Counterfeiting Holograms
More research for Twenties:
Foiling counterfeiters
John Wallace, Senior Editor
Take any major credit card, hold it in the light, and tip it back and forth. There, on a patch of metallized plastic, a small image will shimmer and float, its eye-catching presence the salesclerk`s assurance--as well as the cardholder`s--that the card is not a fake. Similar holograms, durable and cheaply produced, are being used in increasing numbers throughout the world for security purposes, all based on the premise that holograms are hard to counterfeit. They are found on everything from whiskey bottles to ID cards, from concert tickets to price tags, from textile labels to government documents to money. Of all the security features added to credit cards over the years, holograms are what have best withstood the wiles of tamperers and forgers. But do they guarantee authenticity?
No, according to Steven McGrew, president of New Light Industries Ltd. (Spokane, WA), a company developing hologram anticounterfeiting technology. Although even the most-sophisticated hologram can be reproduced given enough time, money, and effort, the standard mass-produced hologram is, he says, rather easy to counterfeit. He reports that the Secret Service presented [at Holo-pakHolo-print 97, a conference on holographic security held in November 1997 in Orlando, FL] actual counterfeits of the dove found on the VISA card. "Most of them were bad, but some were very good, enough to fool some holographers," he says, adding that the better ones would easily fool any salesclerk.
The credit-card hologram is considered an optical variable device (OVD), a class of devices used for security and authentication that include gratings, conventional image-based holograms, and stereograms (which, as the observation point is shifted, can show action in the manner of a movie). At its simplest, an OVD is no more than a grating that gives rise to a colorful patch of light. In a more complex form, it may be made up of hundreds of two-dimensional computer-generated images, each viewable from a slightly different angle, the sum of which depicts a three-dimensional object created entirely in software.
Most mass-produced holograms are embossed on plastic, then back-coated with a reflective metallic layer (see Fig. 1, p. S23). Small embossed holograms can be produced for no more than a fraction of a cent each.
There is one characteristic that all OVDs share: they cannot be duplicated using conventional printing technology. The ubiquitous ink-jet printer, capable of counterfeiting currency and checks, is useless to the potential counterfeiter of OVDs. But although the equipment needed to forge an OVD is not offered at local computer stores, someone with enough knowledge and persistence can put together a setup good enough to be in business.
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