Researchers at Korea Advanced Institute of Science and Technology (KAIST) in South Korea have developed a wireless OLED contact lens which can monitor ocular biomarkers. The experimental research, published in ACS Nano, presents a new way to non-invasively perform electroretinography (ERG).
the researchers were able to incorporate a flexible ultrathin OLED (about 12.5 μm, 6–8 times thinner than a human hair) into a contact lens - it also sports a wireless power-receiving antenna and a control chip.
The device uses ERG, a diagnostic method which measures the electrical activity of the retina in response to a light stimulus. ERG is an essential tool for the evaluation of retina health and the diagnosis of acquired and inherited eye diseases like retinitis pigmentosa, Stargardt disease, and certain cancers.
The new tool could dramatically simplify the diagnostic process compared to conventional methods which require a dark room, large specialised light sources, and long continuous periods of the patient remaining still and unblinking.
Principle investigator on the project, Seunghyup Yoo said: “Integrating the flexibility and diffusive light characteristics of ultrathin OLEDs into a contact lens is a world-first attempt.”
He continued: “this research can help expand smart contact lens technology into on-eye optical diagnostic and phototherapeutic platforms, contributing to the advancement of digital healthcare technology.”
The safety and efficacy of the contact lens was tested on rabbits. Experiments showed that the rabbits’ eye surface temperature remained below 27°C, a comfortable threshold for the risk of corneal heat damage. Furthermore, the performance of the OLED was maintained even in humid environments. The team think that these data suggest the lens could be an effective clinical diagnostic tool.
The applications for this device span many fields such as myopia treatment, ocular biosignal analysis, light-based neurostimulation, and even augmented reality.