In April, researchers announced that they developed a device that allows people to see vibrant green and blue colors previously unseen by humans. Following this revelation, numerous requests poured in from the public eager to experience these colors firsthand.

This device could potentially enable individuals with certain types of color blindness to experience typical vision, while also giving those with normal vision an opportunity to perceive a broader spectrum of colors. “Our aim is to enhance the color experience,” states Austin Rolda from the University of Waterloo in Canada.

The retina at the rear of most individuals’ eyes contains three types of cone cells identified as S, M, and L. Each of these cones detects different wavelength ranges of light, aiding the brain in forming color perceptions based on signals received from them.

The M cone cells’ sensitivity range overlaps with the other two types, meaning they typically receive combined signals from multiple cone types.

Roorda and his team employed a highly accurate laser to selectively target about 300 M cones in a small area of the retina, roughly the size of a fingernail when held at arm’s length.

When five team members tested the device, they encountered a vivid blue-green hue that exceeded anything they had seen so far, which they named “olo.” This discovery was validated through a color matching experiment that compared olo to the complete visible light spectrum.

“It was truly an incredible experience,” remarks Roorda, who has witnessed olo more frequently than anyone else due to his essential role in developing the system. “The most vibrant natural light appeared dull in comparison.”

After their findings attracted media attention, the team received numerous inquiries from various individuals, including artists, interested in seeing olo. However, Roorda explained that they were unable to fulfill these requests, as setting up the device for a new person requires several days.

Instead, they are concentrating on two ongoing experiments. The first experiment aims to determine whether the device can temporarily enable individuals with color blindness to experience typical vision. Certain color blindness types arise from having only two cone types rather than the typical three. “We manipulate the signaling from specific cones within a type to simulate the existence of a third cone type,” Roorda explains. The objective is for people’s brains to interpret these signals as colors they have never experienced before.

The researchers are also exploring whether a similar technique could allow individuals with three cone types to perceive the world as if they had four cone types, potentially expanding their color perception. Results from both studies are anticipated to be available next year, Roorda indicated.