Spectroscopy’s New Role in Document Security
Even in today’s digital world, some of our most valuable documents are still printed on paper. Banknotes, passports and professional licenses have high value and are at risk for counterfeiting, tampering and forgery. The security printing industry has responded to the challenge by developing a multitude of new anti-counterfeiting and protection techniques, many of which are based on incorporation of novel optical features enabled by spectroscopy.
sponsored by Ocean Optics
Introduction:
Inks and pigments with optically unique properties can provide quick visual verification of authenticity, and can be difficult to replicate. These range from iridescent or color-shifting inks containing tiny flakes of mica that cause a change in color with viewing angle to inks that are poorly read by the illumination sources in traditional scanners used for copying.
Fluorescent inks are often used to overlay documents with special words or images that appear only when illuminated by UV light or light of another specific wavelength. Fluorescent pigments may also appear as fibers incorporated into the paper itself.
Cicely Rathmell, M.Sc.
