the recording layer is a material capable of absorbing energy and being reversibly converted between a substantially non-crystalline or amorphous state and a substantially crystalline state. The recording layer is a Te-Ge-Sb composition which also contains nitrogen. The optical recording medium includes a substrate onto which is sequentially deposited a first dielectric layer, a nitrogen-containing recording layer, a second dielectric layer and a metallic reflecting layer. In order to control the sensitivity of the medium to laser irradiation, the second dielectric layer is graded in thickness and progressively becomes thicker as a function of increasing radius. Alternatively, in another embodiment, the reflecting layer is graded in thickness, and progressively becomes thinner as a function of increasing radius.

Abstract: A method for recording and erasing information by irradiating a specific recording medium with a single laser beam, which is applied with two different intensities respectively for crystallizing a recording layer of the recording medium and for amorphizing a recording layer of the recording medium. According to the present invention, both the recording of information and the erasing of information can be simply performed using a single laser beam by changing only its intensity between the two different laser beam intensities according to a laser beam intensity pattern corresponding to predetermined information.The recording material comprises Sb, Te, Ge and at least one element selected from the group consisting of Pb, Bi, In, Sn and Tl.

Abstract: A recording medium for information comprising a substrate, a recording layer provided on the substrate, in which crystalline phases and amorphous phases are reversibly created in accordance with irradiation energy of a light beam irradiated onto the recording layer, wherein the recording layer includes a ternary alloy having the same composition as an alloy of InTe and In.sub.50-X/2 Sb.sub.50-X/2 Te.sub.X (where X satisfies 20.ltoreq.X.ltoreq.45), i.e.,{In.sub.(100-y)/200 Sb.sub.(100-y)/200 Te.sub.y/100 }.sub.100-z In.sub.z/2 Te.sub.z/2wherein25.ltoreq.y.ltoreq.45 atom %, and0<z.ltoreq.80 atom %, with the proviso that 0<z.ltoreq.60 atom % when y>40 atom % or y<30 atom %.

Abstract: When information recording is conducted by converting a non-colored state of a recording film into a colored state, use is made of a recording light having a wavelength in such a range that an absorbance of the non-colored state is higher than an absorbance of the colored state. When information erasing is conducted by converting a non-colored state of a recording film into a colored state, use is made of an erasing light having a wavelength in such a range that an absorbance of the non-colored state of the recording film is higher than an absorbance of the colored state. Accordingly, the present invention has the advantage of a great change of color being exhibited in the recording film, thus enabling optimal recording and erasing of information.

Abstract: Novel laser-optical recording elements which can be repeatedly erased and recorded on contain recording layers (a) which exhibit enantiotropic, ferroelectric smectic liquid crystalline (S.sub.c*) behavior, so that they can be switched back and forth between two thermodynamically stable, optically distinguishable ferroelectric smectic liquid crystalline S.sub.c* order states on exposure to a laser beam of sufficient luminous power, by applying an external electric field. The recording layers (a) themselves consist mainly or exclusively of novel polymers P having chiral mesogenic side groups.

Abstract: An optical storage medium is disclosed. In general, the storage medium includes a substrate, with a first, expansion layer, a second, reflective layer bonded to the first layer, and a third, retention layer bonded to the second layer, opposite the first layer. An opto-electronic system for recording data is also disclosed, along with a method of manufacture of the storage medium.

Abstract: An optical recording element comprising a thin film optical recording layer of an alloy is disclosed. The alloy is represented by the formula:Sb.sub.x Cd.sub.1-xwherein x is between about 0.68 and 0.83, and the formula:Sb.sub.x Cd.sub.y Sn.sub.z,wherein Sb.sub.x Cd.sub.y Sn.sub.z is within the polygon enclosed by Sb.sub.83 Cd.sub.17 -Sb.sub.46 Cd.sub.24 Sn.sub.30 -Sb.sub.42 Cd.sub.46 Sn.sub.12 -Sb.sub.68 Cd.sub.32 in a ternary Sb-Cd-Sn composition diagram.

Abstract: An optical recording element comprising a thin film of an alloy is disclosed. The alloy is represented by the formulaTe.sub.a (Sb.sub.x Sn.sub.y In.sub.z).sub.1-awherein a is between about 0.38 and 0.62; x is between about 0.05 and 0.65; y divided by z is between about 0.5 and 5; with the proviso that the product of (y+z) and (1-a) is greater than about 0.20. The alloys have improved data stability while retaining excellent write-erase characteristics.

Abstract: A process for preparing a multiple level logic optical memory disks which are erasable upon heating when ion-beam hydrogenation is used for writing informatin on the disk.The process comprises depositing an amorphous film selected from the group consisting of silicon hydride, silicon carbon hydride and silicon nitrogen hydride on a glass substrate using plasma enhanced chemical vapor deposition at temperatures sufficient to ensure good adhesion and high film quality and an optical bandgap of between aboout 1.55 and about 2.0 eV; writing information on these disks by using a laser beam to selectively heat spots of the film to expel hydrogen and change the bandgap and optical absorption of the film; and using a laser beam at a sufficient nm wavelength in order to detect information stored on these disks.

Abstract: An improved optical memory device comprising a substrate and a plurality of optical memory layers made of a photochromic material and formed over the substrate, the plurality of optical memory layers being laminated to each other through a heat conductive transparent film, which is adaptable for high density and/or high capacity recording of information.

