Did you know that UV lamps are used in the process of printing currency and identifying counterfeit currency?
The Bureau of Engraving and Printing (BEP) prints billions of dollars every year! The BEP has several state of the art printing facilities in the US where offset lithography and plate printing are used to print US currency. With newer printed currency, UV lights show a fluorescent colored band on bills to show authenticity.
Fun Fact: All bills, regardless of denomination, utilize green ink on the backs. Faces, on the other hand, use black ink. A color-shifting ink is used in the lower right hand corner for the $10 denominations and higher. A metallic ink is used for the freedom icons on redesigned $10, $20, and $50 bills.