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 disc comprising a resin layer of resin material formed on a relatively rough surface of each transparent disc substrates, the resin material having approximately the same refractive index of light as the refractive index of the transparent disc substrate, and a recording layer formed on each of said resin layers. Accordingly, the optical recording disc enables a decrease in production costs and to write and read an information signal into and from the recording layer at an improved signal to noise ratio as compared to a conventional optical recording disc.

Abstract: An optical information recording medium having at least a transparent substrate and a recording layer and capable of recording an information by irradiating the recording layer with laser beams from the transparent substrate side, wherein a protective film having hygroscopic property is formed on a light incident surface of the transparent substrate so that it can be stripped therefrom.

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 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: There is disclosed an optical information recording medium comprising forming at least a recording or reflecting film on one surface of a substrate, wherein an plasma-polymerized film of a halogen-containing resin is formed on at least one of the surface of the substrate or the outer surface of the recording or reflecting film. The medium may further include an additional UV-curing film which is formed on any of the surface of the substrate or plasma-polymerized film of halogen-containing resin on the surface of the substrate, the recording or reflecting film, or the peripheries of the substrate and protective film.

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 medium is provided which comprises a diacetylene derivative compound and at least one compound selected from the group consisting of azulenium salt compounds, pyrylium dyes, diene compounds, croconic methines, and polymethine compounds. An optical recording method is also provided which comprises a step of writing by irradiating with a radiation ray corresponding to a recording information an optical recording medium comprising a polydiacetylene derivative compound and a compound selected from the above-mentioned group.

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: Optical recording media disclosed herein are excellent in recording sensitivity as well as in the adhesion of the substrate to the recording layer, said substrate consisting of a random copolymer of ethylene and a cycloolefin and having a specific structure.

Abstract: A write-once type filled up with any fillers optical data recording medium provided with recording layers for a melting and diffusion recording system is disclosed, wherein a protective layer is formed between the recording layers or between the recording layer and another plate shaped member, the protective layer being composed of a member which is not adversely effected by a melting and recording operation and is not warped by changes of external conditions.

Abstract: A compatible optical disk in which information can be reproduced by a player normally used exclusively for reproduction, and writing, rewriting and erasure can be performed, comprises a recording film material characterized in that the reflectivity of a flat portion of the disk is lower than 50% in an erased or unrecorded state and the reflectivity of a recorded area is increased by recording by an irradiation of light, a light beam-guiding groove (12) formed on the surface of the disk substrate so that information is recorded or read out along the trough portion (12) or crest portion (17) of the guiding groove, and the reflectivity is enhanced in the crest portion (17) between the troughs or in the trough portion (12) between the crests.

Abstract: This disclosure concerns protective overcoatings for an information storage record which includes an information-layer adapted for optical data recording. The protective overcoatings are transparent to recording radiation and especially adapted to enhance service life and recording characteristics.A typical coating comprises the polymerization product of a formulation including at least one radiation-cured "bulk resin" (e.g, an acrylated epoxy or an acrylate monomer or pre-polymer), plus an associated non-yellowing photo-initiator, a non-yellowing adhesion-promoter and related coating-constituents.Once applied, this coating is cured by exposure to UV radiation such as to cure it without heating it significantly so that said radiation functions as the sole or principal polymerizing agent, acting quickly, and with little or no supplemental heat, and without extended "tackiness". This formulation will readily "level" to render the desired coating to serve as a mechanical/chemical barrier.

Abstract: A photographic contact printing process is disclosed having application in the mass production of replicate video discs from a master disc, and other applications wherein it is desired to replicate micro-detail over a relatively large area. A problem with conventional contact printing from a mask to a photographic medium is one of maintaining intimate contact over a relatively large area since dust, dirt, etc., are almost impossible to completely eliminate in any practical manner. In accordance with the present invention, a contact printing process is provided wherein intimate contact is not necessary for making high quality contact prints. The present invention recognizes that in contact printing information from a master disc to a replicate disc, the contact printing process is significantly less sensitive to imperfect contact between the master disc and the replicate disc if one employs a replicate disc comprising a photosensitive material having a certain optical properties.

Abstract: A substrate for an information recording medium having an uneven preformat on its face side and a specular surface on its rear side is characterized by having a degree of crosslinking which is higher at the specular surface than the face side having the uneven preformat. Methods for producing this substrate are also disclosed.

Abstract: An optical disc is disclosed in which a pair of circular disc substrates are arranged in confronted relation with each other with their signal recording layers being directed inwardly and are bonded to each other through spacers at inner and outer peripheral portions. A vent hole is formed in a main surface of one of the disc substrates. A disc label is bonded on the disc substrate so as to cover the vent hole.

Abstract: An optical recording medium for writing and reading information by use of a beam of light comprises an optical recording layer comprising a light-reflective layer and a light-absorptive layer having been preformatted in the form of grooves.

