You've probably seen the viral videos: someone puts on a pair of special glasses and is suddenly moved to tears, seeing red roses or a sunset in full colour for the first time. These clips have made color blind glasses one of the most searched-for eyewear products online. But behind the emotional reactions, there's real science — and real limitations — worth understanding before you spend $300 on a pair.
This guide explains how color blind glasses work, what types of color vision deficiency they can (and can't) help, and what you can realistically expect if you try them.
Understanding Color Vision Deficiency
Before talking about the glasses, it helps to understand what color blindness actually is — because it's not what most people think.
Color blindness (more accurately called color vision deficiency, or CVD) rarely means seeing in black and white. In the vast majority of cases, people with CVD see colors — they just can't distinguish between certain ones as clearly as someone with normal color vision can.
How Normal Color Vision Works
Your retina contains three types of cone cells, each sensitive to a different range of wavelengths:
- L-cones (long wavelength) — sensitive to red light
- M-cones (medium wavelength) — sensitive to green light
- S-cones (short wavelength) — sensitive to blue light
Your brain interprets color by comparing the signals from all three cone types. When one type of cone responds slightly differently than normal — or is missing entirely — certain colors become difficult to tell apart.
Types of Color Vision Deficiency
| Type | What's Affected | Prevalence | Severity |
|---|---|---|---|
| Deuteranomaly | M-cones (green) shifted toward red sensitivity | ~5% of males, 0.4% of females | Usually mild to moderate |
| Protanomaly | L-cones (red) shifted toward green sensitivity | ~1.3% of males, 0.02% of females | Mild to moderate |
| Deuteranopia | M-cones completely absent | ~1.2% of males | Severe |
| Protanopia | L-cones completely absent | ~1.0% of males | Severe |
| Tritanomaly/Tritanopia | S-cones (blue) affected or absent | Very rare (~0.01%) | Variable |
| Achromatopsia | All cones absent or non-functional | Extremely rare (~0.003%) | Complete |
The first two types — deuteranomaly and protanomaly — account for about 75% of all color vision deficiency. This is important because these are the types that color blind glasses can actually help with.
Are You Color Blind?
About 1 in 12 men and 1 in 200 women have some form of color vision deficiency. Many people don't realize they have it until they're tested. If you've ever struggled to distinguish red from green traffic lights at a distance, had difficulty with colour-coded charts, or been told you misidentified a colour, it's worth getting tested. A comprehensive eye exam typically includes a basic colour vision screening using Ishihara plates.
How Color Blind Glasses Work
Color blind glasses use a technology called spectral notch filtering. Here's what that means in plain language:
In people with deuteranomaly (the most common type), the green-sensitive M-cones have their peak sensitivity shifted toward the red range. This means the M-cone and L-cone response curves overlap more than they should. The result: reds and greens produce similar signals, making them hard to distinguish.
Color blind glasses contain lens filters that block the specific wavelengths of light where the M-cone and L-cone responses overlap. By removing this "confused" middle zone of light, the glasses increase the contrast between the remaining red and green signals that reach your brain.
The Key Mechanism
- Step 1: The lens identifies the wavelength overlap zone (typically around 540-580nm for red-green CVD)
- Step 2: A multi-layer optical filter blocks light in that specific range
- Step 3: The remaining light that passes through creates a clearer separation between the red and green cone signals
- Step 4: Your brain receives more distinct signals and interprets them as more vivid, separated colours
It's important to understand: the glasses are not adding color information that wasn't there. They're subtracting confusing light so that the colour information your cones can detect becomes more distinct. You're not seeing "new" colours — you're seeing existing colours with better separation.
Who Color Blind Glasses Work For (And Who They Don't)
This is where realistic expectations matter. Color blind glasses are not a universal solution.
Best Candidates
- Mild to moderate deuteranomaly — The most common type, and the one where these glasses show the best results. People with mild deuteranomaly often report the most dramatic improvement.
- Mild to moderate protanomaly — Also responsive, though results may be slightly less dramatic than deuteranomaly because the spectral shift is in the opposite direction.
Limited or No Benefit
- Deuteranopia/Protanopia — When cone cells are completely absent (not just shifted), there's no signal to enhance. Color blind glasses generally have minimal effect for these severe forms.
- Tritanomaly/Tritanopia — Blue-yellow deficiency involves different wavelengths than the glasses are designed to filter. Some newer products claim to address this, but evidence is very limited.
- Achromatopsia — Complete colour blindness involves non-functional cone cells. No external filter can create colour perception where the biological hardware is absent.
What to Realistically Expect
The viral videos show the most dramatic reactions — and those are real, but they represent the best-case outcomes. Here's a more balanced picture of what most users experience:
- Outdoor performance is better than indoor. Color blind glasses work best in bright, natural light. Indoor results under artificial lighting are typically less impressive.
- The effect builds over time. Many manufacturers recommend wearing the glasses for 15-30 minutes before judging the effect. Your brain needs time to adapt to the altered colour signals.
- Not everyone notices a difference. Approximately 20-30% of users report little to no perceptible improvement, depending on the severity and type of their deficiency.
- Colours may shift, not "appear." Rather than suddenly seeing red for the first time, many users describe existing colours becoming more vivid and distinct from one another.
- The glasses don't work in the dark. Since the mechanism depends on filtering ambient light, they require adequate lighting to function.
The Science: What Studies Show
Research on color blind glasses is still relatively young, but several peer-reviewed studies provide insight:
A 2020 study published in Optics Express by researchers at UC Davis tested EnChroma lenses on 48 subjects with red-green CVD. They found that the glasses improved colour discrimination on the Farnsworth D-15 test for mild to moderate deficiencies but showed no significant improvement for severe deuteranopia or protanopia.
