Patents Examined by Shami, Khaled
  • Interferometric rotating condition detection apparatus
    Patent number: 4967072
    Abstract: A rotating condition detection apparatus includes a light source for illuminating a radial lattice having a plurality of lattice patterns marked on a periphery of a rotating body at an equi-angle; an optical unit for superimposing two refraction lights having a predetermined number of order reflected in two predetermined directions by the radial lattice; a photosensing device for sensing the superimposed light; and a detector for detecting a rotating condition of the rotating body in accordance with the output of the photosensing means.
    Type: Grant
    Filed: February 20, 1990
    Date of Patent: October 30, 1990
    Assignee: Canon Kabushiki Kaisha
    Inventor: Tetsuharu Nishimura