E-mail Support: info@enchroma.com
Customer Service: +1 (510) 497-0048
Business Hours: 7AM-5PM PST

Frequently Asked Questions

EnChroma is aware that some people with color blindness have a strong desire to pass screening tests in order to gain access to occupations where good color vision is required. We are also aware of the existence of certain devices on the market that claim to help people overcome these tests, however there is no evidence that these products are safe to use in color-critical occupations and they are not accepted by any regulatory authorities.

EnChroma’s mission is to make make lens products that help people see color better that are also accepted by the vision science community as being scientifically valid, effective, and safe for use in a broad range of situations.

We believe that our lenses can help on certain types of tests which are used in occupational screening.  The details of which tests and under which conditions success can be expected is a subject currently being studied. EnChroma is currently engaged in collaborations with medical and scientific professionals to establish these results and to establish accepted protocols for administration of color vision tests with our assistive lenses.

These studies are a necessary step in order for our products to gain acceptance by regulatory authorities to permit their use in restricted occupations. However, since these studies are still in progress, we cannot at this time recommend the use of our products with color vision tests, nor for use in occupations where there are specific requirements on color vision acuity, such as emergency first responders, marine, pilot and public transport operations.

If you are a professional involved in administration of color blindness tests and are interested in conducting trials with the EnChroma lens, please contact us by email at research@enchroma.com.

To stay up to date with news from EnChroma and product developments, please subscribe to our email newsletter at enchroma.com/subscribe.

An order that is “processing” means that we have not yet packaged the requested item.

Due to some growing pains and sudden changes in order volume, we occasionally run out of stock in certain items. We receive new glasses from our manufacturing facility on a regular basis, but sometimes an order may be stuck in “processing” for a few days until the item is packaged and ready to go. We do our best to contact all customers who may be experiencing an unexpected delay in order completion.

If your order is for prescription glasses, it will take extra time to complete. It takes 7 business days to make a pair of single-vision lenses and 9 business days for progressive lenses.

Once we have received your complete prescription information the customer service department should confirm that the Rx job is in the system and will be completed soon.

If you have any questions about the estimated delivery date for a particular item, or special needs regarding its delivery schedule, please contact our customer support team by e-mail at crm@enchroma.com.

When your order is placed on EnChroma.com our credit card processor places a temporary hold on the funds in your account. This will reduce the available credit on your account, however we technically don’t have the money yet. When your item is actually shipped from our warehouse we will “capture” the funds. The initial “authorize & hold” event and the “capture” event may both appear on your statement, but they are both actually part of the same transaction.

For security reasons our computer systems do not actually save your credit card information. Its not possible for us to actually charge your card more than once.

Clip-ons are a great way to add the EnChroma Cx functionality on top of a standard prescription eyeglass.

This is not available from us yet but we are currently working on finding a suitable method for filling this need.

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All EnChroma lenses come with a premium anti-reflection coating, plus hydrophobic and oleophobic coating.

We do not use a particular name-branded coating process. However, we do employ rigorous testing and quality control in our manufacturing: our AR+hydro coatings have been subjected to environmental and durability testing and found to be on par with premium name-brand coatings.


  • Anti-reflection coating: This is a multi-layer interference coating that improves clarity of the lens and reduces reflections and “ghost images” on the lens.
  • Hydrophobic coating: This is an ultra thin single layer coating that repels water. It gives the lens a slick, slippery feeling which does not allow water to stick to the surface. The hydrophobic coating also makes it much easier to clean the lens
  • Oleophobic coating: An additional, ultra-thin single layer coating that repels oil: especially, the oils from your fingers or skin. This coating also improves the ease of cleaning the lens.

We believe this will eventually be possible, but there is no concrete timeline as to when it could be available.

Incorporating the EnChroma technology into a contact lens will require rigorous testing to prove that the resulting product is 100% bio-compatible.

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The EnChroma Cx is not polarized. We expect it will someday be possible to make our lens including a polarizer but there is no estimate yes as to when that will be available.

To get informed about new product developments please subscribe to our newsletter.

Reducing the overall light level makes color vision tests more difficult. The EnChroma sunglass lens is generally considered too dark for use with a computer display, so one should not necessarily see an improvement in test score with the eyewear. When used outside in bright daylight, the reduced brightness does not have this potentially negative impact on color perception.

