Device for displacing the reading head of a video disc in radial and vertical directions
Two dimensional actuator for moving optical medium of scanning device
Optical data storage and readout apparatus and head, using optical fibers between stationary and movable units Patent #: 4771415
ApplicationNo. 286723 filed on 12/19/1988
US Classes:369/44.14Optical head servo system structure
ExaminersPrimary: Richardson, Robert L.
Attorney, Agent or Firm
Foreign Patent References
International ClassG11B 007/12
Foreign Application Priority Data1987-12-23 JP
AbstractAn optical head assembly for use with an optical disk apparatus includes a magnetic circuit block having permanent magnets each being elongate in a track traversing direction and a yoke for forming a magnetic circuit which conducts a magnetic field generated by the permanent magnets. The yoke includes a first through hole extending in a focusing direction, magnetic gaps located at opposite sides of the first through hole in the track traversing direction and individually accommodating the permanent magnets, and a second through hole for admitting the light beam issuing in the track traversing direction to guide it to the first through hole. The first through hole and magnetic gaps each has a cross-section relatively long in the track traversing direction. A beam deflector is loosely fitted in the first through hole for deflecting in the focusing direction the light beam which is incident thereto from the second through hole. The beam deflector is supported by a carriage. An objective lens focuses the light beam deflected by the beam deflector in the focusing direction onto the recording medium surface. The objective lens is mounted on a lens holder which is in turn mounted on the carriage movably in the focusing direction. Guide members support the magnetic circuit block and carriage movably in the track traversing direction along the recording medium surface.