An international team led by Chinese scientists has developed revolutionary contact lenses that enable humans to see near-infrared light — a breakthrough that could transform medical imaging and visual assistance technologies.
The study, published in the journal Cell on Thursday, merges visual neuroscience with rare earth elements to create transparent, wearable lenses capable of converting invisible infrared light into visible images, Xinhua news agency reported.
The human eye can typically detect light with wavelengths between 400 and 700 nanometres, missing a significant portion of the light spectrum present in nature.
Near-infrared light, which spans wavelengths from 700 to 2,500 nanometres, excels at penetrating biological tissue with minimal radiation damage, making it ideal for medical and technological applications.
Researchers from the University of Science and Technology of China, Fudan University, and the University of Massachusetts Medical School (USA) engineered rare earth elements that can convert three different infrared wavelengths into red, green, and blue visible light.
Previously, the same team developed a nanomaterial that, when injected into animal retinas, enabled mammals to perceive near-infrared light. However, since retinal injections are not practical for humans, the team shifted focus to designing a wearable, non-invasive alternative using soft contact lenses.
By modifying the surface of rare earth nanoparticles, the team enabled their dispersion in polymer solutions, ultimately fabricating highly transparent contact lenses, according to the study.
Human volunteers wearing the lenses could identify infrared patterns, recognize temporal codes, and even distinguish three different “colours” of infrared light — effectively expanding the human visual spectrum beyond its natural limits.
The non-invasive technology holds potential for a range of applications, including medical imaging, information security, rescue operations, and treating colour blindness.
Unlike bulky night vision goggles, these lenses enhance vision in low-visibility conditions such as fog or dust without requiring any external power source, providing a more natural visual experience.
While the technology remains at the proof-of-concept stage, researchers believe it could one day assist individuals with visual impairments and revolutionize how humans interact with the invisible light spectrum.-IANS
