Title:
磁気媒体の真偽識別方法および装置
Document Type and Number:
Japanese Patent JP4076561
Kind Code:
B2
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.
Inventors:
Indec Ronald S
Muller mercer wet wet stain
Engel George Lawrence
Hezi Alan Lee
Muller mercer wet wet stain
Engel George Lawrence
Hezi Alan Lee
Application Number:
JP2006158380A
Publication Date:
April 16, 2008
Filing Date:
June 07, 2006
Export Citation:
Assignee:
Washington University
International Classes:
B42D15/10; G11B5/02; G06F21/00; G06K1/12; G06K17/00; G06K19/06; G06K19/12; G07D7/04; G07F7/08; G07F7/12; G09C1/00; G11B5/00; G11B20/00; G11B23/28; H04L9/32; G06F1/00
Domestic Patent References:
| JP63129520A | ||||
| JP57500851A | ||||
| JP2246050A |
Other References:
Hoinville et al.,Spatial Noise Phenomena of Longitudinal Magnetic Recoding Media,IEEE Transactions on Magnetics,米国,1992年11月,Vol.28, No.6,pp.3398-3406
Attorney, Agent or Firm:
Hiroo Suzuki