Cushman, Darby & Cushman
Optical head movable in a tracking direction
 An optical head for use with an optical disk has a unit packaging an optical path conversion device for converting a light beam path from substantially in parallel to the surface of a rotating optical disk into a direction substantially perpendicular to the surface of the optical disk, a lens system for focusing the light beam onto the recording surface of the optical disk, and a focus controlling mechanism for adjusting the focus of the lens system. A head outer shell supports the unit by one or more diaphragms for movement of the unit in the parallel direction of the optical path. A track control mechanism which includes an electromagnetic actuator adjusts the positional relation of the unit relative to outer shell in that parallel direction without causing unit movement in the perpendicular direction. 
Nippon Telegraph & Telephone Public Corporation
G G
G11B G11B
inventional inventional
Akinori Kikuji Hiroo Susumu
Watabe Kato Ukita Yonezawa