Researchers at the University of California, Berkeley, have discovered a way to trick the human eye into seeing a new, highly saturated blue-green color, which they’ve named “olo.” Inspired by ‘The Wonderful Wizard of Oz,’ the breakthrough was made possible by a technique called Oz, which precisely targets photoreceptors in the retina using tiny doses of laser light.
In Baum’s classic novel, Emerald City appears brilliantly green through tinted glasses. Similarly, the Oz technique manipulates human vision, but instead of creating an illusion, it unlocks an entirely new perception of color.
The research team, led by Austin Roorda, a professor of optometry, has developed a system that activates up to 1,000 photoreceptors simultaneously. By carefully controlling which cones in the retina receive laser pulses, they created the experience of olo, a shade more intense than any naturally occurring green.
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“We’ve created a system that can target photoreceptor cells with high precision, allowing us to explore fundamental questions about human color vision,” said James Carl Fong, a doctoral student and co-developer of Oz.
How Oz Works?
Humans perceive color through three types of retinal cone cells:
- S cones detect blue wavelengths
- M cones detect green wavelengths
- L cones detect red wavelengths
Due to overlapping sensitivity between M and L cones, no naturally occurring wavelength stimulates only the M cones. The Oz technique isolates these cones, effectively generating a never-before-seen color.
This was achieved through the use of advanced laser mapping of individual cone cells, enabling the precise activation of selected cones without interference. Using software developed by Fong, researchers manipulated color perception in five test subjects, including themselves, as a result, leading to a surprising “wow” moment.
The findings suggest profound applications beyond color perception. Oz technology could:
- Simulate vision loss for studying retinal disease
- Help color-blind individuals perceive missing hues
- Expand human sight to tetrachromatic vision, akin to some birds
Roorda is optimistic about the brain’s ability to interpret novel stimuli. “If you create new sensory inputs, the brain finds ways to make sense of them,” he said.
While the color olo may not occur in nature, this discovery challenges long-held assumptions about human vision, pushing the boundaries of what the human eye is capable of seeing.
An astonishing glimpse into the future of sight, Oz may be the next step toward reshaping how we see the world.
Journal Reference:
- James Fong, Hannah Doyle, Congli Wang et al. Novel color via stimulation of individual photoreceptors at the population scale. Science Advances. DOI: 10.1126/sciadv.adu1052
