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:
Jan. 04, 2000
Filed:
Jul. 30, 1997
Philip E Rollhaus, Chicago, IL (US);
John R Powell, Arlington, MA (US);
Eric J Carlson, Sudbury, MA (US);
Daniel J Ehntholt, Hudson, MA (US);
Irwin C Winkler, Arlington, MA (US);
Christopher J Marmo, Nashua, NH (US);
James R Valentine, Reading, MA (US);
SpectraDisc Corporation, Providence, RI (US);
Abstract
An optical disc having machine-readable, information-encoding features is provided with a barrier layer secured to the disc. This barrier layer is configured to prevent machine-reading of the features. A reading-inhibit agent, included in the disc and activated by removal of the barrier layer, is operative, once activated, to alter the disc to inhibit reading of the disc. Alternately, the barrier layer can be eliminated, and the reading-inhibit agent can be activated by initial reading of the disc, as for example by exposure to optical radiation associated with reading of the disc, or rotation of the disc.