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:
Jul. 16, 1996
Filed:
Aug. 29, 1995
Steven K Harbaugh, Castro Valley, CA (US);
Authentication Technologies, Inc., Dublin, CA (US);
Abstract
A security thread for documents such as currency and banknote paper comprises a plastic substrate coated with a plurality of discrete metallic patterns of electrically-conductive material, such as aluminum. The metallic patterns are arranged on the surface of the thread to indicate the particular denomination of the currency paper. The thread is typically embedded entirely with the currency paper. A first embodiment of a verification device determines the authenticity and denomination of the currency paper by counting the number of conductive metallic patterns on the thread and comparing the count to various count ranges. A second embodiment of the verification device scans the thread in a narrow-edge direction such that it simultaneously encounters all of the conductive thread segments. Capacitive coupling of an oscillator signal into one or more sensing pads result in an electrical signal having a distinct pattern. This signal is compared to a plurality of signals stored in memory that are indicative of valid thread denominations.