Abstract: A wiring glass substrate includes a glass substrate formed of glass and having a plurality of holes formed at predetermined positions, bumps so formed as to be connected to a conductive material filling the holes and wirings formed on a surface opposite to a surface having the bumps formed thereon and electrically connecting a plurality of connection terminals arranged in intervals different from intervals of the holes to the conductive material. The shape of the conductive material is porous and porous electrodes are bonded to the inner wall surfaces of the holes by an anchor effect to increase the strength of the glass substrate.

Abstract: A temperature sensor (131) detects a temperature of a spindle motor (121) of a rotary drive unit (120) for rotating a disk-shaped recording medium (1), and a temperature information acquiring unit (134A) acquires the temperatures as temperature information. An eccentricity detector (132) detects a drive voltage level, and an eccentricity information acquiring unit (134B) acquires the drive voltage level as eccentricity information. When a determining unit (134C) determines that the temperature is higher than a predetermined temperature or that the drive voltage level is higher than a predetermined voltage, a servo controller (133) switches a rotation mode from constant liner velocity to constant angular velocity. That enables stable information processing over a long time with a simple strucure for constant linear velocity.

Abstract: A glass substrate for a magnetic disk contains a transition metal. The substrate, which is subjected to formation of zone texturing by irradiating the substrate with a laser beam, has a high mechanical strength even if it is not chemically strengthened. The glass substrate contains a transition metal element and has a transmittance of 10% of less for light in a wavelength range of 300 to 2000 nm. The surface roughness of an information recording surface portion thereof is 2.0 nm or less. In addition to a transition metal element, the glass substrate may include a rare earth metal element.

Abstract: A wiring glass substrate includes a glass substrate formed of glass and having a plurality of holes formed at predetermined positions, bumps so formed as to be connected to a conductive material filling the holes and wirings formed on a surface opposite to a surface having the bumps formed thereon and electrically connecting a plurality of connection terminals arranged in intervals different from intervals of the holes to the conductive material. The shape of the conductive material is porous and porous electrodes are bonded to the inner wall surfaces of the holes by an anchor effect to increase the strength of the glass substrate.

Abstract: A wiring glass substrate includes a glass substrate formed of glass and having a plurality of holes formed at predetermined positions, bumps so formed as to be connected to a conductive material filling the holes and wirings formed on a surface opposite to a surface having the bumps formed thereon and electrically connecting a plurality of connection terminals arranged in intervals different from intervals of the holes to the conductive material. The shape of the conductive material is porous and porous electrodes are bonded to the inner wall surfaces of the holes by an anchor effect to increase the strength of the glass substrate.

Abstract: For reproducing and/or recording information from/onto an optical disc, a pickup is used to detect a target track on the disc through an optical beam. In carriage servo control, movement of the pickup is servo-controlled in the radial direction of the optical disc. In this control, a tracking error signal is produced by a preamplifier. A pulse signal is produced, in which the period of the pulse signal is set to a constant amount corresponding to the accuracy of movement of the pickup. Based on the pulse signal and the tracking error signal, a carriage control signal to move the pickup is produced. The carriage control signal is then supplied to a carriage motor by a driver, so that the pickup is moved.

Abstract: An information recording medium reproducing system has an insertion opening, a recording medium storing portion and a medium carrying device. Photodetectors are provided for detecting passing of the recording medium and for producing a passing signal when the medium passes. A controller is provided for controlling operation of the medium carrying device. The controller applies a discharge signal to the medium carrying device when the passing signal is not produced within a predetermined time, whereby the medium carrying device is actuated in discharge operation.

Abstract: A glass substrate for a magnetic disk contains a transition metal. The substrate, which is subjected to formation of zone texturing by irradiating the substrate with a laser beam, has a high mechanical strength even if it is not chemically strengthened. The glass substrate contains a transition metal element and has a transmittance of 10% of less for light in a wavelength range of 300 to 2000 nm. The surface roughness of an information recording surface portion thereof is 2.0 nm or less. In addition to a transition metal element, the glass substrate may include a rare earth metal element.

Abstract: A glass substrate for a magnetic disk contains a transition metal. The substrate, which is subjected to formation of zone texturing by irradiating the substrate with a laser beam, has a high mechanical strength even if it is not chemically strengthened. The glass substrate contains a transition metal element and has a transmittance of 10% of less for light in a wavelength range of 300 to 2000 nm. The surface roughness of an information recording surface portion thereof is 2.0 nm or less. In addition to a transition metal element, the glass substrate may include a rare earth metal element.

Abstract: An aluminum nitride sintered body produced by sintering under pressure of a powder composition comprising aluminum nitride and 5 to 30% by weight of at least one sintering aid selected from the group consisting of Nd, Sm, Eu, Er, Dy, Gd, Pr and Yb, per 100% by weight of the powders of aluminum nitride and the sintering aid, wherein the amount of the sintering aid is a conversion value as oxides of the elements, the sintering body that has been subjected to mirror-polishing having a surface roughness R max of 0.2 ?m or less and a thermal conductivity of 200 (W/mK) or more.

