Compact multi-layer handset phone 13.56 MHz NFC antenna design by novel laser-induced thin-film antenna (LITA) technologies

This article presents a compact multi-layer handset phone 13.56 MHz NFC antenna design by novel LITA (Laser-Induced Integrated Thin-Film Antenna) technologies, which is jointly developed by ITRI and ACON in Taiwan. Through the proposed LITA technology, metal layouts of antennas can be formed on the internal surface of a smartwatch casing successfully with conformal, thin-film type, multi-layer and highly integrating characteristics. It is demonstrated that by designing a NFC antenna to become a two-layer overlapped coil structure by LITA technology, the required antenna layout area can be reduced about 40% compared to the co-planar NFC coil designs and also keep good inductive distance. The constructed antenna prototype integrated with a NFC reader chip (NXP NPC300) is analyzed and the read distance between the proposed antenna and type1 to type4 NFC tags classified by the NFC Forum are tasted and discussed in this paper.