“Anti-Copy Encrypted Pantograph”
U.S. Patent No. 6,692,030
A much improved anti-copy pantograph for security documents that is created by utilizing micro alphanumerical characters to create an encrypted message that cannot be digitally replicated and re-printed. What is replicated on a color copy is a robust copy/void warning message. To view and verify the encrypted nano characters, use a magnifying glass. Because of the encryption, this technology can be used to trace its origin and is also court enforceable.
The Mechanics of the Competition
Color copiers obviously were not designed to counterfeit documents. They simply do what the name implies, and that is to make a copy as close as possible to the original. Understanding this, they must optically look at an image and determine how to best naturally copy the original. They have the job of a scanner and printer in one machine and are not very good at mimicking large and small elements at high resolutions. There will always be some LOSS or GAIN in the “conversion to copy” process which they will automatically enhance. Sometimes elements that are so small actually become smaller (or drop out) in the process and images that are a little larger will gain or distort in size. In the past, your standard big dot – little dot worked well enough that the copier gained and lost imagery at a greater rate than the copiers today. So the VOID message that used to appear no longer does because of the resolution improvements in scanning and printing. Big dot – little dot is obsolete.
SAM – Screen Angle Modulation pantographs are still popular because they hide the latent message so well. Because they do not require large and small images in unison, only line angle changes, the end product is print that hides the VOID message extremely well. Understanding the scanner images the document in one lineal direction (optics pass across sheet in one direction) this technology realizes that the copier has a difficult time producing a 45 line the exact same as a 90 line. The difference once again is a little loss and gain which makes the latent message appear. The problem is that a simple switch to a photo setting on the newer color copiers will easily defeat this pantograph not to mention a digital counterfeiter that uses a high resolution scanner and printer. SAM technology is on the near verge of being obsolete.