As covered on the Daily Tech News Show on April 23rd 2025

News source: https://www.bbc.com/news/articles/clyq0n3em41o
Scientific article: DOI: 10.1126/sciadv.adu1052

Published last week in the journal of science advances. A team of scientists used lasers to stimulate the eye in a specific way that enabled five team members to view a color they claim no human has ever seen before.

T- How did they do it?

They use a technique that they named Oz, in which they optically stimulate individual cells in the eye’s retina that can sense light, called photoreceptors. They do this with multiple groups of these cells. Theoretically, this allows to display colors beyond the known gamut of human color vision. This is because in normal vision, any light coming into the human eye that stimulates an M cone cell (responsible for blue) must also stimulate the neighboring L and S cone cells (responsible for red and green respectively). However, Oz stimulation can target only M cones, which sends a color signal to the brain that would never occur in normal human vision.
Targeting M cones had been done before but only with one or two cells at a time, whereas the proposed method works over a larger area.

T- Since this IS a tech show, what tech did they use?

Absolutely, they used optics scanning light ophthalmoscopy (AOSLO). Simply put… LASERS. Here’s the nitty gritty: First, they image the retina of the subject to determine the type of 1,000 cone cells. Then, they target 100,000 laser microdoses per second at each cone cell. This is from a single monochromatic light. Folks, don’t try this at home. In doing such, they mapped the hues produced by the Oz technique by performing color matching experiments by the subjects – if you’ve ever played the hues & cues board game you know what I’m talking about. This confirmed they can display a range of known colors to the eye with this technique.

T – So, what is this new color?

They named it “olo”, inspired from the binary 010. Five of the co-authors of this paper took part in the experiment. They report that olo appeared blue-green and is of “unprecedented saturation”, meaning that they had to add more white to the color to get it to match with its closest monochromatic light.

T- Is this really a new color?

The real technological feat here is stimulating specific cone cells. Whether olo is really a new color is up for debate. That is because perceived brightness depends on an individual’s cone sensitivity. Other researchers are not convinced this counts as a new color and that the claim is rather sensationalized. We should also note that the only people who have seen olo so far are all authors of this publication.

T- Are there any future applications for olo?

Right now it seems impractical as a color to paint your room… The research team is investigating applications in color blind people, to potentially help distinguish between colors.