Chinese researchers have developed innovative contact lenses that enable humans to perceive near-infrared (NIR) light—normally invisible to the naked eye—even with their eyes closed. This groundbreaking technology, detailed in the journal Cell, operates without any external power source, marking a significant advancement in wearable vision enhancement.
How the Technology Works
The lenses are crafted from a flexible, transparent polymer commonly used in standard contact lenses. Embedded within are upconversion nanoparticles that absorb NIR light and re-emit it as visible red, green, or blue light. This conversion allows the human eye to detect infrared signals without the need for bulky equipment or batteries.
Remarkably, these lenses function even when the eyes are closed. This is because NIR light penetrates the eyelids more effectively than visible light, enhancing the perception of infrared signals in such conditions
Testing and Observations
Initial experiments involved fitting mice with the infrared-sensitive lenses. The rodents exhibited behavioral changes, such as avoiding areas illuminated with infrared light, indicating their newfound ability to perceive it. Subsequent human trials demonstrated that participants could detect flickering infrared signals and discern their direction, especially when their eyes were closed.
Potential Applications
These infrared contact lenses could revolutionize night vision, assist the colorblind, and enhance visibility in fog or dust. They may also aid rescue and security missions by detecting hidden heat signals—all without needing a power source.
Future Enhancements
While the current lenses effectively detect NIR light, image resolution remains limited due to their proximity to the retina. To address this, researchers are developing supplemental glasses that utilize the same technology to provide clearer visuals. Additionally, efforts are underway to refine the nanoparticles for improved sensitivity and spatial resolution .
