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:
Dec. 27, 1988
Filed:
Dec. 29, 1987
Hans-Erdmann Korth, Stuttgart, DE;
International Business Machines Corporation, Armonk, NY (US);
Abstract
A rotary access arm, e.g. for an optical disk has crossed voice coil actuators (6a,b) for in-plane and vertical movements, e.g. track and focus control; the actuators are secured to its distal end in close proximity to the focussing optical system (5a,b). The heavy elements like laser light source (8) and beam analyzer (11) are arranged near the rotational axis (10) of the arm (or are completely separated therefrom) allowing a very lightweight construction. In an optical storage system using stacked disks coaxial access arms with individual position control are provided. For increased reliability of operation each access arm has two focussing optical systems at its distal end, viewing in opposite directions, and a bistable optical switch (12) to selectively focus the laser beam on one of the two adjacent optical disks. The focussing optical system can be realized with individual lenses or with two conjugate plano-aspheric lenses bonded to a 90.degree. reflection prism.