Finnegan, Henderson, Farabow, Garrett, and Dunner
Movable body driving apparatus
 An optical head driving apparatus is constructed to move an optical head along the radius of an information storage medium which is rotating, to face the optical head to a predetermined position of the information storage medium where the optical head carries out a predetermined information process with respect to the information storage medium. The optical head driving apparatus comprises at least one circular bearing and at least one elliptic bearing. The bearings are disposed on opposite sides of a center of gravity of the optical head, respectively. A first guide shaft extends to pass through the circular bearing while a second guide shaft extends to pass through the elliptic bearing. The bearings and the first and second guide shafts constitute a guide means to movably support the optical head. The optical head driving apparatus further comprises an optical head moving means for controlling the movement of the optical head. A moving portion of the optical head moving means is connected to the optical head such that a center of gravity of the moving portion of the optical head moving means is positioned substantially under the first guide shaft. 
Kabushiki Kaisha Toshiba
G
G11B
inventional
Hiroshi
Yamashita