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:
Oct. 31, 2006
Filed:
Aug. 16, 2001
Applicant:
Frank Puttkammer, Coswig, DE;
Inventor:
Frank Puttkammer, Coswig, DE;
Assignee:
WHD Electronische Prueftechnik, Dresden, DE;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01R 31/08 (2006.01); G06K 7/08 (2006.01);
U.S. Cl.
CPC ...
Abstract
The invention relates to a method of examining the authenticity of a document provided with an optico-diffractively effective element or hologram by subjecting the hologram to capacitive coupling of a voltage and deriving a signal representative of the voltage for comparison with a reference signal representative of a hologram of an authentic document. The method may be improved by providing, between individual segments of the hologram, additional security indicia providing a signal in response to being irradiated by electromagnetic radiation of a predetermined frequency.