Abstract: An image forming medium is provided which has an image forming layer comprising a monomolecular film of a diacetylene derivative compound or its built-up film and a radiation absorbing layer. The diacetylene derivative compound may be polymeric. An image forming device employing the image forming medium is also provided.

Abstract: An improvement of an information recording medium comprising a disc-shaped resin substrate having an inner-side non-recording zone and an outer-side non-recording zone, a laser-sensitive recording layer, and a flexible resin film (for protection of the recording layer, having protruded and depressed portions on at least the surface facing the recording layer is disclosed. The improvement comprises joining the substrate and the flexible resin to each other on the inner-side and outer-side non-recording zones through fusion by ultrasonic welding or thermal welding in such manner that at least one joining of the flexible resin film to the substrate on the outer-side non-recording zone and the inner-side non-recording zone is effected through a fused portion in the form of a discontinuous ring.

Abstract: A photosensitive recording material for recording information by means of a local change in the optical properties of a recording layer under the action of light having a high energy density, and a process for its preparation.

Abstract: An optical disk and method of preparing it in which a macromolecular substrate has information bits mechanically formed on its surface and a reflective metallic reflective film is deposited thereover. The grain size of the metallic reflective film is kept to less than 50 nanometers by depositing at a rate of no more than 1.5 nanometers per second.

Abstract: Recording and erasing optical information can be done by using an alloy film capable of forming two stable crystalline states differing in crystal texture and optical characteristics by being irradiated with optical energies under different conditions. The memory film includes 35-45 atom % of Indium (In) and 55-65 atom % of antimony (Sb).

Abstract: A method of and a photomask for manufacturing an optical memory element. The manufacturing method includes the steps of: subjecting a positive type photoresist coated on a glass substrate to exposure, by using the photomask capable of irradiating light onto a portion of the photoresist other than the remaining portion, for forming pits on the glass substrate such that the portion of the photoresist is solubilized against developing solution; developing the photoresist by using the developing solution so as to remove the portion of the photoresist; and etching the glass substrate so as to directly form, as convex portions, the pits on a surface of the glass substrate.

Abstract: A vitreous film containing, e.g., 30-90 wt. % of Sn, 1-20 wt. % of P, 0.1-20 wt. % of Pb, 2-30 wt. % of 0 and 5-35 wt. % of F is formed by vapor deposition on a substrate such as glass, metal, plastic or ceramic. A light-absorbing substance can be incorporated in the vitreous film to provide a recording layer for a heat-mode optical recording medium capable of causing decoloration or formation of pits on irradiation with a laser beam.

Abstract: In an optical data storage medium comprising a resin, substrate, a primary coat formed thereon and a recording layer of a dye decomposable by a laser beam formed on the primary coat, said primary coat is a silicone resin layer whose surface had been subjected to a plasma treatment. The primary coat prevents the substrate from attack by solvent for forming the recording layer, and enables the recording layer to be uniform in thickness with good adhesion.

Abstract: An optical disk comprising a pair of substrates, each having a recording surface and a reflective layer in super-position on one side, is disclosed. Such an optical disk has satisfactory shear adhesive strength and peeling strength under high temperature and high moisture conditions.

Abstract: Optical information active layer mainly composed of a quaternary system of Te-Ge-Sn-Au, with composition ratios of Te, Ge and Sn that lie within an area represented by points A B C D and E on FIG. 1, with an additional amount of Au that is 1-40 atomic % of the quaternary system of Te-Ge-Sn-Au. The optical information active layer can be melted readily by a laser diode thereby achieving a high recording sensitivity, because it contains Te.sub.2 Au alloy having low melting point, CHR and erasability after repeated use and long term storage are small, and since excessive Te in the information active layer is stabilized by formings of Ge Te Su Te and Au Te.

Abstract: A photosensitive recording material for recording information by means of a local change in the optical properties of a recording layer under the action of light having a high energy density, and a process for its preparation.

Abstract: A process for producing an information recording medium such as an optical disc comprises the steps: putting a disc-shaped flexible resin film having a hole at its central part upon a surface of the recording layer-side of a disc-shaped resin substrate; placing them on a ultrasonic welding machine between its applying horn and its receiving tool in such a manner that the resin film and the applying horn are opposed to each other, wherein the horn has a ring-shaped protrusion provided with a raised portion; and applying ultrasonic wave to them while pressing the resin film to weld the resin film to the substrate.

Abstract: A recording method is provided which comprises irradiating a recording medium having a recording layer containing a diacetylene derivative compound with a laser beam having a wavelength of 420 to 800 nm according to an input information to allow irradiated portions of the recording medium to cause a color change and thereby to conduct recording. A recording medium for the recording method is also provided.

