Abstract: A light deflection element has a pair of oscillating elements (6) and (7) having arms (6a) and (6b), and (7a) and (7b). respectively, the outer ends of which are fixed to a pair of supports (3) and (4) of a base (2), and the inner ends of which are free ends, a reflective mirror (8) disposed between arms (6a) and (6b), and arms (7a) and (7b) of the pair of oscillating elements (6) and (7), pairs of torsion springs (9a and 9b) and torsion springs (10a) and (10b), linking the inner ends of the arms (6a) and (6b) and the inner ends of the arms (7a) and (7b), respectively, at a pair of positions that are symmetrical about an axis (L) that passes through the center of gravity of the reflective mirror, and a drive apparatus (D) for applying a drive force separately and independently to the oscillating elements (6) and (7), so as to move the inner ends of the arms (6a), (6b), (7a), and (7b) upward and downward separately and independently.

Abstract: A thin-film magnetic head is disclosed wherein a first core portion includes an insulative island of inorganic material. A first coil section is formed in the island so that it presents a flat common surface with the island and substrate. A gap-forming insulating layer is on the first coil section and the first core portion. A second core portion is on the gap-forming layer, forming a magnetic circuit with the first core portion. A second coil section is connected to the first coil section to form a coil therewith. In a modification, the head comprises a nonmagnetic substrate in which a coil section is formed to present a flat common surface. Metallic ferromagnetic material is used to form core portions on the coil section.

Abstract: A Hall effect magnetic head performs predetermined operations such as recording, reproducing and erasing of data on a recording medium which is capable of magnetically recording data therein. The magnetic head includes first and second magnetic members which define therebetween a front gap which faces the recording medium, a space in which a magnetic field developing means is disposed, and a rear gap in which a Hall element is disposed. The Hall element is applied with a bias magnetic field developed by the magnetic field developing means and by a signal magnetic field developed by the recording medium. The Hall element comprises a vertically magnetizable thin layer or film and is caused to output as a Hall voltage a signal contained in the signal magnetic field. The front and rear gaps are adequately dimensioned to increase the Hall voltage. The magnetic head may include second magnetic field developing means for preventing the bias magnetic field from influencing the recording medium.

Abstract: An electromagnetic pickup cartridge comprises a movably supported permanent magnet magnetized in the direction of the thickness thereof, a cantilever secured to the magnet with a stylus attached to the free end thereof, and a pair of magnetic flux sensors stationarily mounted above the permanent magnet at right angles to each other for sensing the angular displacement of the permanent magnet about different axes with respect to a neutral position.

Abstract: Moving coils of a phonograph pickup are made of a substance having magnetoresistance so that the electrical resistance of the coils are detected by means of bridge circuits. The amounts of resistance variation of the coils are used to produce a vertical component output signal and a horizontal component output signal which respectively indicate the vertical and horizontal displacements of the coils from its optimum operating point with respect to the magnetic field of the pickup. The vertical and horizontal component output signals are used to control vertical and horizontal control motors which correct the attitude of the tone arm so that the moving coils are accurately positioned at the optimum operating point irrespective of the warp and/or eccentricity of the phonograph disk.

Abstract: A moving-coil type stereo pickup cartridge comprises a vibration mechanism, including a stylus for tracing the groove of a sound track on a record disc, at least one coil plate provided in the vibration system and adapted to vibrate in response to vibrations of the stylus, and a structure for forming a magnetic field for the coil plate. The coil plate comprises a thin insulative substrate and a pair of left and right coils substantially symmetric with respect to a center line and formed by an electrically conductive thin film placed in a spirally wound pattern on at least one surface of the substrate. The magnetic field-forming construction comprises a permanent magnet and a pair of yokes adapted to clamp the permanent magnet. The pair of yokes have confronting surfaces for defining a gap in which the coil plate is interposed and a recessed substantially reverse V-shaped notch or cutout. The notch is defined by edge parts or facets.

Abstract: A moving-coil type pickup cartridge comprises a vibration system including a stylus for tracing a sound groove of a record disc, at least one coil plate adapted to vibrate in response to vibration of the stylus of the vibration system, and an arrangement for producing magnetic fields with respect to the coil plate. The coil plate has at least one coil formed by thin film in a spirally-shaped pattern. The magnetic field producing arrangement has at least one permanent magnet for producing magnetic fields wherein are produced magnetic fluxes of mutually opposite directions respectively in regions of the coil resulting from substantially halving of the coil in the vibration direction thereof.

Abstract: A moving-coil type pickup cartridge comprising a cantilever provided at the free end thereof with a stylus for tracing a sound groove of a record disc, a coil plate provided on the cantilever in a manner to vibrate in response to vibration of the stylus, and an arrangement for producing an effective magnetic field within a specific gap. The coil plate comprises a thin electrically insulating base plate and at least one coil which is formed from a thin film in a spirally-shaped pattern on at least one surface of the base plate. The coil plate has at least one upright part formed by bending the base plate together with a portion of the coil and interposed in a freely vibratory manner within said gap of the magnetic field producing arrangement and a mounting part integrally joined to the upright part and fixed to the cantilever.