These Infrared Night-Vision Contacts Let You See Through Your Eyelids

Gizmodo

22-05-2025

Scientists want to give people super-vision. Literally.
In a move straight out of a sci-fi movie, scientists have created wearable infrared contact lenses that allow you to see in the dark, even with your eyes closed.
A group of scientists from the University of Science and Technology of China unveiled the lenses in a study published today in Cell.
Unlike infrared goggles, these contact lenses don't require a power source. Instead, they convert infrared light to visible light using nanoparticles. The ten lucky human participants who tried on these contact lenses could perceive otherwise imperceptible infrared wavelengths, according to the study.
The scientists are already thinking about futuristic applications of the contact lenses. 'Our research opens up the potential for non-invasive wearable devices to give people super-vision,' said Tian Xue, a neuroscientist at the University of Science and Technology of China and the senior author of the study in a statement to Cell Press. 'There are many potential applications right away for this material. For example, flickering infrared light could be used to transmit information in security, rescue, encryption or anti-counterfeiting settings.'
The contact lenses use upconverting nanoparticles—teeny tiny particles that absorb multiple low energy photons and emit a single, high-energy photon. Specifically, these particles absorb lower-energy near-infrared wavelengths (800-1600 nm range) and convert it to wavelengths that are visible to mammalian eyes (400–700 nm range). The researchers had already demonstrated that they could enable infrared vision in mice by injecting particles into the retina, but they wanted to develop a method that didn't require you to inject anything directly into your eyeballs.
So, the researchers combined the nanoparticles with polymers that are used in normal soft contact lenses.
The scientists first tested a much smaller version of these contacts on mice, finding that the mice behaved as if they could see infrared wavelengths. Taking advantage of the fact that mice prefer to hide in dark crevices, the researchers gave the mice a choice between a dark box or a box illuminated with infrared light. Without the contacts, mice showed no preference between the dark box and the illuminated box. But with the contacts, the mice were more likely to choose the dark box.
The researchers then recruited human participants to try out the lenses. The scientists found that people wearing the lenses could detect morse code-like flashes and perceive the direction of incoming infrared light from an LED. 'It's totally clear cut: without the contact lenses, the subject cannot see anything, but when they put them on, they can clearly see the flickering of the infrared light,' Xue said in a statement. 'We also found that when the subject closes their eyes, they're even better able to receive this flickering information, because near-infrared light penetrates the eyelid more effectively than visible light, so there is less interference from visible light.' They also saw this light better with their eyes closed.
The researchers also modified the contact lenses to allow participants to distinguish between different wavelengths of infrared light. They made a version of the lenses that convert different spectra of infrared light to specific visual wavelengths—980 nm was converted to blue light, 808 to red light, and so on.
But before you get too excited, though, it's important to note that participants wearing the lenses couldn't see all that well. They weren't able to make out fine details of their environment, for example, and could only see infrared light coming from an LED. This is because the contact lenses scatter the incoming infrared light, the authors wrote.
To combat this, the researchers created wearable eyeglasses using the same basic principles. This helped a little bit, and participants were able to distinguish infrared patterns and shapes, but still weren't able to see ambient infrared light.
The technology isn't quite at super-vision levels yet, and scientists are working on making these contacts more sensitive. 'In the future, by working together with materials scientists and optical experts, we hope to make a contact lens with more precise spatial resolution and higher sensitivity,' Xue said in a statement.