22-05-2025
‘Night vision' contact lenses will allow people to see in the dark
Contact lenses that allow people to see in the dark have been invented by Chinese scientists.
The invention allows people to see infrared light, which is normally invisible to the human eye, and converts the wavelength so it can be detected.
Experiments on humans proved that wearers could reliably see flashing lights in the infrared light range, which is similar to the type of light emitted by TV remote controls.
Other experiments indicated that mice wearing the contact lenses demonstrated improved vision in the dark compared to their regular sight.
The technology uses the same principle as night vision goggles which capture infrared light – which is emitted by heat.
But unlike night vision goggles, the contact lenses do not require a power source. They work by converting the infrared light so that it can be seen by the wearer as either red, green or blue light.
Studies on mice found the contact lens, a standard off-the-shelf product fitted with a bespoke thin layer of infrared-slowing nanoparticles, was safe and viable before it was tested on humans.
Prof Tian Xue, the study author and a neuroscientist at the University of Science and Technology of China said: '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.'
The human tests also found that the gadget is almost four times more effective at spotting infrared light when a person closes their eyes because the eyelid helps shut out light that is visible to the human eye and reduces interference.
The inventors are now hoping to develop their product to help people with colour blindness as well as investigating the potential for night vision.
The prototype is only strong enough to detect bright bursts of infrared light and is not potent enough to pick up on weaker sources, such as body heat. But future work will try and make them more powerful, to allow for improved nocturnal sight.
Prof Xue said: 'Our research opens up the potential for non-invasive wearable devices to give people super-vision.
'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.
'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.'
The study is published in the journal Cell.
