New Look for the Colorblind
New Look for the Colorblind
While a new type of eyeglass lens won't bring a full rainbow of hues to the eyes of the colorblind, it may help some enjoy a more colorful life.
The ColorMax lenses work by shifting the wavelengths of the light entering the eye towards the longer end of the visible spectrum, Bailey says, making it easier for the eye to distinguish between the "warm" colors -- reds, yellows, and oranges. However, the wavelengths of colors at the shorter end of the spectrum -- blues and purples -- are also shifted. These may actually become slightly harder to distinguish. Greens fall in the middle and are less noticeably affected. The result is not "normal" vision, but an enhanced contrast between colors.
When Siciliano first tried the lenses, he could instantly see many more variations in shades of color. "You have to relearn all of the colors with the glasses on," he says. "Someone has to tell you, 'that is red.' You say, 'OK, that's red,' and work from there."
Even the U.S. Food and Drug Administration was careful to point out limitations of the ColorMax lens coating technique when the agency approved it in November 1999. "The lenses do not help wearers perceive or appreciate colors as people with normal color vision do, but merely add brightness/darkness differences to colors that are otherwise difficult or impossible to distinguish," says an FDA "Talk Paper." The FDA says that any promotion of the lenses as "a way to correct colorblindness" may be "misleading."
Many eye experts are similarly cautious. "The problem is that there is not a lot of information available to judge them," says Jeffrey Weaver, OD, the director of the clinical care group of the American Optometric Association. "I don't have the clinical trial information, although I've asked for it. I'm not going to be convinced of anything until the ColorMax researchers publish a paper on it."
Ophthalmologist Joel Pokorny, PhD, of the University of Chicago's visual sciences department, says he is "open" to the idea of the lenses, "but I don't think you're going to gain much. There is a theoretical possibility that they could improve some discrimination of color in the real world, but it's a trade off. You will lose some discrimination as well. But overall, they could help a little bit."
New Look for the Colorblind
While a new type of eyeglass lens won't bring a full rainbow of hues to the eyes of the colorblind, it may help some enjoy a more colorful life.
The ColorMax lenses work by shifting the wavelengths of the light entering the eye towards the longer end of the visible spectrum, Bailey says, making it easier for the eye to distinguish between the "warm" colors -- reds, yellows, and oranges. However, the wavelengths of colors at the shorter end of the spectrum -- blues and purples -- are also shifted. These may actually become slightly harder to distinguish. Greens fall in the middle and are less noticeably affected. The result is not "normal" vision, but an enhanced contrast between colors.
When Siciliano first tried the lenses, he could instantly see many more variations in shades of color. "You have to relearn all of the colors with the glasses on," he says. "Someone has to tell you, 'that is red.' You say, 'OK, that's red,' and work from there."
Even the U.S. Food and Drug Administration was careful to point out limitations of the ColorMax lens coating technique when the agency approved it in November 1999. "The lenses do not help wearers perceive or appreciate colors as people with normal color vision do, but merely add brightness/darkness differences to colors that are otherwise difficult or impossible to distinguish," says an FDA "Talk Paper." The FDA says that any promotion of the lenses as "a way to correct colorblindness" may be "misleading."
Many eye experts are similarly cautious. "The problem is that there is not a lot of information available to judge them," says Jeffrey Weaver, OD, the director of the clinical care group of the American Optometric Association. "I don't have the clinical trial information, although I've asked for it. I'm not going to be convinced of anything until the ColorMax researchers publish a paper on it."
Ophthalmologist Joel Pokorny, PhD, of the University of Chicago's visual sciences department, says he is "open" to the idea of the lenses, "but I don't think you're going to gain much. There is a theoretical possibility that they could improve some discrimination of color in the real world, but it's a trade off. You will lose some discrimination as well. But overall, they could help a little bit."
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