Scientists Reveal Olo: The New Colour You Can’t See With Your Eyes

A groundbreaking discovery from scientists in the United States has sent shockwaves through the scientific community: a new colour, invisible to the human eye, has been “seen” through the power of technology. Named olo, this colour is unlike anything humans have ever perceived naturally, pushing the boundaries of what we thought was possible in the realm of human vision.

The Discovery of Olo: A Step Into the Unknown

On April 18, 2025, professors from the University of California, Berkeley, and the University of Washington School of Medicine published an article in Science Advances, announcing the discovery of a colour that lies beyond the human visual spectrum. The colour, which they have named olo, was revealed using an innovative technique developed by the researchers.

The technique, dubbed Oz, uses laser pulses to stimulate the cones in the human eye, triggering a response that allows the viewer to experience the previously undetectable colour. This technology, named after the Wizard of Oz, is inspired by the fictional world where a simple pair of glasses could alter perception. Much like the trickery of the Wizard himself, Oz bends the rules of human sight.

Understanding the Technology Behind Oz

The Oz technology works by targeting individual photoreceptors in the eye with microscopic laser pulses. Developed by Austin Roorda, a professor at UC Berkeley, the device works by stimulating the M cones, the photoreceptors responsible for detecting green light. This stimulation, when performed in isolation, creates a colour that doesn’t exist naturally in the human visual field.

Ren Ng, a professor of electrical engineering and computer sciences at UC Berkeley, explained, “There’s no wavelength in the world that can stimulate only the M cone... I began wondering what it would look like if you could just stimulate all the M cone cells. Would it be like the greenest green you’ve ever seen?” This question led to the discovery of olo.

The Unique Experience of Olo

Five individuals have been fortunate enough to witness olo—four men and one woman, all with normal colour vision. These individuals, who participated in the groundbreaking study, describe olo as a deep, saturated shade of teal or green-blue.

Roorda himself, one of the co-authors of the study, described the experience of seeing olo as “like a profoundly saturated teal… the most saturated natural colour was just pale by comparison.” Other participants, like Hannah Doyle, a doctoral student at UC Berkeley, also described it as an intensely vibrant blue-green that is unlike anything they had seen before.

Interestingly, the closest comparison to olo is a teal square, though the olo-like square is still invisible to the naked eye. “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,” said Ren Ng. The technology required to visualize olo is so advanced that it’s not feasible with current consumer technology, but it offers tantalizing possibilities for the future.

Is Olo Really a New Colour?

From a scientific perspective, olo is not a new colour—it has always existed, it just happens to fall outside the human visual spectrum. However, as Francis Windram, a research associate at Imperial College London, explained, “From a sociolinguistic perspective, if people give new names to colours which previously were indistinguishable thanks to this technology, then maybe!”

The concept of naming colours and categorizing them is a matter of human perception. By giving a name to a colour we cannot traditionally see, we are altering the way we understand and interact with the world. It’s a reminder of the fluid nature of perception and language.

Could Olo Help People with Colour Blindness?

One of the most exciting possibilities of the Oz technology is its potential to assist individuals with colour blindness. For example, in cases like deuteranomaly, which causes reduced sensitivity to green light, this technology could be used to stimulate the appropriate cones in the eye to help restore proper colour perception. However, as Windram pointed out, the technology is still in its early stages, and much work needs to be done before it can be miniaturized for practical use.

Windram explained, “This would require a lot of work to miniaturize the technology, and is likely a long way off. Given that the laser must stably hit the correct cones in order to stimulate them, this may not really be feasible as a form of vision correction technologically.” It’s a promising avenue of research, but it remains to be seen how feasible it will be for widespread use.

The Future of Colour Perception

As we move forward into an era where technology is allowing us to perceive colours beyond our natural abilities, questions arise about how this will impact our understanding of the world. The human eye, which has evolved to perceive a specific range of colours, is being pushed to its limits. And with Oz technology, we are beginning to experience the visual world in ways we never thought possible.

Could we one day see olo in our everyday lives? Will future technologies allow us to experience more colours that lie beyond the reach of our natural perception? For now, olo serves as a fascinating glimpse into the future of human vision.

The discovery of olo also raises larger philosophical and societal questions about how we define colour and what it means to "see." Just as the dress debate in 2015 divided social media over the colour of a dress, this discovery could redefine our understanding of visual perception.

In the grand scheme of things, olo may not change the way we see the world, but it certainly opens the door to new possibilities. As scientists continue to push the boundaries of human perception, we may find ourselves seeing the world in ways we never imagined possible.