[16p-Z24-1~18] 12.3 Functional Materials and Novel Devices

▲ [16p-Z24-9] Wireless, stretchable contact lens sensors for intraocular pressure monitoring

〇Qi Zhang¹, Te Xiao¹, Taiki Takamatsu¹, Lunjie Hu¹, Takeo Miyake^1,2 (1.IPS, Waseda Univ., 2.JST-PRESTO)

Keywords:Intraocular pressure, Contact lens, Wireless power transfer

Intraocular pressure (IOP) is an important factor of diagnosing glaucoma clinically because glaucoma is one of the most important causes of blindness. The common way to measure IOP requires the wire connection between a sensor lens on an eye and a detector, which is not suitable for long term monitoring. Therefore, we develop a wireless, stretchable contact lens sensor for real-time IOP monitoring. The wireless sensor system is similar with our previous works, consisting of a stretchable antenna for monitoring IOP changes and a reader coil for converting IOP changes to electrical signals.A stretchable antenna with a horseshoe shape is designed to keep the connection between the antenna and soft, moist contact lenses even the lens was dried. The resonant frequency of the antenna lens was shifted by increasing IOP of pig eye ranging from 5 to 50 mmHg, so the contact lens with antenna can be used as wireless IOP sensors. To enhance the sensitivity of IOP sensors, we increased the number of turns of designed antenna. When we used a triple-turn antenna, the sensitivity was up to 45.5kHz/mmHg at the resonant frequency of around 1.39 GHz.