Abstract: An optical information recording medium is disclosed which comprises a pair of substrates at least one of which has a recording layer on one side thereof and which are placed opposingly to each other so that said recording layer is positioned on the inside and are bonded to each other by adhesive layer(s) with or without spacer(s) therebetween to form a sealed structure, wherein said adhesive layer is composed of a cured adhesive material formed from (a) an epoxy resin, (b) a photolyzable organosilicon compound and (c) an aluminum complex compound, said photolyzable organosilicon compound being a silicon compound having at least one phenyl group which has at least one fluorine atom and at least one o-nitrobenzyloxy group which may have a substituent.

Abstract: An optical recording-reproducing method comprising the step of irradiating a radiation for polymerization on an optical recording medium having a recording layer containing at least one selected from the group consisting of azulenium salt compounds, pyrylium dyes, diene compounds, croconic methine dyes and polymethine compounds (hereinafter called the group B) and a diacetylene derivative compound; the step of irradiating a radiation corresponding to a recording information to thereby change the color at the irradiated portion of the recording layer; and the step of reading the recorded information by irradiating a reading light with a shorter wavelength than said radiation on said recording layer. Also, an optical recording-reproducing device utilizes the above-mentioned method.

Abstract: An optical recording disc, such as a compact disc, having a non-playback side including a write-in region available for adding a message or an illustration so that it can be provided with such one and only design as each individual consumer may desire and it is suitable for a gift.

Abstract: An erasable optical data storage medium has an integral recording layer including an expansion zone and a retention zone having different optical and thermal-mechanical properties. A uniform integral layer of dyed polymer material has the dye leached out of the surface region and a second dye diffused into the surface region to create a retention zone. The retention zone has a higher elastic modulus and glass transition temperature than the underlying expansion zone and is adapted to absorb and transmit light which is centered about a different wavelength than the expansion zone. The medium is adapted to be used with a non-ablative and non-vesicular method to create and erase optically detectable deformations in the retention zone.

Abstract: An optical recording medium made up of a substrate and an electromagnetic radiation sensitive layer consisting essentially of a sulfur compound as a matrix and a substance (such as, for example, Te, Pb, Au, Sn, As, Bi, In, C) which is subjected to heat action from absorption of electromagnetic radiation and brings about optical changes by such heat action.

Abstract: An optical data storage medium includes a triple layer recording structure having an expansion layer, a retention layer and a very thin reflective layer interposed between the retention and expansion layers. The three layers are strongly bonded together so that the thermally and mechanically active expansion and retention layers can mechanically act upon each other through the intermediate reflective layer. The expansion and retention layers are dyed to selectively pass or absorb light of preselected wavelengths. The thin reflective layer is adapted to partially pass and partially reflect light of preselected wavelengths.

Abstract: In an optical recording disk wherein a resin layer cured with ultraviolet radiation is provided on a surface of a transparent substrate, the present invention consists in that a material having a heat distortion temperature of at least 65.degree. C. is employed for the ultraviolet-cured resin layer. The appearance of wrinkles on a UV-cured resin surface is suppressed, whereby an optical recording disk of high carrier-to-noise ratio and long lifetime can be provided.

Abstract: The invention relates to a process for producing supports intended for the optical recording and reading of information. A layer containing a diazo compound is deposited onto a metallized substrate. Recording is obtained by exposing the support to light through a mask, the exposed zones of the layer of diazo compound being decomposed. Dry development in ammonia vapors shows up transparent zones and opaque zones corresponding to the information.

Abstract: A semi-permanent disc protector for shielding an optical disc against surface scratches. The disc protector comprises a transparent annular sheet of a cellulose triacetate film having an inner ring of adhesive adjacent to the center hole of the protector and an outer ring of adhesive adjacent to the outer circumference of the protector. The protector may be applied to either side of an optical disc. When applied to the data-read side of a disc, the rings of adhesive are so disposed that they do not obscure the data region of the disc. The disc protector is applied to the disc with the aid of a centering adapter that insures concentricity of the disc and protector.

Abstract: An improvement is disclosed relating to optical data storage media having two thermo-optically active layers which absorb light at distinct wavelengths and expansion layer in which data appear as bulges formed upon the absorption of light, and a retention layer which fixes such bulges inplace until it is selectively heated to a rubbery state permitting relaxation of the expansion layer and the consequent disappearance of the bulges. In accordance with the improvement, the retention layer is modified so that it absorbs a controlled amount of light at the wavelength which is absorbed by the expansion layer, with the result that it absorbs light at both wavelengths rather than just one. Direct heating of both layers by light absorption during recordation, and accordingly a faster recordation response, are thus achieved.

Abstract: An improved art of producing an optical recording medium by utilizing a photo-etching technique is disclosed. Pits pattern of address for guide groove and sector on each of tracks of optical recording medium to be preformatted is formed in accordance with a photo-etching process or a resist lift-off process. A film of optical recording medium is formed on a transparent base plate and it is then subjected to photo-etching process or alternatively to resist lift-off process to form preformatted pits pattern.