We are currently working toward development of lenses that will be effective in a broader range of conditions including on computers, but there is no concrete timeline for when that will be ready. Subscribe to our newsletter to get informed about new product developments when they are announced.

Tritan-type color vision deficiencies (tritanomaly and tritanopia) are not as common as the red-green type of deficiencies (deutan and protan). Sometimes tritan CVD can be congenital but is more frequently something that develops later in life due to early formation of cataracts or glaucoma, or simply the natural aging of the efficiency of the eye. However, the EnChroma color blindness test when self-administered is not a reliable medical diagnosis. Please contact an eye care professional for more information.

The EnChroma lens actually enhances all primary color simultaneously including red, green and blue: not just red and greens. In principle it should help for tritan cases (blue-yellow CVD) in addition to deutan and protans (both red-green CVD).

We have done some testing with tritan-type deficiencies with positive results, but we don’t have enough data yet to make a firm prediction for your case.

The approximately 20% of cases who are not helped by EnChroma are usually those with very strong deficiency (called dichromats)–if you are a mild to moderate case of any type then it will probably be effective.

EnChroma glasses are functionally sunglasses and work best under outdoor daylight. The darkening effect is a necessary part of how the filtering removes light from the spectrum to enhance color perception. As such they are obviously not usable in all situations as a “full-time use” lens.

We recommend that you wear the EnChroma glasses whenever you go outside. 1) this ensures that the lens is functioning with proper lighting, 2) the diversity of colors in the natural world is rich and will engage your visual cortex functions for color perception, and 3) doctors recommend wearing sunglasses as often as possible to protect the eyes from damaging UV radiation.  EnChroma glasses are qualified as sunglasses and are 100% UV-blocking.

Many customers have reported a “persistence effect” such that they feel their overall color perception is improved after wearing the EnChroma glasses for a long period of time (several months).  They start to notice colors “unaided” that they would not have noticed otherwise. We have not yet done a long-term study of color acuity to quantify this claim, however we believe this effect may be caused by neural plasticity (learning) in the visual cortex.

EnChroma products ship from the USA to countries around the world. UPS Worldwide services takes about 1 week to reach most locations. However please note that additional duty and taxes may be imposed when the product is imported to your country.

The following are estimated import duty rates plus local sales tax for sunglasses:

Canada: 5% (+10% GST)
Brazil: 60% (+40% ICMS)
Australia: 5% (+10% GST) (0% if total purchase less than AUS $1000)
China: 12% (+17% VAT)
Russia: 5% (+ 12% VAT) (0% if total imports less than $1000.00 per month)
France: 2.9% (+ 7% VAT)
Japan: 5.3% (+ 5% Consumption Tax)
United Arab Emirates: 5%
India: 10%

EnChroma does not guarantee that the estimated duty rates given above are accurate. A local sales tax (GST, VAT, Consumption tax, etc) may be imposed in addition to the import duty given above. EnChroma is not responsible for any additional fees or taxes imposed during importation of the product. If you do not pay these fees at time of importation it will be abandoned and destroyed by the customs office. In this event we will not be able to provide a refund of the product. Please do not refuse international shipments!

If you would like to get an estimate of the total landed cost of a product to your location, please contact customer service and include your destination shipping address.

Due to U.S. export laws, EnChroma may not ship to Iran, Cuba or any other country prohibited by U.S. law. EnChroma is not able to refund duty or taxes imposed during importation–please contact your local customs office prior to returning any item to us from outside the USA.

With the EnChroma lens, colors appear brighter and more saturated. People report that their color discrimination is faster and more accurate, they are able to see more vibrant colors. They are more likely to notice objects that are differentiated against a background based on color (such as a flower against background of leaves), whereas without the lens those objects would have been overlooked.

In our user trials, people with color blindness also noticed that the EnChroma lens helped them to differentiate textures within a single shade of color—for example the pattern of different shades of green on a leaf, or in a complex textures such as a hillside covered in trees may appear to be “less noisy”.

Based on our product effectiveness studies, we have found that EnChroma glasses are effective for about 80% of cases of color blindness.  The results vary depending on the type and extent of color vision deficiency. You can get an estimate of your type by taking our online test at EnChroma.com/test.

