Scientists Uncover Never-Before-Seen Color, ‘Olo’, That Lives Outside Our Vision
Illustration 347472493 © Ai8075 | Dreamstime.com
Your color wheel might need an update. Researchers at the University of California, Berkeley, have just introduced a shade that defies the normal bounds of human perception and can’t even be replicated in nature.
‘Olo’, as this vivid blue-green hue is called, isn’t just rare, but it’s also impossible to encounter without the help of experimental laser technology that rewires how we see. The discovery hints at what might be hiding just outside humans’ visual range and offers a peek into the brain’s remarkable capacity to interpret new sensory signals.
The team’s breakthrough relies on a device called the Oz Vision System, which uses precise laser pulses to stimulate only the M cones—those sensitive to medium wavelengths, commonly associated with green. Typically, colors result from combinations of signals from three types of cones in the retina. But by isolating the M cones and avoiding the overlapping signals from the others, researchers created a new kind of neural input.
🔬Scientists have discovered a new color - "olo". It can't be shown on the 🖥screen, words can't describe it - it's not 🟩green, not 🟦blue, and not something in between. The color is so unusual that the brain doesn't understand where to place it. Only five people have managed to… pic.twitter.com/VBiXpzq9Tb
— Daniela Collins (@romans11732) April 20, 2025
The resulting sensation didn’t resemble any color previously recorded, prompting participants to describe it as entirely novel. That perception, dubbed “olo,” lies beyond the reach of digital displays and daylight alike.
To carry out the experiment, researchers mapped each participant’s retina using adaptive optics and optical coherence tomography. This allowed them to locate individual M cones and deliver targeted laser flashes to those specific cells.
The volunteers, five in total—including one of the researchers, Ren Ng—then described what they saw and used a color-adjustment tool to try replicating the experience. All of them needed to add white light to come close, underscoring that olo sits outside the boundaries of traditional color mixing models.
so a group of scientists discovered a new color named "olo" after conducting an experiment and this pic is the closest color match (although they say it's nothing in comparison to the actual color) pic.twitter.com/aPKLwNwoH9
— aisha (@aiishadow) April 19, 2025
“Subjects report that olo in our prototype system appears blue-green of unprecedented saturation, when viewed relative to a neutral gray background. Subjects find that they must desaturate olo by adding white light before they can achieve a color match with the closest monochromatic light, which lies on the boundary of the gamut, unequivocal proof that olo lies beyond the gamut,” the team explains in its research paper.
However, “the Abney effect [a shift in hue with saturation] opens the possibility that the hue of the wavelength at best match may not exactly represent the hue of the undiluted olo color,” the researchers elaborate. Subjects have said that the closest they can describe the hue are “teal,” “green,” “blue-greenish,” and “green, a little blue.”
SCIENTISTS HACK HUMAN RETINA, REVEAL BRAND NEW COLOR ‘OLO’
— Mario Nawfal (@MarioNawfal) April 19, 2025
Using a precise technique called Oz, Berkeley researchers isolated the retina’s M cones, forcing five volunteers to see a hue named ‘olo’, a blue‑green no earthly scene can match.
By mapping every photoreceptor and… pic.twitter.com/wUqjzolxFg
The name Oz is a nod to the green-tinted glasses from The Wizard of Oz, a story that similarly plays with the line between perception and reality. And while some outside experts argue that olo might just be an exceptionally saturated shade of green, the research team believes the experience is fundamentally distinct. They point to the unique way the brain processes such targeted inputs, something natural light can’t replicate, as evidence that olo represents more than just an optical curiosity.
There are no consumer gadgets on the horizon that will let you see olo on demand. The tech remains complex, and the experiments require specialized lab setups. However, the potential applications—from understanding how we process vision, to assisting those with colorblindness or designing next-generation visual interfaces—are enough to keep scientists looking ahead. We have yet to scratch the surface of how far our senses can stretch.
[via BBC, Scientific America, Popular Science, Live Science, IFLScience, cover illustration 347472493 © Ai8075 | Dreamstime.com]
