Out of those fortunate enough to witness the color, three were part of the research team behind the discovery, and the other two were colleagues from the University of Washington, based in Seattle.
To make this color visible to the human eye, a specialized process had to be developed. This involved creating a unique ‘technicolor technique’. As for why a laser nicknamed ‘Oz’ was necessary to make the color visible, we need to take a moment to understand the biology behind how we see color in the first place.
Our brains then take the signals from these three types of cones and mix them together, creating the full, vivid range of colors we experience in everyday life.
But here’s the thing—these cone types don’t operate in isolation. Their sensitivity ranges overlap with each other. So when a certain wavelength activates the M cones, it usually ends up stimulating the S or L cones too, depending on the exact wavelength involved.
“The name comes from the Wizard of Oz, where there’s a journey to the Emerald City, where things look the most dazzling green you’ve ever seen,” Ng shared with the publication.
Ng is actually one of the rare five people who have seen this newly identified color. It’s been given the name ‘olo’, and he described it as a striking ‘blue-green with unprecedented saturation’. The closest known color we have to compare it with is teal, though even that doesn’t quite match its intensity.
“Theoretically, novel colors are possible through bypassing the constraints set by the cone spectral sensitivities and activating M cone cells exclusively. In practice, we confirm a partial expansion of color-space toward that theoretical ideal.”
“Attempting to activate M cones exclusively is shown to elicit a color beyond the natural human gamut, formally measured with color matching by human subjects. They describe the color as blue-green of unprecedented saturation.”
“These results are proof-of-principle for programmable control over individual photoreceptors at population scale.”