Contact Lenses Developed By Scientists Allow Humans To See Near-Infrared Light

Chinese scientists, leading an international team, have created innovative contact lenses that enable humans to perceive near-infrared light. This development could significantly impact medical imaging and visual assistance technologies. The study, published in the journal Cell, merges visual neuroscience with rare earth elements to produce transparent lenses that convert invisible infrared light into visible images.

The human eye typically perceives light with wavelengths ranging from 400 to 700 nanometres. However, near-infrared light spans from 700 to 2,500 nanometres and can penetrate biological tissues effectively with minimal radiation damage. Researchers from the University of Science and Technology of China, Fudan University, and the University of Massachusetts Medical School engineered rare earth elements to transform three distinct infrared wavelengths into visible red, green, and blue light.

Previously, the team developed a nanomaterial that allowed mammals to naturally see near-infrared light when injected into their retinas. Recognising that retinal injections are not feasible for humans, they shifted focus to designing a wearable alternative using soft contact lenses. By modifying the surface of rare earth nanoparticles, they dispersed them in polymer solutions to create highly transparent contact lenses.

Volunteers wearing these lenses could identify infrared patterns and temporal codes. They could even distinguish three different "colours" of infrared light. This essentially broadens the human visual spectrum beyond its natural limits. Unlike night vision goggles, these lenses do not require a power source and offer a more natural visual experience in low-visibility conditions like fog or dust.

This non-invasive technology holds promise for various applications such as medical imaging, information security, rescue operations, and treating colour blindness. Although still in the proof-of-concept phase, researchers believe it could eventually aid those with visual impairments and change how humans interact with invisible light spectrums.

The team’s innovation represents a significant step forward in enhancing human vision capabilities without invasive procedures. As research progresses, these contact lenses might become a practical tool for improving vision in challenging environments.

With inputs from WAM