A team of scientists has discovered a new colour that humans have never seen. Surprisingly, this colour doesn’t exist in the natural world. Researchers created it by using lasers to stimulate the eye in a completely new way.
Unseen Colour Created with Lasers
To begin with, the researchers directed laser pulses into people’s eyes. These pulses overstimulated a part of the retina, pushing it beyond its usual limits. As a result, a new colour appeared—one that isn’t found in the visible light spectrum.
Five participants witnessed this colour. They all described it as “blue-green,” although they agreed this label didn’t fully capture what they saw.
Experts Left Amazed by the Discovery
Ren Ng, an electrical engineer at the University of California, Berkeley, expressed his amazement.
“We predicted from the beginning that it would look like an unprecedented colour signal but we didn’t know what the brain would do with it. It was jaw-dropping. It’s incredibly saturated,” he said.
To give others a rough idea, the team shared an image of a turquoise square. However, they emphasized that it doesn’t compare to the real experience.
“There is no way to convey that colour in an article or on a monitor. The whole point is that this is not the colour we see, it’s just not. The colour we see is a version of it, but it absolutely pales by comparison with the experience of olo,” said Austin Roorda, a vision scientist on the team.
How Did They Make It Happen?
Under normal conditions, humans see colours through three types of cone cells in the retina. These are:
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L cones (respond to long wavelengths),
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M cones (respond to medium wavelengths), and
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S cones (respond to short wavelengths).
Usually, these cones work together when light enters the eye. However, natural light cannot target just one cone type by itself.
Therefore, the scientists developed a new method. First, they carefully mapped a small area of a person’s retina to find the exact location of the M cones. Then, they used a laser to deliver quick pulses of light to each cone, adjusting for any small movements of the eye. This technique allowed them to activate only the M cones, leaving the L and S cones untouched.
As a result, the brain saw a colour that doesn’t exist in the normal visual world. It was a completely new experience.
They Named the Colour “Olo”
Finally, the team gave the new colour a name—“olo.” The name is based on binary code: 010. This code reflects that only the M cones were activated (the “1” in the middle), while the L and S cones remained inactive (the “0”s).
In short, this discovery shows how much more the human eye might be capable of seeing—if we know how to unlock it.