A team of scientists in the US is asserting they have experienced a colour never seen before, following an experiment that involved firing laser pulses into the eyes of participants to stimulate retina cells. The experiment aimed to push human visual perception beyond its natural limits.
The scientists describe the colour as blue-green, though they emphasize that this doesn’t fully capture the depth of the experience, reports The Guardian.
According to Ren Ng, an electrical engineer at the University of California, Berkeley, “We predicted from the beginning that it would look like an unprecedented colour signal but we didn’t know what the brain would do with it. It was jaw-dropping. It’s incredibly saturated.”
The researchers introduced the new colour, named "olo," by sharing a turquoise square image. However, they made it clear that olo can only be perceived through the laser manipulation of the retina, making it impossible to accurately convey through a monitor or in writing.
Vision scientist Austin Roorda commented, “There is no way to convey that colour in an article or on a monitor. The whole point is that this is not the colour we see, it’s just not. The colour we see is a version of it, but it absolutely pales by comparison with the experience of olo.”
Humans perceive colours when light stimulates the cones in the retina, which come in three types sensitive to long (L), medium (M), and short (S) wavelengths. Natural light activates a blend of these cones, resulting in different colours. However, there’s no natural light that solely stimulates the M cones.
The Berkeley team aimed to bypass this limitation by using a laser to stimulate the M cones, creating a colour experience beyond the natural range of human vision.
The result, which was published in Science Advances, is a patch of colour about twice the size of a full moon, representing a state that natural light cannot produce. The researchers named the colour “olo,” derived from the binary code "010," indicating that only the M cones are activated.
Not everyone is convinced, however. John Barbur, a vision scientist at City St George’s, University of London, dismissed the claim, suggesting that it’s not a new colour, but rather a more saturated version of green that can only occur when M cones are isolated. He considered the discovery to have “limited value.”
Despite the skepticism, the researchers believe their tool, called Oz Vision, could offer insights into basic science and potentially aid in studying conditions like colour blindness and retinitis pigmentosa.
However, Ng clarified, “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.”
Bd-pratidin English/ FNC
