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:
Sep. 12, 1989
Filed:
Nov. 04, 1987
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
An optical disk comprising a disk-like body having two base plates made of synthetic resin and two recording layers formed on the base plates, respectively. The body is formed by bonding the base plates, with a spacer interposed therebetween, such that the recording layers face each other. The disk further comprises two centering members, each projecting from the surface of the center portion of one base plate. Each centering member is made of synthetic resin, and one magnetic member is mounted on the centering member. The centering member is inserted in a hole formed in the center portion of the body. The centering member has a center hole defining the center of rotation of the body, and also three projections formed in the surface thereof which faces away from the recording layer. The magnetic member has three engaging holes and is mounted on the centering member, with the projections of the centering member fitted in the engaging holes. Since the optical disk has magnetic members, one on each surface, it can be attracted to the turntable of a drive mechanism by means of the magnetic force exerted by the magnet fitted in the recess formed in the surface of the turntable.