Humans cannot see in the dark because scientists say we are not a nocturnal species like owls and cats. Human eyes did not evolve to see in the dark but through scientific research it is now possible using contact lenses. Scientists from the University of Science and Technology of Hefei, China developed contact lenses that convert infrared light into light that the human eye can see.
In the initial stage of testing, 45 nanometer particles containing gold particles, sodium gadolinium fluoride, ytterbium and erbium ions were sprayed. The resulting layer converts infrared light with a lambda between 800 – 1600 nm into light that humans can see. Then the contact lenses were developed for humans and the most interesting thing is that human vision is better if the eyelids are closed.
The first disadvantage of these contact lenses is that they cause blurred vision but this can be solved by adding power to the lens. The second disadvantage is that they are still not as good as the night vision (NOD) systems that exist on the market today.
This research paper was published in the journal Cell.