Abstract: A glass substrate for a magnetic disk contains a transition metal. The substrate, which is subjected to formation of zone texturing by irradiating the substrate with a laser beam, has a high mechanical strength even if it is not chemically strengthened. The glass substrate contains a transition metal element and has a transmittance of 10% of less for light in a wavelength range of 300 to 2000 nm. The surface roughness of an information recording surface portion thereof is 2.0 nm or less. In addition to a transition metal element, the glass substrate may include a rare earth metal element.

Abstract: In the manufacture of a gas discharge type display panel, by applying a sealing operation along with an exhausting operation, the sealing glass 14 is broken down by a pressure difference between the inside and outside of the panel, and thus, the clearance gap between the substrates can be controlled as desired. In addition, the gaseous component that is unnecessary for the discharge operation is exhausted by setting the temperature of the amorphous sealing glass to exceed its softening-point and be no more than its working point. In the structure of the gas discharge type display panel, a protruding portion having a radius of curvature between 0.1 mm and 1 mm is formed on the sealing glass to reduce the dispersion in the thickness direction of the sealing glass, or the cross-sectional shape of the sealing glass is made convex both at its inside end part and its outside end part.

Abstract: A temperature sensor (131) detects a temperature of a spindle motor (121) of a rotary drive unit (120) for rotating a disk-shaped recording medium (1), and a temperature information acquiring unit (134A) acquires the temperatures as temperature information. An eccentricity detector (132) detects a drive voltage level, and an eccentricity information acquiring unit (134B) acquires the drive voltage level as eccentricity information. When a determining unit (134C) determines that the temperature is higher than a predetermined temperature or that the drive voltage level is higher than a predetermined voltage, a servo controller (133) switches a rotation mode from constant liner velocity to constant angular velocity. That enables stable information processing over a long time with a simple strucure for constant linear velocity.

Abstract: Partial information such as the beginning data of each of chapters is read from a CD and written in a HDD 10 at a higher speed than that in a normal reproduction while the normal reproduction is carried out using a buffer memory 8. After the chapters relative to all CDs have been written in the HDD 10, reproduction is carried out in switching between the information remaining in the HDD 10 and the information included in the CD. This configuration makes it unnecessary to record the information beforehand, and permits an unreproduciable blank in reproduction to be filled with audio information during track search or CD change while the reproduction is carried out normally.

Abstract: An information recording medium reproducing system has an insertion opening, a recording medium storing portion and a medium carrying device. Photodetectors are provided for detecting passing of the recording medium and for producing a passing signal when the medium passes. A controller is provided for controlling operation of the medium carrying device. The controller applies a discharge signal to the medium carrying device when the passing signal is not produced within a predetermined time, whereby the medium carrying device is actuated in discharge operation.

Abstract: A wiring glass substrate includes a glass substrate formed of glass and having a plurality of holes formed at predetermined positions, bumps so formed as to be connected to a conductive material filling the holes and wirings formed on a surface opposite to a surface having the bumps formed thereon and electrically connecting a plurality of connection terminals arranged in intervals different from intervals of the holes to the conductive material. The shape of the conductive material is porous and porous electrodes are bonded to the inner wall surfaces of the holes by an anchor effect to increase the strength of the glass substrate.

Abstract: A glass substrate for a magnetic disk contains a transition metal. The substrate, which is subjected to formation of zone texturing by irradiating the substrate with a laser beam, has a high mechanical strength even if it is not chemically strengthened. The glass substrate contains a transition metal element and has a transmittance of 10% or less for light in a wavelength range of 300 to 2000 nm. The surface roughness of an information recording surface portion thereof is 2.0 nm or less. In addition to a transition metal element, the glass substrate may include a rare earth metal element.

Abstract: A glass including SiO2, Na2O, MgO, Al2O3, and cobalt oxide, wherein the cobalt oxide is 4.5-85 wt % as an oxide of CoO or 4.9-91 wt % as an oxide of Co3O4.

Abstract: A glass including SiO2, Na2O, MgO, Al2O3, and cobalt oxide, wherein the cobalt oxide is 4.5-85 wt % as an oxide of CoO or 4.9-91 wt % as an oxide of Co3O4.

Abstract: An aluminum nitride sintered body produced by sintering under pressure of a powder composition comprising aluminum nitride and 5 to 30% by weight of at least one sintering aid selected from the group consisting of Nd, Sm, Eu, Er, Dy, Gd, Pr and Yb, per 100% by weight of the powders of aluminum nitride and the sintering aid, wherein the amount of the sintering aid is a conversion value as oxides of the elements, the sintering body that has been subjected to mirror-polishing having a surface roughness R max of 0.2 &mgr;m or less and a thermal conductivity of 200 (W/mK) or more.