Abstract: An optical information recording disk and optical information recording disk apparatus which increase the recording capacity of data recorded on the disk, and are capable of fast recording and reproduction. Logical tracks are arranged by sequentially merging physical tracks starting at the inner portion of the disk and physical tracks starting at the outer portion, and the number of sectors on corresponding tracks recorded at a constant linear density is invariably constant on the basis of the relation of arithmetical series. Consequently, the inventive system, despite of the MCAV system of constant disk speed, achieves track access and fast data transfer comparable with the conventional CAV system.

Abstract: An optical information recording carrier comprises an optical recording layer provided on a transparent substrate, a film coating layer laminated with out adhesion on said optical recording layer, and further a fixing layer laminated thereon to fix said film coating layer.

Abstract: An optical disk is provided which comprises two sheets of substrates; or two sheets of substrate and a reinforcing plate or a reinforcing rim; or one sheet of substrate and a reinforcing plate; which are bonded to form an integrated body having a spacer interposed therebetween, said spacer being made of elastomeric foam having a specific gravity of not more than 1.5 and an expansion ratio of not less than 1.5 as the material of the said spacer. This optical disk has a high adaptability of the drive and exhibits a high reliability, i.e. excellent vibration restricting performance, thereby being possible to provide a stable and highly accurate information processing.

Abstract: An optical information recording medium is disclosed, which comprises a pair of disc-shaped substrates, at least one of the substrates having a recording layer comprising an organic dye compound on one side thereof, which are disposed so as to face each other, with the recording layer positioned therebetween, with or without a space between the two substrates, by sealing with an adhesive agent comprising an alicyclic epoxy resin component having general formula ##STR1## where R.sup.1 .about.R.sup.9 each represent hydrogen, an alkyl group having 1 to 4 carbon atoms, or halogen; and R represents (CH.sub.2).sub.n, where n is an integer of 1 to 4, ##STR2## and a composite catalyst comprising a photo-decomposition organic silicon compound and a metal complex.

Abstract: An optical recording method is provided which comprises a step of irradiating light corresponding to recording information on the optical recording medium having a recording layer containing at least one selected from the group consisting of azulenium salt compounds, pyrylium dyes, diene compounds, croconic methine dyes or polymethine compounds and a diacetylene derivative compound to thereby form a pit on said recording layer.

Abstract: There is disclosed a bubble-mode data-rewritable optical disc, which has a transparent substrate and a recording layer, formed on the substrate, for storing data to be optically rewritable. The substrate is at least partially formed of an organic material, which releases a gas component when it is heated at a radiation region of a data recording light beam. The recording layer is deposited on the substrate by co-sputtering or co-vacuum evaporation. The recording layer is made of a specific amorphous material containing silicon and fine metal particles. When the gas component is released from the substrate, the recording layer is deformed to be locally peeled off out of the substrate by pressure of the gas component, thus forming a protuberance. In a data erasing mode, a data erasing light beam is radiated onto the recording layer, which is then deformed so as to cause the protuberance to disappear, and has a substantially flat surface, thereby erasing the stored information.

Abstract: Optical data storage media of various technologies, including those with multiple layers of varying absorptivities of light as well as those which are grooved to facilitate tracking, are improved by combining the absorptivity differences with height variations in the interface between the layers (and thereby the relative thicknesses of the layers). The result is a means of varying in a spatial manner in the media themselves the rate at which such media absorb energy. This offers a variety of benefits in both recordation and reading, including helping to focus the heat generated by incident recording beams, increasing tracking sensitivity for both recordation and reading, and preformatting the media as a guide for both recordation and reading.

Abstract: An optical information recording and reproducing disc information has a substrate in the surface of which are formed signal recording grooves and cue signal recording pits. A light-absorbing thin film is formed on the surface of the substrate, the optical characteristics of the light-absorbing film being changeable thermally through irradiation by a light beam. The pitches of the grooves and pits, as well as the widths of the grooves and pits, are determined to meet specific conditions in relation to the diameter of the laser beam which is used for recording and reproduction of the signals. In addition, the depths of the grooves and pits are determined suitably in relation to the wavelength of the laser beam. With this arrangement, it is possible to attain a high quality of reproduction of information from the disc.

Abstract: An erasable optical data storage medium including a substrate and a dual layer of a first material and a second material on the substrate. The dual layer is susceptible to expansion and contraction, to writing data thermally, to erasing data thermally and mechanically, and to reading data optically, the first material and the second material, respectively, being bonded together and remaining in the same physical state upon the expansion and relaxation of the dual layer. Methods and apparatus are also disclosed for recording data bits on the medium.