What is it?
Optical Variable Devices are visible security features that change depending on the viewing angle. Examples of changes are color shifts (Optical Variable Inks – OVI) and image swaps.
How do you detect it?
OVD detection is performed with the naked eye by changing the position of the device with respect to the observer and the light source. The user must be properly trained to draw a reliable conclusion.
How does it work?
OVD are iridescent or non-iridescent authentication features which exhibit different visual information, such as movement or color changes, depending on the viewing and/or lighting conditions.
What do we think about this technology?
OVDs has the same drawbacks as any other visible features in general: it requires expertise to differentiate genuine from counterfeited OVD, it is expensive to deploy, and its usage cannot be stopped when started on a product line. Moreover, there are myriad OVDs on the market, with each requiring a specific lighting and tilting procedure to make it visible, and counterfeiters also provide their own OVD versions. This technology adds substantial manufacturing cost, and replacing it with a Cryptoglyph® (or AlpVision Fingerprint® if the OVD is on the product) will provide both higher security and higher user-friendliness when inspected.
Field of application
Secure documents, banknotes, plastic cards, passports, identity cards, driving licenses, credit cards and cosmetics.