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.

Date of Patent:
Jan. 04, 2000

Filed:

Feb. 11, 1997
Applicant:
Inventors:

Yusuke Akama, Saitama-ken, JP;

Tomonari Ishikawa, Saitama-ken, JP;

Assignee:
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11B / ;
U.S. Cl.
CPC ...
369271 ;
Abstract

A compact disc (CD) has a first centering hole having a first radius and has annular projection rings on both sides of the CD. The center of the ring is coaxial with the center of the first centering hole. A radius of an outer periphery of each of the projection rings is smaller than a second radius of a second centering hole of a video disc.


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