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:
Aug. 13, 1996
Filed:
Sep. 09, 1994
Ronald S Indeck, Olivette, MO (US);
Marcel W Muller, St. Louis, MO (US);
George Lawrence Engel, St. Louis, MO (US);
Alan L Hege, St. Louis, MO (US);
Washington University, St. Louis, MO (US);
Abstract
A method and apparatus is disclosed for determining the remanent noise in a magnetic medium by, for example, DC saturation of a region thereof and measurement of the remaining DC magnetization. A conventional magnetic recording transducer may be used to determine the remanent noise. Upon determination, the remanent noise may then be digitized and recorded on the same magnetic medium to thereby 'fingerprint' the magnetic medium. This 'fingerprint' may then be later used to verify and authenticate the magnetic medium as being an original. The magnetic medium may be of a type adapted to record information magnetically or, even more broadly, any magnetic surface or substance that can be sensed through its magnetic field. In such manner, any magnetic medium, or any object having an associated magnetic medium, may be 'fingerprinted' including credit cards, computer program diskettes, magneto-optic discs, videotapes, cassette tapes, bank checks, stock certificates, etc.