DoubleTake™ Personalization System
Protection Against Scanning and Copying - Induced Moiré
The first level of defence is derived from the grid-like nature of the DoubleTake™ character forms. The frequency of the lines used to make up the characters is tuned to create interference patterns on any digital scanner, including those used by colour copiers. The blotches evident in Figure 5 illustrate the interference effect known as Induced Moiré. It occurs because we have intentionally engineered our fonts to misalign slightly with the light-sensing elements a digital scanner uses to acquire image data. That means the scanning elements cyclically pick up differing amounts of picture data as the characters phase in and out of alignment. It doesn't matter how high the optical resolution of the scanner goes, some degree of interference pattern is unavoidable. The fundamental principle is that if you can't make a decent scan, you can't produce a passable counterfeit.
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| Figure 5 - Digital Scan Shows Induced Moiré |
Other security features:
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