Fight against forgery gets boost from invisible nano barcode
invisible version of square modern barcodes using nanoparticles and fluorescent ink to help in the fight against counterfeiting. Blocks of black and white Quick Response (QR) codes are increasingly common in marketing and can hold a hundred times more information than traditional barcodes. Smartphones can scan them in printed adverts to navigate to company websites. Researchers have found out how to print them with inks that are only visible under laser light, giving them potential in the fight against fake banknotes and counterfeiting, which the OECD estimates costs the world economy more than $250 billion a year.