Korean researchers have developed the world’s first wireless contact lens equipped with an ultrathin OLED display to diagnose retinal conditions. This new lens could replace the need for large machines and dark rooms, making eye tests faster, more comfortable, and easier for patients.
The research team from the Korea Advanced Institute of Science & Technology (KAIST), working with ETRI and Seoul National University Bundang Hospital, has designed the contact lens to perform electroretinography, or ERG.
This is a special test that measures how the retina, the light-sensitive part of the eye, responds to light. Doctors use this test to find inherited retinal diseases or check if the retina’s function is getting worse over time.
Professor Seunghyup Yoo, who led the project, explained, “Integrating the flexibility and diffusive light characteristics of ultrathin OLEDs into a contact lens is a world-first attempt. 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.”
As ERG tests have been done in a very controlled and restrictive way. Patients sit in a dark room and look into a large device called a Ganzfeld, which sends flashes of light to the eye. The process can be uncomfortable and tiring, especially for children or elderly patients. “Patients have to stay still, keep their eyes open, and sit in the dark for the whole test. This is not easy for everyone,” Professor Yoo added.
The new OLED contact lens changes that experience completely. It has an ultrathin, flexible OLED display built into the lens itself, only 12.5 microns thick, around six to eight times thinner than a human hair.
The OLED spreads gentle, even light across the retina, avoiding the heat problems caused by traditional LEDs. The device is wireless and includes a tiny antenna and control chip, allowing it to send and receive signals without cables.
It also works with a small controller built into a sleep mask, which connects to a smartphone. This means patients could have the test in an open, bright clinic instead of an isolated dark room. “We wanted to make the test simple and comfortable so more people will be willing to do it,” said Yoo.
Most smart contact lenses today use inorganic LEDs, which give off light from one point and can cause heat build-up. This can be harmful to the eye and also limits the light’s strength. The OLED in the new lens is different because it emits “areal light” that spreads over a wider area, which is safer and more stable.
Animal testing proved that the OLED lens is safe for clinical use. It kept the eye’s surface temperature below 27°C, far lower than the level that could harm the cornea. It also continued working well in humid conditions, showing its reliability. “We tested it in different environments and it remained stable. This gives us confidence in its future use,” said Yoo.
The team believes this technology will make eye health checks much easier. Many retinal diseases, such as diabetic retinopathy, do not show clear symptoms until they have already caused serious damage. Quick and comfortable tests mean more people could get their eyes checked regularly, giving doctors a better chance to catch problems early and start treatment before vision is permanently lost.
The OLED contact lens could also open the door to more advanced uses. Researchers are already considering how it could help in myopia treatment, light-based brain therapy, and even augmented reality applications. Because the lens is so thin and comfortable, users can wear it without affecting their vision.
“This is not just a medical device,” Yoo said. “It is a small step toward the future of wearable healthcare. Soon, contact lenses like this might diagnose, monitor, and even treat eye conditions all while you go about your normal day.”
The invention has created excitement in the global medical technology community. Experts say it could be a turning point for how eye diseases are diagnosed, making tests faster, easier, and available in more places. Instead of traveling to special facilities with large, expensive machines, patients could one day have these tests done in local clinics, schools, or even at home.
