Conformai integrated multi-layer thin-film antenna by novel LITA technologies for smartwatch wearable device applications

This article presents a conformai integrated multi-layer thin-film antenna design implemented by novel LITA (Laser-Induced Integrated Thin-Film Antenna) technologies for smartwatch device applications. Through the proposed LITA technology which is jointly developed by ITRI and ACON in Taiwan, metal layouts of antennas can be formed on the internal surface of a smartwatch casing successfully with conform al, thin-film type, multi-layer and highly integrating characteristics. It is demonstrated that by designing a compact two-layer thin-film feeding capacitor by LITA, a much smaller PIFA antenna size (5×10 mm
²
only) can be achieved successfully compared to the PIFA with a co-planar capacitive feeding structure and the prior PIFA with a direct feed. The constructed antenna prototype analyzed with presence of a user's right hand is discussed in this paper.