Abstract: A technique of optical card having high information recording density. In the optical cards, there are two types of optical cards having a read-only optical card and an additional recording optical card. Conventionally, separate readers for reproduction have been used due to difference in light reflectivity. In this invention, a light-absorbing layer (50) having light absorbing ability with respect to reading light (300) is arranged between a card side upon which the reading light is incident and a reflective surface of a pattern (21) of an optical data recording section (20), so that the optical cards have interchangeability therebetween in reading.

Abstract: The invention relates to a technique for retouching a pattern which is formed on one side of a substrate and which partially has defects. A method of retouching the pattern, according to the invention, comprises coating the one side of the substrate including the pattern, with a retouching protective membrane, exposing the one side of the substrate, with reference to portions having defects, filling the portions of the exposed one side of the substrate, with retouching material, and removing the retouching protective membrane. One of the retouching protective membrane and the retouching material is made of water-soluble material, while the other is made of oil-soluble material.

Abstract: An optical recording medium includes a silver grain layer containing a large number of blackened fine silver grains and a coloring matter layer containing coloring matter on a base board and the coloring matter has an ability of absorbing near-infrared ray. When laser beam having a density of optical energy more than a boundary which represents a threshold with respect to the density of optical energy is radiated to the optical recording medium, a part of the latter is deformed to form a plurality of convexities which will be utilized as optical recording pit. The recording pits formed in this way are detected by presence or absence of reflection of radiated light whereby the content of optical recorded informations can be read. The optical recording pits are not deformed further irrespective of how long a reading light comprising laser beam having a density of energy less than the threshold is repeatedly radiated to the optical pits.

Abstract: A technique related to color filters to be arranged on the light-receiving surface of a color liquid crystal display device, color video camera, and the like. The color filter consists of a substrate (10) and a colored filter layer (12) formed thereon. The colored filter layer (12) comprises, for example, three groups of filter picture elements (14R), 14G, 14B) having spectral characteristics respectively corresponding to red, green and blue. Each group of filter picture elements are made of polyimide resin and dye contained therein. Further, each group of the filter picture elements (R, G, B) are arranged in direct contact with one surface of the substrate (10) without using any intermediate protecting film. The first group of filter picture elements patterned on one surface of the substrate (10) are subjected to heat treatment at a high temperature of about 250.degree. C., for example, to increase their resistance against the solvent.

Abstract: A magnetic recording medium includes a truth determining code for determining whether the medium is authentic. The truth determining code is indicated by a magnetic polarity at at least an edge of the medium. A method of determining whether the medium is authentic comprises the steps of detecting a magnetic polarity at an edge of the magnetic recording medium, and collating a combination of the magnetic polarity with a proper combination of the magnetic polarity.

Abstract: An optical or magneto-optical recording card is produced using a transfer type optical or magneto-optical recording medium. The transfer type optical or magneto-optical recording medium comprises a base film, a peeling layer, an optical or magneto-optical recording layer and a light permeable adhesive layer which are successively superimposed one above another to constitute a layered structure. A protective layer is adhered to the transfer type optical or magneto-optical recording medium with the aid of an adhesive layer and the base film is then peeled off together with the peeling layer. Next, the protective layer to which the optical or magneto-optical recording layer is adhered is adhesively attached to a card base in such a manner that the optical or magneto-optical recording layer is interposed therebetween whereby an optical or magneto-optical recording card is completely produced. The transfer type recording medium can be preserved in such a state that it is wound about a reel.

Abstract: A method of producing a plurality of masks which are used when ROM type data are written in an optical recording medium for ROM type optical recording cards. The method is practiced by way of steps of producing a mother mask having a preformatting pattern, next, transcribing the preformatting pattern for the mother mask, next, producing a master mask having a required optical recording pattern written therein and next, producing a working mask from the master mask. When the preformatting pattern is prepared in a writable type, writing or inspecting of the master mask or inspecting of the working mask or mother mask can be achieved using a writing/reading apparatus for writable type optical recording cards.

Abstract: A magnetic card wherein visible patterns are written. A magnetic recording layer is formed on a substrate, a sensitizing layer is formed on the magnetic recording layer, a metallic thin layer is formed on the sensitizing layer, a protective layer is formed on the metallic thin layer, an arrangement of magnetic bars is formed on the protective layer at one region of the magnetic card, and at least one information track is formed on the magnetic recording layer at the other region of the magnetic card. The metallic thin layer and the sensitizing layer are configured such that, upon the application of heat by a localized source, the heated portions of the metallic thin layer are dispersed into the sensitizing layer to produce the visible patterns.

Abstract: In an optical card, a card substrate has its rigidity which is sufficient to handle the card substrate independently. The card substrate has a first side which serves as a reading side upon which reading light is incident. An optical-data recording section includes a light-reflective pattern. The optical-data recording section is arranged on one of the first and second sides of the card substrate. Optical data incident upon the optical-data recording section toward the reading side of the card substrate is recorded by the optical-data recording section. A shielding layer is arranged on one of the first and second sides of the card substrate, for shielding the optical-data recording section from a viewer's field of view. The shielding layer has its transmission characteristic with respect to the reading light, which is sufficient to shield light within a visual range and to enable reading of the optical-data recording section.

