Abstract: An ink jet head has an ink head main body that is constituted of a substrate, spacers that are formed on one side of the substrate, and a roof plate that is joined to the substrate through the spacers. One or more ink passages are independently formed between the substrate and the roof plate. Rows of piezoelectric devices, each of which is made of a plurality of piezoelectric devices aligned along each ink passage, are formed through the respective ink passages. Ac voltages whose phases are different from each other by 90 degrees are applied to the respective piezoelectric devices. Progressive waves, which are excited by the rows of piezoelectric devices, allow ink to move through the ink passage and to be sprayed.

Abstract: A transparent substrate of an optical memory is produced by injection molding using a stamper. Grooves and lands are alternately arranged on the optical memory, for tracking of light converged on the optical memory. The groove width is set in the range of 0.3 .mu.m to 0.4 .mu.m and the groove depth is set in the rage of 80 nm to 100 nm. A decrease in the width of a land at each edge is restrained to 0.2 .mu.m in maximum. With such dimensions, even when the track pitch is set to about 1.4 .mu.m, it is possible to obtain a track crossing signal with intensity sufficient for performing an access operation to a target track. Moreover, since the dimensions bring about an improved reflectance at a land, the optical memory achieves an improved C/N and recording density.

Abstract: A probe is displaced relative to a recording medium according to a drive voltage. A chip is provided at an end of the probe. The chip serves to form pits and projections on a surface of the recording medium according to a recording voltage (Vp2) and serves to output a current signal responsive to the pits and projections with a reproducing voltage (Vp1) applied. A voltage generator generates the recording voltage and the reproducing voltage based on address and data signals. A sample-hold unit samples at a specified frequency a current signal obtained from a no-recording area of the recording medium by the chip and produces an output voltage signal. A reproducing unit demodulates and reproduces increment and decrement of the current signal obtained from a recording area of the recording medium by the chip. A control unit controls recording and reproduction.

Abstract: An information recording and reproducing apparatus of the present invention, in which a tunnel current is utilized for recording information to a recording surface of a recording medium and/or for reproducing information from the recording surface, includes a slider which is arranged on the recording surface and floats above the recording surface by an air flow caused by movement of the recording medium. The slider includes a body having a first surface positioned opposite to the recording surface, a second surface parallel to the first surface, and a third surface oblique to the first and second surfaces. The slider further includes a cantilever having a projecting portion projecting from the body so as to be substantially parallel to the recording surface and a tip for detecting the tunnel current formed on a surface of the projecting portion on the side of the recording surface.

Abstract: An optical disk for use in an optical memory device having guide grooves and pits on one surface thereof, wherein the depth of the guide grooves is different from that of the pits and the distance from the bottom face of each of the guide grooves to the other surface of the optical disk opposite to the one surface of the optical disk on which the guide grooves and pits are disposed is the same as the distance from the bottom face of each of the pits to the other surface of the optical disk opposite to the one surface of the optical disk on which the guide grooves and pits are disposed, and a method for the production of optical memory master plates that are used for the production of the above-mentioned optical disk.

Abstract: An ink jet head has an ink head main body that is constituted of a substrate, spacers that are formed on one side of the substrate, and a roof plate that is joined to the substrate through the spacers. One or more ink passages are independently formed between the substrate and the roof plate. Rows of piezoelectric devices, each of which is made of a plurality of piezoelectric devices aligned along each ink passage, are formed through the respective ink passages. Ac voltages whose phases are different from each other by 90 degrees are applied to the respective piezoelectric devices. Progressive waves, which are excited by the rows of piezoelectric devices, allow ink to move through the ink passage and to be sprayed.

Abstract: An optical disk including a transparent plastic substrate, a recording film formed on an one side surface of said substrate, a first protective film covering said recording film, and a moisture-impermeable film formed on the other side surface of said substrate via or not via an intermediate film.

Abstract: A method for manufacturing an optical memory element including the steps of disposing a resist film on a substrate, placing a photo-mask carrying a guide groove pattern on the resist film so as to position the photo-mask over a predetermined position of the substrate, forming a guide groove pattern latent image on the resist film, developing the guide groove pattern latent image formed on the resist film, conducting an etching operation through the developed guide groove pattern as to form guide grooves in the substrate, removing the resist film from the substrate, and disposing a recording medium layer on the substrate having the guide grooves formed therein.

Abstract: An optical recording element comprising a recording medium which includes an information recording area formed at every unit in a non-continuous condition, the recording medium further including sample pits disposed at intervals of a fixed distance for providing basic information about the locations of the recording units in same track. Each sample pit comprises a plurality of pits disposed next to the sequence of the recording units so that the spacing between the pits differs from the spacing between the recording units. At least one of the plurality of pits is a long-sized inclined pit which is inclined at an angle in the range of 6.degree. to 80.degree. to a recording track.

