The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 14, 1990
Filed:
Mar. 09, 1989
Akihiro Kasahara, Charlottesville, VA (US);
Akira Yamada, Yokohama, JP;
Katsutoshi Wada, Kawasaki, JP;
Hideo Yamasaki, Yokohama, JP;
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
An objective lens driving apparatus is provided which can restrain hysteresis phenomena in the relationship between semi-static displacements and forces in a focusing direction of the objective lens. The apparatus can also maintain the balance of force even when the objective lens is shifted in a focusing or tracking direction. Thus, the objective lens can be readily prevented from tilting. The apparatus also has a simplified configuration that can readily start up control operations in servomechanism. Thus, stable control characteristics of the apparatus can be achieved.