[image of digits]
Steganography - Ultraviolet

Dyes and inks which fluoresce under ultraviolet (black) light have always been used as security markings to guarantee the authenticity of documents. The following images are only suggestive of the range of applications which are in use today.

Questions? Comments? Please email me... nick.gessler(at)duke.edu


US $5, 10 & 20

5 Euro

10 Euro

20 Euro

20 Euro (detail)

Sweden 100 Kronor

Sweden 100 Kronor

Sweden 500 Kronor

Sweden 500 Kronor

Bank of England 5 Pounds

Bank of England 10 Pounds

Bank of England 20 Pounds

Credit Cards

American Express Personal

American Express Corporate



Drivers' Licenses

California Driver's License

California Driver's License (closeup)


US Blank Pages

Chinese Visa

Russian Visa