Researchers from the University of Science and Technology in Hefei, China, have created the unique item can only detect infrared radiation from an LED light.

But the team is working to improve the sensitivity of the nanoparticles, which absorb the invisible light from the infrared radiation and turn it into visible wavelengths.

This is so the contact lenses can find lower levels of infrared light that is invisible to human eyes.

The scientists combined the nanoparticles with flexible and non-toxic polymers that are used in ordinary contact lenses - thin lenses placed on the eyes so people can see clearly - and the results showed people could clearly spot infrared signals in darkness.

Writing in the journal Cell, the team said: "Light plays a particularly essential role in conveying a significant amount of external information for living organisms to comprehend the world.

"However, mammals can only perceive a small fraction of the electromagnetic spectrum as visible light.

"This means that over half of the solar radiation energy, existing as infrared light, remains imperceptible to mammals.

"Here, we report wearable near-infrared upconversion contact lenses with suitable optical properties…flexibility and biocompatibility.

"Humans wearing [the contact lenses] could accurately detect near-infrared temporal information like Morse code and discriminate near-infrared pattern images.

"Interestingly, humans with [the contact lenses] exhibited better discrimination of near-infrared light compared with visible light when their eyes were closed."