New Contacts Let You See Infrared Light—Even with Your Eyes Closed
Straight out of science fiction, these contact lenses convert infrared light into visible light that humans can see
People who tested a new type of designer contact lens could see flashing infrared signals from a light source.
Humans have a new way of seeing infrared light, without the need for clunky night-vision goggles. Researchers have made the first contact lenses to convey infrared vision — and the devices work even when people have their eyes closed.
If you’re enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.
Near-infrared light sits just outside the range of wavelengths that humans can normally detect. Some animals can sense infrared light, although probably not well enough to form images.
Night-vision goggles enable humans to see infrared radiation, but they are bulky and require a power source to work. The new lenses avoid these limitations while also offering richer, multi-coloured infrared images that night-vision goggles, which operate on a monochrome green scale, typically do not.
For these reasons, some critics don’t think the lenses will prove useful. “I cannot think of any application that would not be fundamentally simpler with infrared goggles,” says Glen Jeffery, a neuroscientist at University College London who specializes in eye health. “Evolution has avoided this for a good reason.”
Nevertheless, the authors think that their lenses can be further optimized and foresee several possible uses for the invention. For instance, wearers would be able to read anti-counterfeit marks that emit infrared wavelengths but are otherwise invisible to the human eye, says co-author Yuqian Ma, a neuroscientist at the USTC.
Li, who was not involved in the work, offers another possibility: the lenses might be worn by doctors conducting near-infrared fluorescence surgery, to directly detect and remove cancerous lesions “without relying on bulky traditional equipment”.
To create the contact lenses, the scientists built on previous research in which they gave mice infrared vision by injecting nanoparticles into the animals’ retinas. This time, they took a less invasive approach and added nanoparticles made of rare-earth metals including ytterbium and erbium to a soup of polymer building blocks to form the soft lenses, and then tested them for safety.
The main challenge, Ma says, was to pack enough nanoparticles into the lenses to convert sufficient infrared light into detectable visible light, while not otherwise altering the lenses’ optical properties, including their transparency.
Tests in mice showed that animals wearing the lenses tended to choose a dark box that was considered ‘safe’ over one lit up by infrared light, whereas mice without the lenses showed no preference for either box. Humans wearing the lenses could see flickering infrared light from an LED well enough to both pick up Morse code signals and sense which direction the signals were coming from. The lenses’ performance even improved when participants closed their eyes, because near-infrared light easily penetrates the eyelids, whereas visible light, which could have interfered with image formation, does so to a lesser degree.
“Witnessing people wearing contact lenses and successfully seeing infrared flashes was undoubtedly an exhilarating moment,” Ma says.
This article is reproduced with permission and was first published on May 22, 2025.
Elizabeth Gibney is a senior physics reporter for Nature magazine.
First published in 1869, Nature is the world’s leading multidisciplinary science journal. Nature publishes the finest peer-reviewed research that drives ground-breaking discovery, and is read by thought-leaders and decision-makers around the world.
Source: www.scientificamerican.com