Do Color Blind Glasses Work?
Sometimes, for some people, with some colors. Here's how they actually work and what to realistically expect, without the marketing.
The idea: a notch filter
Most "color blind glasses" use a notch filter, a lens that blocks a narrow band of wavelengths in the region where the red and green cone responses overlap the most. In common red-green deficiency, the red and green cones are shifted so their signals overlap too much, which is what reduces the contrast between those colors. By cutting the overlapping band, the filter can make the remaining red and green signals more distinct.
Who they tend to help, and who they don't
- May help: people with anomalous trichromacy (mild-to-moderate red-green deficiency), whose cones are shifted but still present. Some report that reds and greens look more vivid and separable.
- Little effect: people with dichromacy (a cone type effectively missing), there's no overlapping signal to recover, and typically no benefit for blue-yellow (tritan) deficiency.
- Varies a lot: the effect differs between individuals and between bright daylight and indoor lighting.
What they can't do
They don't cure color blindness or restore normal color vision; they can't add cone function that isn't there. They shift and enhance contrast; they don't let you "pass" a clinical test or reveal colors your eyes physically can't distinguish. Reviews and studies show real but modest and inconsistent benefits, which is why it's worth trying before buying if you can, and being skeptical of dramatic before/after claims.
This page is general information, not medical or purchasing advice. An optometrist can assess your specific type and whether a filter is likely to help you.
Frequently asked
Do color blind glasses actually work?
For some people with mild-to-moderate red-green deficiency, notch-filter glasses can make certain colors look more distinct and vivid. They don't work for everyone, they don't cure color blindness, and they do little for the strong (dichromat) forms. Results vary a lot between individuals.
How do color blind glasses work?
They use a filter that cuts a band of wavelengths where the red and green cone responses overlap. Removing that overlap can increase the contrast between reds and greens for people whose cones are shifted but still present.
Can color blind glasses give me normal color vision?
No. They can enhance contrast between some colors for some people, but they don't add missing cone function or make your color vision normal, and the effect can differ indoors versus in daylight.