The EnChroma Cx lens causes a very powerful “super-color enhancement” effect. The same “boost” that it gives to the vision of a person with color blindness can be appreciated with normal color vision as well. In addition, the lens also has a neutral color balance, which means that your sense of color accuracy is not compromised or disturbed.

We have received testimonials from some customers who have normal color vision that the glasses have beneficial effects on their mood, such as from seasonal affective disorder. While this is an interesting potential application, this particular use case has not been studied in detail yet and we do not have any official claims that can be made regarding this use.

The EnChroma Team all wears the Cx Sunglasses, even though most of us are not color deficient–and we love wearing them!

EnChroma is currently available in some locations, however the number of locations is still very limited. Most of our customers choose to buy the product online from our website–if it does not help your color vision the glasses can be returned within 30 days.

To check for a location near you please consult our retailer list: EnChroma Retailers.

All EnChroma products are satisfaction guaranteed for 30 days from the date of order fulfillment. You can return or exchange the product at your option. If you want to exchange for a frame of higher value we will need to charge you for the difference.

If you have any questions about ordering please do not hesitate to contact us.

To initiate a return please contact our customer service department by email at crm@enchroma.com.

Please note that you will be responsible for the cost of shipping when sending products back to us. For orders outside the USA please note that EnChroma is not responsible for any imposed duty or taxes imposed by your local government. To obtain refunds for those fees consult your local customs office.

The EnChroma Cx lens was invented under NEI-sponsored research conducted by Dr. Don McPherson. NEI is the National Eye Institute, a division of the NIH. This research, carried out under an SBIR (Small Business Innovation Research) grant in three phases, included clinical trials of early stage prototypes at UC Davis Eye Center and at the UC Berkeley School of Optometry.

The findings of the study are that scores on the Farnsworth D15 test can be improved for some individuals, provided that 1) the light source is an accurate simulation of natural daylight and 2) the type and severity of the color vision deficiency are within the range that responds well to correction. In addition, subjective testimony was collected in the study which demonstrated clear benefit of the eyewear to color deficient individuals in real-world situations.

We have also examined the efficacy of the eyewear on color blindness screening tests such as the Ishihara plate test. Results here are mixed: these tests are “pass-fail” screening tests and are designed to be extremely difficult to catch even the most mild cases. A person with strong color vision deficiency may enjoy a boost to their color perception while wearing EnChroma, yet still show evidence of mild deficiency under testing–therefore they will still fail. Our position is that improvement to color vision cannot be measured meaningfully with a screening test. Furthermore, such tests are used in occupations where public safety is a concern (e.g. public transport operators), and therefore should not be circumvented. EnChroma glasses should be used to for improvement of quality of life and color vision generally, and not for the purpose of bypassing an occupational restriction.

In our experience with in-house product testing and our customer base, we have observed that results with EnChroma vary depending on the type and severity of color vision deficiency.  Certain cases of very strong color blindness are, unfortunately, simply too strong to help. These cases, called dichromats, make up about 20% of the population of people with color vision deficiencies.

To get an estimate of how well EnChroma glasses will help you, use our online color blindness test to estimate the type and severity of your deficiency. Visit EnChroma.com/test to get started.

Since the first scientific recognition of color blindness in the 1790s, numerous inventions and therapies have been attempted to correct for color blindness. The first glasses for assistance with color blindness date to the 1850s and were created by James Maxwell. These glasses featured a lens having an arrangement of three differently tinted segments arranged vertically: red on the top, clear in the middle and green across the bottom. One could presumably determine the color of an object by comparing the relative brightness of its appearance in each section of the lens. Essentially it could be called a “color vision trifocal” design.

Around the time of World War II (1940s) the public awareness of color blindness increased greatly as people wanted to volunteer to fly in the air force. Flying a plane (especially at night) requires good color vision, squashing the dreams of many eager young men. Consequently, the market was flooded with “cures” for color blindness offered by unscrupulous proprietors with the promise of passing a color blindness test. These ranged from benign frauds to outright dangerous procedures such as a doctor who would actually inject snake venom into the eye. Please note that color blindness cannot be cured, and that occupational testing is required for reasons of public safety (e.g. public transport operators) and should not be circumvented.

