These contact lenses can correct color blindness.
Researchers at the University of Birmingham developed a contact lens that uses a special dye to help people with red-green color vision deficiency (CVD), which is the most common form of color blindness.
Our eyes see colors thanks to clusters of cones that perceive blue, green, and red wavelengths. When certain cones are missing, our brain receives the wrong information about colors. But the dyed lenses block the color band that lies between red and green wavelengths this means that red and green cones don’t have to sense colors simultaneously, and the eye has an easier time perceiving red and green. The dye is both non-toxic and inexpensive, compared to similar CVD treatments.
“Contact lenses are of interest for color blindness correction because it is easier to correct the entire field of view,” explained University of Birmingham Lead Researcher Dr. Haider Butt. “The dye processing we carried out does not need a complex preparation, it is not toxic to the human eyes, and our method could be easily used in both glasses and contact lenses at low cost.”
The next step for researchers is to create a lens for purple-blue color blindness and one for both red-green and purple-blue color blindness.