Abstract: A photo-mask and a method of manufacturing a photo-mask, which includes the steps of applying a resist film onto a substrate of quartz, glass and the like, subjecting the resist film to light exposure and development to form a fine resist pattern, etching the mask substrate covered by the fine resist pattern, causing a non-light transmitting thin film of Cr, Ta, etc. to adhere thereon by vapor deposition, sputtering and the like, and removing the thin film on the resist pattern together with the resist film, thereby to form the photo-mask.

Abstract: An optical disc includes a recording film formed on one surface of a disc-shaped plastics substrate having light transmission properties, and a coating film formed on the other surface of the substrate to which an optical beam is applied, in which the plastics substrate is made by injection molding and a barrier, such as a U-shaped annular groove or ridge, is circumferentially formed on the other surface, at a radial distance which is the distance from a center position to a joint position of an injection mold, and a method for manufacturing the same.

Abstract: A tracking system for positioning a light spot onto a magneto optic or optical disc having a beam guide track preformatted thereon comprises a main light beam and two auxiliary light beams, and a circuit for subtracting a low frequency component of a difference between the tracking error signals, detected by the respective auxiliary light beams and the main light beam, from a tracking error signal detected by the main light beam.

Abstract: A photo-mask comprises a light-permeable substrate, a plurality of light-shielding films that are disposed on the substrate, the light-shielding films forming a mask pattern, and a light-permeable protective film that is disposed over the surface of the substrate including the light-shielding films so as to protect the light-shielding films.

Abstract: An optical disk for use in an optical memory device having guide grooves and pits on one surface thereof, wherein the depth of the guide grooves is different from that of the pits and the distance from the bottom face of each of the guide grooves to the other surface of the optical disk opposite to the one surface of the optical disk on which the guide grooves and pits are disposed is the same as the distance from the bottom face of each of the pits to the other surface of the optical disk opposite to the one surface of the optical disk on which the guide grooves and pits are disposed, and a method for the production of optical memory master plates that are used for the production of the above-mentioned optical disk.

Abstract: A microrelay including a substrate having a pair of fixed contacts fixed on a surface thereof and a movable section having a pair of movable contacts opposed to the pair of fixed contacts. The movable section includes a frame for fixing the movable section to the substrate; a movable body having the pair of movable contacts and a pair of magnetic bodies; and a coupling section for pivotally supporting the movable body to the frame. The substrate has a pair of magnetic force generating devices for supplying the pair of magnetic bodies with a magnetic force, thereby selectively causing contact between one of the pair of movable contacts and the fixed contact opposed to the one of the pair of movable contacts; and a magnetic force controlling device for applying the magnetic force generated by each of the pair of magnetic force generating devices only to the magnetic body corresponding to each of the magnetic force generating device.

Abstract: An optical disk including concentric or spiral grooves, a first series of pits formed in the interrupted portions, and a second series of pits formed in portions of lands. Both of the first and second series of pits represent address information. The portions of the lands and the interrupted portions of the grooves are located in different radial directions. With this arrangement, even when the optical disk has a reduced track pitch, accurate address information is obtained, achieving a high-density recording optical disk.

Abstract: An optical memory device comprising a substrate and guide tracks having a depth of .lambda./8n or less formed on said substrate, wherein .lambda. is the wavelength of laser light used for the optical memory device, and n is the refraction index of the guide track portion of the substrate.

Abstract: An optical recording element comprising a recording medium which includes an information recording area formed at every unit in a non-continuous condition, the recording medium further including sample pits disposed at intervals of a fixed distance for providing basic information about the locations of the recording units in same track. Each sample pit comprises a plurality of pits disposed next to the sequence of the recording units so that the spacing between the pits differs from the spacing between the recording units. At least one of the plurality of pits is a long-sized inclined pit which is inclined at an angle in the range of 6.degree. to 80.degree. to a recording track.

Abstract: A method of manufacturing a photomask for an optical memory, the photomask having two types of pattern where guide tracks and formatting pits are different in amount of optical transmissions, including the steps of (a) forming on a transparent substrate a thin film of which light transmission amount depends upon its thickness; (b) forming a photoresist film on the thin film; (c) exposing the photoresist film to light with different light intensities depending selectively on the guide tracks or formatting pits; (d) eliminating the photoresist film exposed to the more intense light by the development till the thin film becomes surface; (e) etching the thin film exposed to the more intense light and surfaced; (f) eliminating the photoresist film till the thin film exposed to the less intense light becomes surface; (g) etching away the thin film exposed to the more intense light and surfaced till the transparent substrate becomes surface; and (h) eliminating the remnant photoresist.