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:
Apr. 28, 1998
Filed:
Feb. 24, 1997
Applicant:
Inventors:
Margaret Evans Best, San Jose, CA (US);
Hal Jervis Rosen, Los Gatos, CA (US);
Kurt Allan Rubin, Santa Clara, CA (US);
Timothy Carl Strand, San Jose, CA (US);
Assignee:
International Business Machines Corporation, Armonk, NY (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11B / ;
U.S. Cl.
CPC ...
3692751 ; 3692754 ; 4286 / ;
Abstract
A multiple data layer optical medium, such as an optical disk, has a plurality of substrates, each of which has a data surface. The laser light beam from the optical data recording system is maintained on the data tracks of the two spaced-apart data surfaces by the use of tracking marks contained on the data surfaces. One of the data surfaces includes recorded information that identifies the type of tracking marks present.