A group of researchers in Japan has developed a new contact lens technology designed to enable high-sensitivity, real-time monitoring of intraocular pressure (IOP), a key factor in glaucoma management. Glaucoma is a leading cause of blindness, particularly for those unable to monitor their IOP daily due to limitations in current measurement devices, which are often not portable or capable of continuous monitoring.
The research team, led by Professor Takeo Miyake from the Graduate School of Information, Production and Systems at Waseda University, included Te Xiao, Hanzhe Zhang, Taiki Takamatsu, Assistant Professor Saman Azhari from Waseda University, and Professor Kazuhiro Kimura and Assistant Professor Atsushige Ashimori from Yamaguchi University. Their findings were published on January 13, 2026 in the journal npj Flexible Electronics.
The scientists developed a resistive sensor based on a thin film made from PEDOT:PSS/PVA—a combination of Poly(3,4-ethylenedioxythiophene), Poly(styrenesulfonate), and Polyvinyl alcohol. The sensor uses a multilayer structure to measure IOP effectively in real time. It is integrated with a 70 MHz double-loop gold antenna for precise and continuous data collection.
To enhance the device’s sensitivity for daily use by people requiring IOP management, the team incorporated parity-time-symmetric wireless technology. This approach increased sensitivity by 183 times compared to standard wireless sensing systems.
Testing involved both laboratory (in vitro) measurements using porcine eyes and live animal (in vivo) experiments with rabbits that had elevated eye pressure induced through microbead injection. Results showed that readings from the sensor lens strongly matched those obtained with commercial tonometers.
Professor Miyake commented on the development process: "It is generally very challenging to fabricate a device on a contact lens due to the size limitations while maintaining user comfort. To address these limitations, we used microfabrication to fabricate an IOP sensor that fits well on the contact lens while maintaining flexibility and user comfort. Moreover, the use of parity-time symmetry allows for much higher sensitivity in wireless detection, making this work a major step towards the future of daily, real-time ocular health monitoring devices."
He also emphasized potential impact: "Overall, our platform is promising for long-term, non-invasive IOP monitoring, thus making a significant contribution to the early diagnosis and treatment of glaucoma," concludes Professor Miyake.
