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:
May. 27, 2008
Filed:
Aug. 01, 2003
Applicants:
Peter Franz, Pienzenau, DE;
Ruediger Schmidt, Munich, DE;
Inventors:
Peter Franz, Pienzenau, DE;
Ruediger Schmidt, Munich, DE;
Assignee:
Giesecke & Devrient GmbH, Munich, DE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G06K 19/00 (2006.01);
U.S. Cl.
CPC ...
Abstract
A halftone image original is converted into a line screen halftone image including regularly spaced-apart screen linesthat are modulated in their width y in accordance with the tonal value to be represented. According to the invention, width y of screen linesis modulated only on one side so that screen linesare flat on one side and width-modulated on one side. Various examples are stated for how this screen line modulation permits effective copy protection.