Written By: Reena MukamalReviewed By: Ivan R Schwab MD FACS, Laurie Gray Barber MDJul. 23, 2019
New glasses are advertising an improvement in color vision for people with common forms of red-green color blindness. You may even have seen emotional, viral videos of people trying these glasses on for the first time. But how well do color blindness-correcting glasses really work?
Inherited color blindness — also called color vision deficiency — has no cure today. But for some people with milder forms of red-green colorblindness, specially formulated color-correcting eyeglasses may improve contrast between some colors. The results vary depending on the type and extent of a person’s color vision deficiency.
How Do Colorblindness Glasses Work? Whom Might They Help?
Genetic color blindness is caused by an absence of, or problem in the function of, one or more of the three types of color-sensing cone photoreceptors in the retina. People who have difficulty detecting green light (deuteranomaly) or red light (protanomaly) experience an overlap between some of the light wavelengths that the brain interprets as red or green color.
“Color blindness glasses are made with certain minerals to absorb and filter out some of the wavelengths between green and red that could confuse the brain,” explains Ivan Schwab, MD, professor of ophthalmology at the University of California, Davis.
According to Dr. Schwab, some of the light coming through the glasses is blocked so that the remaining red and green light wavelengths don’t overlap as much. With less color overlap, the brain gets a clearer signal to help distinguish between the problem colors. One of the most popular kinds of these glasses are made by EnChroma.
Color blindness-correcting glasses will not change color perception for people whose deficiency is caused by a complete absence of red or green photoreceptors. And the positive effects of the glasses last only as long as they are being worn. The glasses don’t in any way modify a person’s photoreceptors, optic nerves or visual cortex to fix color blindness.
“Color perception requires a complete set of optimally functioning equipment, and glasses will not replace or repair missing or broken mechanisms,” says Dr. Schwab.
Dr. Schwab explains that the glasses change what the people who wear them see, enhancing the distinction between red and green. But the experience will vary widely among individuals, and color blindness-correcting glasses don’t give people a true equivalent of natural color vision.
What to Consider Before Purchasing Color Blindness Glasses
Because they reduce the amount of light getting to the eye, it might not be a good idea to wear color blindness-correcting glasses at night. Reducing the amount of light getting into the eye might especially be a problem for people who have other eye conditions such as cataracts or macular degeneration. EnChroma, the manufacturer, warns against using the glasses while driving. The company offers an indoor collection that blocks less light, for lower-light conditions.
Cost is also a concern for the average consumer. These glasses may be a luxury item for many individuals, because they can cost several hundred dollars. It’s important for people to have realistic expectations of how much these glasses might or might not help them before they buy. Color blindness-correcting glasses are generally not covered by insurance because color blindness doesn’t affect a person’s health, so treatment isn’t medically necessary.
There are other devices designed to enhance contrast between colors, such as hunting glasses and contrast-increasing filters for photography that may benefit some people. But products other than color blindness-correcting devices like EnChroma glasses weren’t developed specifically to address the experience of people with color blindness.
Dr. Schwab adds, “The [Enchroma] inventors understood visual physiology, color deficiency, and had a thorough understanding of the physics of optics and optical filters. With that combined knowledge they were able to select rare earth minerals that exactly matched the filter restrictions needed to enrich the glasses to address this color deficiency. It’s an elegant meld of curiosity and education to address a problem.”
Source: American Academy of Ophthalmology