Colorblind glasses use specially designed light filters to increase the contrast between colors that normally look too similar. They don’t restore normal color vision or “cure” color blindness. Instead, they selectively block narrow bands of light wavelengths where the signals from different color-detecting cells in your eye overlap the most, making it easier for your brain to tell certain colors apart.
The Overlap Problem in Color Blindness
Your retina has three types of cone cells, each tuned to absorb different wavelengths of light: short (blue), medium (green), and long (red). Normal color vision depends on clear differences in how these three cone types respond to any given color. Your brain compares their signals and interprets the result as a specific hue.
In the most common forms of color blindness (red-green deficiency), the medium and long wavelength cones produce pigments whose sensitivity ranges overlap more than usual. People with these conditions still have two sets of long-wavelength cones, one normal and one with a shifted response curve, but because those curves sit so close together, the two cone types send nearly identical signals when they encounter certain colors. The brain can’t extract a meaningful difference, so reds, greens, browns, and oranges blur together.
This is different from complete color blindness, where an entire cone type is missing altogether. Most people diagnosed as “colorblind” actually fall into the overlap category, technically called anomalous trichromacy. They see color, just with less distinction between certain hues.
How the Filters Separate Colors
Colorblind glasses contain what optical engineers call notch filters. Rather than tinting all light evenly like ordinary sunglasses, notch filters cut out very specific, narrow slices of the visible light spectrum. These slices target the exact wavelengths where the overlapping cone types respond most similarly.
By removing those ambiguous wavelengths, the light that does reach your eye produces more distinct signals in each cone type. The filters are designed to increase the separation between color channels so that colors appear more vibrant, clear, and distinct. Think of it like removing the muddy middle ground between two radio stations that bleed into each other: you don’t get more signal, but you get less interference.
The lenses typically have a reddish or amber tint because they’re filtering out portions of the yellow-green spectrum where red-sensitive and green-sensitive cones overlap the most. This is why the glasses are primarily designed for red-green color deficiency and have little to offer people with blue-yellow deficiency or complete color blindness.
Who Benefits Most (and Who Doesn’t)
The glasses work best for people who still have all three cone types but with abnormal overlap, the anomalous trichromats. If you’re missing an entire cone type (dichromacy), there’s no second signal for the filters to separate, so the glasses have very limited benefit.
Even among anomalous trichromats, results vary. The more overlap between your cone responses, the harder it is for any filter to create enough separation to matter. People with mild to moderate red-green deficiency tend to notice the most dramatic difference, while those with severe forms often report less improvement.
The specific subtype matters too, and the research is mixed on which subtype benefits more. One clinical study using Ishihara plate tests found that error scores significantly improved for people with deutan deficiency (the green-shifted type) but not for protan deficiency (the red-shifted type). However, a separate study using different color discrimination tasks found the opposite: only protan participants showed improvement on certain tests, while deutan participants actually developed more protan-like errors when wearing the glasses. This inconsistency suggests the filters may shift the nature of a color vision deficiency rather than straightforwardly correcting it.
What the Clinical Evidence Shows
The emotional reactions in viral videos are real, but the science behind the glasses is more modest than the marketing implies. In a study published in the journal Optics Letters, researchers found that EnChroma filters shifted the colorimetric coordinates of test figures but did not clearly improve overall color discrimination scores. Their conclusion was direct: the study did not support the efficacy of the filters in correcting color discrimination in colorblind individuals. A separate study from the Association for Research in Vision and Ophthalmology found that anomalous trichromats’ color categories did not differ very much after wearing the glasses for two hours.
That said, one study did find meaningful improvement on the Ishihara plate test, the standard screening tool for color blindness. Participants wearing the glasses had reduced error scores compared to wearing no filter, though the improvement was statistically significant only for the deutan subgroup. So the glasses can help some people identify colors they’d otherwise confuse, even if they don’t fundamentally change the underlying deficit.
The Role of Brain Adaptation
One interesting finding is that the glasses may work better over time. A study published in Current Biology found that people with color deficiencies reported long-term changes in their color perception after wearing the glasses for just a few days. The researchers suggested this happens because the brain learns to interpret the modified color signals in new ways, not because the glasses change anything about the eye itself.
This means the first time you try them on in a store may not represent the full experience. Some manufacturers recommend wearing the glasses for at least 10 to 15 minutes per session, and consistently over several days, before judging the effect. Your visual system needs time to recalibrate to the new input, similar to how your eyes adjust when you first wear prescription lenses.
Practical Limitations
Because the lenses block specific wavelengths, they reduce overall light transmission. Most colorblind glasses work best in bright, natural daylight where there’s plenty of light to spare. Indoor lighting, especially fluorescent or LED sources with uneven spectral output, can reduce their effectiveness. Some brands offer indoor-specific lenses with lighter filtration, but these generally produce a subtler effect.
The glasses also cannot help you pass professional color vision screenings for jobs like airline piloting or electrical work. While some studies show modest improvement on Ishihara tests, the improvement is typically too small and inconsistent to move someone from a “fail” to a “pass” on occupational standards. Most regulatory bodies do not accept test results obtained while wearing color-enhancing lenses.
Prices for colorblind glasses typically range from $100 to over $300 depending on the brand and lens type. Since they are considered optical accessories rather than medical devices, they are not covered by most insurance plans. Given the variability in results, it’s worth checking whether the manufacturer offers a return policy so you can test them with your specific type and severity of color vision deficiency before committing.