“Materials engineers led by Jon Kellar at the South Dakota School of Mines and Technology says their invention comprises a QR code made of nanoparticles that have been combined with blue and green fluorescent ink. The code is sprayed onto a surface — paper, plastic film, office tape, glass — using an aerosol jet printer. It remains invisible until the object is illuminated by a near-infrared laser. The nanoparticles absorb photons at a non-visible wavelength but emit them in a visible wavelength, a trick called upconversion that causes the QR code to pop up almost like magic and allow itself to be scanned.”
http://www.rawstory.com/rs/2012/09/11/new-nano-code-ups-the-fight-against-counterfeiters/
Related posts:
Ron Paul Gets Cut Off During Interview On Syria With Wolf Blitzer
Feds searching passenger cell phones at San Francisco airport
Sheriff's Deputy Pleads Guilty in DWI Crash
High Times Starts $300M Marijuana Industry Investment Fund
New York ‘cannibal’ cop watched death porn: wife
5,000 Chinese factory workers strike over Indian takeover of American firm
Let Us Go A-Wassell-ing
Trump in Line to Receive Top U.S. Intelligence Secrets
Bitcoin mania: A week as a crypto-currency miner
Talks underway to unionize Volkswagen’s U.S. plant
Government Now Tracking Millions of U.S. Cars
D.C. Speed cameras: Traffic enforcement or highway robbery?
Central banks becoming major investors in stock markets
Lawsuit claims Chicago Police strip-searched trio in public
Washington man arrested for online threat against Obama