Abstract: An optical recording card is produced using a transfer type optical recording medium. The transfer type optical recording medium comprises a base film, a peeling layer, an optical recording layer and a light permeable adhesive layer which are successively superimposed one above another to constitute a layered structure. A protective layer is adhered to the transfer type optical recording medium with the aid of an adhesive layer and the base film is then peeled off together with the peeling layer. Next, the protective layer to which the optical recording layer is adhered is adhesively attached to a card base in such a manner that the optical recording layer is interposed therebetween whereby an optical recording card is completely produced. The transfer type recording medium can be preserved in such a state that it is wound about a reel. Accordingly, the transfer type recording medium is adhered to the protective layer when the optical recording card is produced, and thereafter it is adhered to the card base.

Abstract: This invention provides a thermal recording medium which has a metallic thin layer, a heat sensitive layer formed on said metallic thin layer and a contrast layer formed on either said heat sensitive layer or the above metallic thin layer and visually contrasting with the above metallic thin layer.A thermal recording medium having a roughed metallic thin layer can be produced by using a material containing minute particles to form a roughed heat sensitive layer or a roughed contrast layer prior to the formation of the metallic thin layer and depositing it on the roughed heat sensitive layer or the roughed contrast layer.A desired pattern is thermally recorded by heating in said desired pattern the heat sensitive layer and the metallic thin layer of the above thermal recording medium to melt the heated areas of said metallic thin layer and disperse the molten metallic thin layer as fine particles into the heat sensitive layer touching said metallic thin layer thereby destroying it in the above desired pattern.

Abstract: A certification card such as ID card or the like includes a hologram and an optical recording portion. Hologram is such that an amplitude and a phase of a light wave emitted from an object are recorded and an image of the object is rebuilt by emitting light to reproduce of an amplitude and a phase of the thus emmited light. An optical recording technique for use with the card employs data pits which are formed on an optical reflective surface of an optical recording layer. The thus formed data pits are detected by difference in optical reflectivity from the data pits when the object is illuminated by laser beam so that data are read. The card is constituted by adhering a card front substrate to a card rear substrate, and hologram and optical recording portion are formed between the card front substrate and the card rear substrate. The certification card is difficult to falsify and alter and, therefore, has high safety.

Abstract: In a magnetic recording medium, three sorts or more of magnetic patterns being different in the coercive force are combined corresponding to information, and the magnetic pattern with high coercive force is previously magnetized in required direction and the magnetization direction provides a part of the information. In this constitution, the codes for discriminating truth or falsehood of the card cannot be easily deciphered by a magnetic viewer on the market thereby the security can be improved.

Abstract: This optical recording card includes optical recording medium which is formed with optical information patterns each of which has an optical reflective layer and information stored in the optical recording card can be read out in dependency on the difference in optical reflectivity of the optical information pattern. It is not economical that the optical reflective layer of the optical recording card is formed on a base sheet by etching or the like, wherein the base sheet is prepared in the form of a sheet. The optical recording card is produced by way of the steps of forming an optical reflective layer on a continuous base film having large area and then die cutting the assembly of optical reflective layer and base film into a large number of optical recording cards having required dimensions in such a state that the optical recording medium is held between a card base and a protective sheet.

Abstract: The present invention is concerned with a certification card such as ID card or the like including hologram and an optical recording portion.Hologram is such that an amplitude and a phase of light wave emitted from an object are recorded and an image of the object is rebuilt by emitting light to reproduce of an amplitude and a phase of the thus emitted light.On the other hand, optical recording technique is such that data pits are formed on an optical reflective surface of an optical recording layer and the thus formed data pits are detected by difference in optical reflectivity from the data pits when the object is lightened by laser beam so that data are read.According to the present invention a card is constituted by adhering a card front board to a card rear board, and hologram and optical recording portion are formed between the card front board and the card rear board.The such prepared certification card is difficult to be falsified and altered and therefore it has high safety.

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: The invention relates to a scheme for correctly reading data pits with a reader even if an optical recording card is fed slantwise.If the optical recording card is slanted relative to a line sensor for reading the card, the line sensor may ride on two or more data pit columns. However, discriminator pits are formed at the start and end of each data pit column so that the data can be processed after deciding if the optical recording card is disposed slantwise or not.A relatively short data pit column with discriminator pits formed at the start and end thereof is used. A plurality of data pit columns are disposed with a guide bar interposed therebetween. A readout signal from the discriminator pits is used for deciding if the data pit column has been read correctly, whereas a strobe signal read from the guide bar is used for initiating a memory selector.

Abstract: A technique related to color filters to be arranged on the light-receiving surface of a color liquid crystal display device, color video camera, and the like. The color filter consists of a substrate (10) and a colored filter layer (12) formed thereon. The colored filter layer (12) comprises, for example, three groups of filter picture elements (14R, 14G, 14B) having spectral characteristics respectively corresponding to red, green and blue. Each group of filter picture elements are made of polyimide resin and dye contained therein. Further, each group of the filter picture elements (R, G, B) are arranged in direct contact with one surface of the substrate (10) without using any intermediate protecting film. The first group of filter picture elements patterned on one surface of the substrate (10) are subjected to heat treatment at a high temperature of about 250.degree. C., for example, to increase their resistance against the solvent.

Abstract: There is disclosed a system for detecting a difference between an image on a primary sheet and an image on a secondary sheet. A microprocessor unit determines whether corresponding ones of first and second image elements representative respectively of the images on the primary and secondary films differ in optical density from each other below a predetermined level. The two corresponding first and second image elements different above the predetermined level are emphasized in optical density difference and alternately displayed on a display screen at a short time interval, so that the dot of the display screen which alternately display these image elements is caused to flicker.

Abstract: A shock-resistant integrated circuit card arranges an integrated circuit at a marginal edge region of the card where deformation forces are minimized. A flexible circuitboard interconnects the integrated circuit with exterior terminals spaced transversely away from the integrated circuit.