Scientists Claim Discovery of 'New' Color Perceived through Laser Eye Experiment
TEHRAN (Tasnim) – A team of US researchers say they have induced the perception of a color never seen before by stimulating the human retina with laser pulses—though the claim is drawing skepticism from some experts.
After hundreds of thousands of years on Earth, humans might assume they’ve seen every possible color.
But scientists at the University of California, Berkeley, suggest otherwise, following an experiment they say unlocked a novel hue using precision lasers.
The research involved firing laser pulses directly into participants’ eyes, targeting individual photoreceptor cells in the retina.
By isolating stimulation to specific cone cells, the scientists believe they pushed the brain into perceiving a color that does not exist in the natural world.
“We predicted from the beginning that it would look like an unprecedented color signal but we didn’t know what the brain would do with it,” said Ren Ng, an electrical engineer at UC Berkeley.
“It was jaw-dropping. It’s incredibly saturated.”
The color has been named olo, derived from the binary code 010, indicating that only the medium-wavelength-sensitive (M) cones are activated—unlike natural light, which stimulates combinations of long (L), medium (M), and short (S) cones.
To provide a sense of the hue, researchers shared an image of a turquoise square, though they emphasized that true olo can only be experienced through the precise retinal laser technique.
“There is no way to convey that color in an article or on a monitor,” said Austin Roorda, a vision scientist on the project.
“The whole point is that this is not the color we see, it’s just not. The color we see is a version of it, but it absolutely pales by comparison with the experience of olo.”
In human vision, colors are perceived when light stimulates cones in the retina tuned to different wavelengths.
Red light primarily excites L cones, blue activates S cones, and green typically stimulates a blend, particularly M cones.
However, no natural light selectively stimulates only M cones—until now.
To achieve this, the team mapped small areas of the retina to identify the positions of M cones.
They then scanned the retina with a laser, adjusting for eye movement, and fired short pulses directly at these cells.
The effect, they report in Science Advances, is a vivid, moon-sized patch of color within the viewer’s field of vision—visible only under artificial conditions.
But not everyone is convinced.
“It is not a new color,” said John Barbur, a vision scientist at City St George’s, University of London.
“It’s a more saturated green that can only be produced in a subject with normal red-green chromatic mechanism when the only input comes from M cones.”
He added that the work had “limited value.”
Still, the research team is optimistic about broader implications.
The technology, dubbed Oz vision—a nod to the Emerald City from L. Frank Baum’s books—may help scientists explore fundamental questions about visual perception.
It could also inform research into color blindness and degenerative eye conditions such as retinitis pigmentosa.
As for whether the public will ever see olo for themselves?
“This is basic science,” said Ng.
“We’re not going to see olo on any smartphone displays or any TVs any time soon. And this is very, very far beyond VR headset technology.”
