Color-blindness, also known as color vision deficiency or CVD, affects approximately 1 in 12 men and 1 in 200 women around the world. It’s an incurable, inherited condition that makes it difficult to distinguish between certain colors. Fortunately, researchers from the U.K.’s University of Birmingham have come up with a way to help. They’ve developed contact lenses that could be used to correct color-blindness the way that regular contact lenses can improve the vision of individuals who are nearsighted or farsighted.
The lenses contain a special dye that is able block certain wavelengths of light. This solves one of the causes of color-blindness, a genetic deficiency in the cluster of cells in the eye (called “optical cones”) that allow us to perceive light. Each cone picks up a different wavelength of light. Combining multiple cones allows us to see the full spectrum of colors. When the cones are working correctly, that is.
The dye used by the University of Birmingham researchers blocks the band of light between the red and green wavelengths, which is perceived by two sets of corresponding cones at the same time. Removing this band makes it easier for people to differentiate between red and green — the most common form of color-blindness.
“We found dyes which are non-toxic and biocompatible, so won’t cause any harm to living cells in the eye,” Dr. Haider Butt, lead researcher from the University of Birmingham’s Department of Mechanical Engineering and the Institute of Healthcare Technologies, told Digital Trends. Butt pointed out that the lenses can even improve the vision of people who don’t have color-blindness, since they increase the contrast between colors.
This project isn’t the first to explore this technique. The company EnChroma already produces sunglasses that function in the same way, although as of yet, no one produces contact lenses that perform this task. “I think a lot of it will come down to personal choice on the part of the patient,” Butt continued, describing the difference between glasses and contacts. “Contact lenses have less of a footprint than glasses. Some patients also don’t want to advertise their disability, which makes contact lenses a good solution because it’s less apparent to others. Contact lenses can additionally be a lot cheaper than glasses.”
Looking forward, Butt said he doesn’t want to commercialize the technology, but rather to “open source” it so that people can potentially create the dyes in the privacy of their own home. This would allow patients to experiment with different concentrations to find a personalized, optimal solution, while keeping the cost down.
A paper describing the project was recently published in the journal Advanced Healthcare Materials.