The new era of digital paper What if there was a way to invisibly encode data onto paper? An EU-developed printed antenna circuit with flexible thin-film chip makes it possible. Digital Economy © Sophie De Schepper Everything is slowly becoming digitised, even playing cards and product packaging. For some time, it has been possible to print radio antenna circuits onto cardboard, enabling an individual item to be scanned and tracked. Using conventional technologies, a metal oxide near-field communications (NFC) circuit would be printed on a plastic substrate, creating a three-layer (paper-plastic-paper) sandwich. However, this structure would be conspicuously thick when used on playing cards. Conventional silicon chips such as on credit cards would be even thicker, and also prohibitively expensive to produce. Thinner NFC antennas The EU-funded PING project has developed a better kind of NFC antenna. The project’s new NFC tags consist of a printed antenna with a flexible thin-film chip. The antenna is printed directly onto one of the paper layers, eliminating the third plastic inner layer. This guarantees the same look and feel as a normal playing card. The tags do not include batteries. Instead, the chip gets the necessary energy from the signal it receives from the device reader. The main application is contactless scanning and reading. “The most common example of an existing NFC application is a ski pass,” says Sophie De Schepper, PING project coordinator. “You walk up to the terminal and an NFC reader detects the presence of the NFC tag. The reader verifies it based on the dates coded onto the chip, and decides to let the skier pass through or not.” It is no longer necessary to place a wallet against a scanner. PING applications include casino- and other game-cards. In a casino, each card would be individually identified. As the dealer deals, dedicated readers in the table record each card, making cheating impossible. This method also eliminates the complicated network of hidden television cameras necessary to broadcast professional poker matches. The combination of NFC tags and scanners means that the computer system constantly updates and broadcasts the players’ hands for the benefit of TV viewers. A different use involves product packaging. Suppose a shopper with a food allergy is in a supermarket holding a certain food packet that includes a PING tag. The packet is scanned with a NFC-enabled smartphone. Then the phone’s screen flashes a red warning, advising not to buy the item. “The phone compares the tag information against medical data stored on the smartphone, and informs you that the product contains ingredients to which you are allergic,” explains De Schepper. A second gaming application concerns collectible cards. The project enriched the card-trading experience. Phone-scanning automatically updates an online collection for sharing or competing with others. Game changer The project’s technology is a game changer. PING NFC tags will cost less than half of a conventional NFC tag. Also, the fact that the tags are so thin (less than 25 μm) and flexible means that they can be included in almost anything, without having to redesign existing products. For this work, PING won the European Commission’s Innovation Product Award. The next phase for the project will involve upscaling the processes needed for full production capacity. So far, the marketplace has shown considerable interest. No doubt, embedded NFC chips will become common in future. Soon everything that needs to be tracked or individually identified may include one of PING’s printed tags. They could revolutionise document authentication. Keywords PING, NFC, NFC tag, printed antenna, flexible thin-film chip, product packaging, scanner, near-field communication
