Sharp Japan has developed a transparent NFC antenna that can be built right into a device's display. This solution can enable payments and authentication by simply holding an NFC-compatible smartphone or IC-card over the screen.
As the NFC antenna is transparent, it can be integrated into the display transforming the entire display's surface into an active region. Fabricated with finely screen-printed silver lines by applying "metal mesh technology" typically used for touch panels, multiple NFC antennas with a light transmittance at 80% cover the entire display panel which is 42 inches diagonally. Compared to traditional RFID tags which require touching or swiping a card onto the tag, here the large area antenna design increases the operational distance up to 3.5cm, with response times of under a second. Although Sharp does not expect the transparent antenna to be used in small displays, it can be integrated in to devices with small screens like smartphone displays.
The multiple invisibly integrated NFC antennas spread across a large-size display effectively divides the screen into multiple NFC-capable areas that are time multiplexed so as to identify which part of the screen is being used for NFC communication, doubling as a coarse touch panel.
This means users don't have to tap their NFC reader only to a dedicated part of the screen, and instead could tap directly on a catalog item they would want to purchase online, enabling a more intuitive user experience. Other use cases would be for shoppers to directly access NFC-labelled product information on the shop's premises, using available information on displays.
Applications of this transparent NFC antenna include billing at POS terminals and vending machines, individual authentication in business, educational, medical, amusement, etc. facilities.
Sharp Japan is planning to begin mass production of the transparent NFC antenna in the 2019 fiscal year, with commercialization expected in the following year.