A 2022 study in Clinical and Experimental Optometry tested 34 participants and found that while the glasses improved subjective colour experience, they did not restore normal colour vision on standardized clinical tests. The improvement was real but partial.
The consensus: color blind glasses provide a meaningful enhancement for many people with mild to moderate red-green CVD, but they are not a cure and do not replicate normal colour vision.
Color Blind Glasses: Cost and Insurance
Color blind glasses are a significant investment:
| Product Type | Approximate Cost (CAD) | Notes |
|---|---|---|
| Non-prescription (outdoor) | $250 — $400 | Sunglass-style tinted lenses, best results |
| Non-prescription (indoor) | $300 — $450 | Lighter tint for indoor use, subtler effect |
| Prescription (single vision) | $400 — $700+ | Custom Rx combined with colour filtering |
| Prescription (progressive) | $500 — $800+ | Progressive + colour filtering |
Most Canadian health insurance plans do not cover color blind glasses because they're classified as an elective rather than medically necessary device. However, your standard optical benefit from plans like Alberta Blue Cross, Canada Life, or Desjardins can still be used toward your regular prescription eyeglasses — so you might use insurance for everyday glasses and pay out-of-pocket for color blind glasses as a secondary pair.
Check your insurance provider's coverage details for specifics on what qualifies under your optical benefit.
Getting Tested and Finding Options
If you're considering color blind glasses, the process should start with a proper assessment:
- Get a comprehensive eye exam. A full eye exam will check your overall eye health and identify the specific type and severity of your colour vision deficiency. This information is essential for selecting the right lens type.
- Identify your CVD type. Ask your optometrist to perform a detailed colour vision assessment (beyond the basic Ishihara screening). This might include an anomaloscope test or the Farnsworth-Munsell 100 Hue test, which classify your deficiency more precisely.
- Research product options. EnChroma is the most well-known brand, but Pilestone, VINO, and ColourMax also produce colour-enhancing lenses. Most offer online colour vision tests to estimate whether their product will work for your specific type.
- Try before you buy if possible. Some optical retailers stock demonstration pairs. Since the effect varies dramatically by individual, trying the glasses in person is the best way to know if they'll work for you.
Important Note on Children
Color vision deficiency is typically inherited and present from birth, but most children aren't diagnosed until school age (when they struggle with colour-coded activities). If your child is having difficulty with colours, an eye exam with colour vision testing can provide answers. Early identification helps with school accommodations, even if color blind glasses aren't immediately pursued. Children's vision care is a critical part of their development and learning.
Living with Color Vision Deficiency
Whether or not you pursue color blind glasses, there are practical strategies that help with daily life:
- Label items by name, not colour — Mark clothing, paint cans, and office supplies with text labels
- Use colour identifier apps — Smartphone apps like Color Blind Pal and Colour ID can identify colours in real time using your camera
- Request accessible design — Many digital tools now offer colour-blind-friendly modes. Don't hesitate to ask workplaces and schools for accessible materials
- Know your traffic lights by position — Top is red, bottom is green. In Canada, many newer signals also include shape indicators
- Get regular eye exams — While CVD itself doesn't change over time, acquired colour vision changes in adulthood can signal other conditions like cataracts, glaucoma, or diabetic eye disease. Annual exams help catch these early.
The Bottom Line
Color blind glasses are a genuinely innovative technology that can make a meaningful difference for many people with mild to moderate red-green colour vision deficiency. But they're not magic, and they don't work for everyone. Set your expectations realistically: if you have mild deuteranomaly, there's a good chance you'll notice an improvement in colour distinction. If you have severe or complete colour blindness, these glasses likely won't provide much benefit.
Start with a proper diagnosis from a qualified eye care professional, understand your specific type and severity of CVD, and then make an informed decision about whether color blind glasses are worth the investment for your situation.
Frequently Asked Questions
Color blind glasses can enhance colour distinction for people with mild to moderate red-green colour vision deficiency. They work by filtering specific wavelengths to increase contrast between confused colours. However, they don't cure colour blindness or create normal colour vision — they enhance the separation between red and green signals that your existing cones can detect.
Non-prescription color blind glasses typically cost $250-$450 CAD. Prescription versions range from $400-$800+. They are generally not covered by insurance, but your regular optical benefit from insurance providers can be used toward everyday prescription glasses, allowing you to budget separately for color blind glasses.
No. They are most effective for red-green deficiency (deuteranomaly and protanomaly), which accounts for about 99% of cases. They have limited effect on blue-yellow deficiency and do not work for complete colour blindness (achromatopsia). A comprehensive eye exam can determine your specific type and whether these glasses might help you.
Most users describe colours as more vivid and distinct — reds appear redder, greens appear greener, and colours that previously looked similar become distinguishable. The effect is strongest outdoors in bright light. Some people experience a dramatic reaction, while others notice a more subtle improvement. Results vary based on the type and severity of your deficiency.
The most reliable test is the Ishihara plate test, usually included in comprehensive eye exams. Signs you might have colour vision deficiency include confusing reds with greens, difficulty with colour-coded information, or being told by others that you misidentify colours. About 1 in 12 men and 1 in 200 women have some form of CVD.
Sources & Further Reading
- National Eye Institute — Eye Conditions — Comprehensive eye disease database
- Mayo Clinic — Eye Diseases — Medical guidance on eye conditions
- American Academy of Ophthalmology — Eye Health A-Z — Peer-reviewed disease information
- Canadian Ophthalmological Society — Canadian eye disease prevention resources
- National Eye Institute — Color Blindness — Types, causes, and testing for color vision deficiency