The study, published in Science Advances, examined the vision of five participants, four male and one female, all of whom have normal colour vision, as well as three researchers.

The researchers stimulated the retina cells in participants' eyes by directing a laser beam into one eye with a contraption called Oz, which is a device with mirrors, lasers and other optical devices.

All participants then claimed to have seen a colour no human has seen before, a colour the scientists called 'olo'.

The colour is most closely compared to a bright blue-green colour.

Normal vision involves three cone cells in the retina, known as S (sensitive to blue), L (sensitive to red), and M (sensitive to green).

The laser only stimulated the M cone, which is what allowed the human eye to perceive a colour "that never occurs in natural vision," the study said.

University of California Professor Ren Ng told BBC Radio 4's Today program that the colour is "more saturated than any colour that you can see in the real world."

"Let's say you go around your whole life and you see only pink, baby pink, a pastel pink," he said.

"And then one day you go to the office and someone's wearing a shirt, and it's the most intense baby pink you've ever seen, and they say it's a new colour and we call it 'red.' "

Researchers say the study could benefit further research about colour blindness.