Variable Resistance Patents (Class 369/152)
  • Patent number: 8358139
    Abstract: An optical reproducing apparatus connectable to optical pickups and a method of controlling an optical pickup thereof are provided. The optical reproducing apparatus measures resistance of an optical pickup on a port of a connection unit to which the optical pickup is connected, and determines the type of the optical pickup according to the measured resistance. Accordingly, optical reproducing apparatuses may be controlled according to the type of optical pickups, and manufactured using various optical pickups without checking the type of optical pickups, which allows convenient manufacturing of optical reproducing apparatuses.
    Type: Grant
    Filed: March 29, 2010
    Date of Patent: January 22, 2013
    Assignee: Samsung Electronics Co., Ltd.
    Inventors: Ji-seon Baek, Yukihiro Yamasaki
  • Patent number: 4429379
    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.
    Type: Grant
    Filed: October 8, 1981
    Date of Patent: January 31, 1984
    Assignee: Victor Company of Japan, Limited
    Inventors: Katsuhiko Oguri, Kazuhiro Sato