Abstract: An optical recording medium, which comprises a recording layer capable of reversibly undergoing a phase change between a crystalline state and an amorphous state by irradiation of an electromagnetic energy, the crystalline state of the recording layer being composed of a single phase of substantially a three-component compound or a higher multi-component compound can attain high speed recording and high speed erasing that cannot be obtained with the conventional optical recording medium.

Abstract: A light-sensitive recording medium using a photochromic material produced at a low cost, without necessity of fixing free rotation of bonds in its cis compound and removing its trans compound, is disclosed, the recording medium comprising a substrate having thereon a recording layer which contains a photochromic material capable of cis-trans isomerization upon irradiation with light, wherein not more than 50 mol % of the photochromic material has a trans configuration when the recording layer is in a color-disappearing state.

Abstract: An optical memory device comprising:a transparent substrate; anda recording film deposited on the transparent substrate, the recording film being formed by preparing a composition in which a diarylethene-type photochromic compound is dispersed in an ultraviolet-curing polyurethaneacrylate resin of solventless type and by curing the composition by an ultraviolet ray irradiation.

Abstract: A novel series of azo polymers, copolymers and polymer blends for reversible optical storage devices are described. Various azobenzenes can be bound in the side chain or within the main chain of long chain polymers such as polyester, polystyrene and poly methacrylates with very short or no spacers to a form amorphous polymers which as a film or deposited on a transparent substrate can be used to record optical information using a linearly polarized laser beam which induces optical anisotropy in the film. The information can be erased thermally by heating above the glass transition temperature, or optically by overwriting with light polarized in a predefined zero direction or with circularly polarized light.

Abstract: A photochromic material containing a copolymer of a spirobenzothiopyran derivative prepolymer and a liquid crystal prepolymer. In addition, a rewritable optical recording medium using the photochromic material. A rewritable optical recording medium obtained by coating a dispersed material, which is obtained by uniformly dispersing a spirobenzothiopyran derivative compound in a thermoplastic resin, on a substrate. A photochromic material capable of controlling a colored state and a decolorized state in a photon mode or a heat mode using an ultraviolet light source and a near-infrared light source. A rewritable optical recording medium capable of rewriting an information in a photon mode using a semiconductor laser.

Abstract: An apparatus for manufacturing an optical memory device, which includes supplying rolls for continuously supplying a sheet-like substrate, a masking endless belt having a plurality of windows of size corresponding to the optical memory device, rolls for moving the sheet-like substrate and the masking endless belt in the same direction and at the same speed, a recording portion forming device for forming recording portions on the substrate through the masking endless belt, a guide track providing device for providing along the substrate guide tracks for guiding a light beam, and a cutting device for cutting the substrate to a predetermined size.

Abstract: A silicate glass article comprising an amount of SiO.sub.2 effective as a network former and,at least one surface of said article having a substantially continuous silver and hydration content over its area, effective to render said surface darkenable upon exposure to electron beam radiation but substantially not thermoplastic,said article having been substantially darkened by electron beam irradiation over at least a portion of at least one surface thereof,and said article having geometric characteristics suitable for functioning as a photomask reticle, optical disk or similar archival storage medium.

Abstract: In accordance with the present invention, there are provided photo-recording media comprising photochromic compounds having been dispersed or dissolved in stretched films or nematic liquid crystals, the transition moment of light absorption of said photochromic compounds being orientated in a definite direction. In the photo-recording media as provided, an information recorded in the photochromic compounds can be read out without destroying the same.

Abstract: Silicate glasses are provided which when exposed to a silver ion exchange surface treatment are writable with electron beams. These glasses contain OD agents and do not require elements having 1-4 d-electrons in the atomic state.

Abstract: A rewritable or repeatedly employable recording medium having a base and a recording layer film provided on said base, characterized in that said recording layer film is formed by a thermotropic cholesteric liquid crystal polyester.

Abstract: The invention describes an optical data storage medium in which the optical contrast of stored data bits is enhanced by the use, as a photosensitive material or as an additional photosensitive material, of a layer of a photochromic fulgide.

Abstract: Provided is an information recording medium, e.g., an optical recording medium, and a method for recording information thereon. The information layer of the recording medium comprises an organo macrocyclic chromophore containing a central hetero atom or two central hydrogen atoms or isotopes of hydrogen, e.g., a naphthalocyanine having silicon as the hetero atom, which chromophore is substituted with at least one substituent conferring film forming properties to the chromophore, e.g., a monomer or oligomeric substituent comprised of acid, amide or ester units. The information layer thereby offers excellent thermomechanical properties and exhibits excellent absorption properties all in a single component material. By utilizing a single component material, the problem of dye/polymer phase separation frequently encountered in dye/polymer mixtures is also overcome.

Abstract: An erasable optical information storage apparatus is disclosed and the process for making such an apparatus is disclosed. The apparatus utilizes the photoabsorption and electrochemical absorption characteristics of the polyaniline class to polymers to provide an easily accessible and erasable information storage unit.

Abstract: The invention relates to an optical data recording method which comprises addressing a recording device using an infra-red laser modulated with a waveform of the information to be recorded, wherein said recording device comprises an infra-red absorbing material and a photochromic fulgide which is converted into its colored form under the influence of the heat absorbed from the laser, and updating the recording by erasing undesired previously recorded data using a laser operation in the visible region of the spectrum.

Abstract: This invention provides an optical information recording medium whose recording thin film is made of three components of GeTe, Sb.sub.2 Te.sub.3 and Sb derived from a GeTe alloy, an Sb.sub.2 Te.sub.3 alloy and excess Sb and which is capable of recording, reproduction and erasure. By this, optical disk files which have a stable cycle characteristic and are practically useful can be realized.