Since the 1970s a variety of lens products have been marketed which take the form of tinted lenses applied monocularly or binocularly with different tints in each eye. The tints are usually a strong red, purple or pink color.  Often the tint is put into a contact lenses, making the solution relatively discrete. While such devices can in theory provide additional spectral information, it is understood according to vision science that these devices work on the principle of binocularly rivalry (disruption of depth perception) and do not fundamentally improve color vision. Due to the low risk and possible benefit to some individuals, the FDA has permitted such devices to be sold provided that they are clearly labeled that 1) they are not a cure for color blindness and 2) have minimal therapeutic effectiveness.

EnChroma is based on a unique approach to color blindness correction: restoration of the spectral separation between cones using a narrow-band notch filter. The effect works for people with forms of anomalous trichromacy, which are the majority of cases (about 80%). The notch filter, when designed correctly, can be provided without inducing a color tint to the lens–it appears to look like an ordinary sunglass lens. Unlike conventional color-tinted lenses which distort colors–emphasizing one color at the expense of others, EnChroma lenses amplify the perception of all three primary colors simultaneously (red, green and blue). The result is a “boost” to the chromatic saturation (purity or vividness) of colors.

Technical details aside, we welcome you to examine our testimonial evidence from happy customers and consider making the investment yourself. If for any reason you are unsatisfied with the purchase, EnChroma products can be returned and refunded at any time within the 30-day trial period.

The names you see in our product catalog, “Apollo”, “Explorer”, etc, refer to the frame style. All frames we sell come with the same lens for color blindness correction, which is called the “Cx“.

Frame styles can be broadly classified according to their intended use:

You can also get the EnChroma lens fitted in a third-party frame of your choice.

Yes. The EnChroma Cx lens is fully compliant with limits on minimum brightness and chromaticity coordinates of traffic signals as defined by American National Standard ANSI Z80.3-2010. They perform well and as a non-polarized lens allow you to better see oil and other slippery surfaces on the road.

According to the European Union CE standard EN 1836:2005+A1:2007, the lens may be considered “not suitable for driving and road use”. We believe the CE fails to anticipate the technological capabilities of the EnChroma lens with the method used to quantify lens performance with respect to traffic signals.

Please use common sense judgement to ensure that the lens does not cause your color perception to be altered in such a way that it would be difficult to interpret traffic lights and signs.

Please contact us by email at info@enchroma.com. The EnChroma lens can be dispensed and prescribed according to standard procedures in the eyecare industry.

EnChroma glasses are intended for outdoor use in natural daylight. They are not intended for use with computers, TVs or other display devices. Generally the lens would be considered too dark for using a computer.

However, some customers have reported using the lenses for activities such as watching TV. Results vary depending on the type of display being viewed.

You will need a medical professional to certify that “the expenses are a direct result of a medical condition,” and that the expense is to alleviate that condition. A form for documenting that is provided here: https://www.fsafeds.com/forms/MedicalNecessity.pdf.

Many EnChroma customers have successfully claimed coverage under the U.S. FFSA guidelines. However, please note that EnChroma does not guarantee validity of such claims.

Yes. Children are usually diagnosed with color vision deficiency when they enter grade school. In most school systems color vision screening is mandatory because it has significant effects on classroom learning.

EnChroma Cx glasses are available in a variety of pediatric styles. Check the recommended age-range for the frame prior to purchasing.

EnChroma Cx glasses in pediatric frames are fitted with polycarbonate lenses. Polycarbonate is the #1 doctor-recommended lens material for children due to its super-tough impact resistance.

Red-green color blindness is caused when the spectral response of the M-cones and L-cones are shifted so they are more overlapping than normal. The greater the amount of overlap, the more severe the color vision deficiency will be, and the harder it is to provide a corrective aid that is effective.

About 20% of cases of color blindness can be classified as types of dichromacy.  Dichromats are defined as individuals having a total (100%) overlap of M-cone and L-cone sensitivity. EnChroma works by creating a “spectral notch” that restores separation between the cones. However, if the cones are 100% overlapping then it is impossible for such a notch to have any effect. In essence, this case is simply too strong to correct. Types of dichromacy include protanopia, deuteranopia and tritanopia.

However, we have also found in product testing that some people nominally considered “dichromats” may actually be forms of strong anomalous trichromacy, meaning that the overlap is less than 100%. These people have very strong color vision deficiency, but are still able to get some help from the EnChroma lens. Typically a person with a very strong color vision deficiency will mainly see improvement in the color appearance of traffic signals but may not be able to get the “super color vision” experience in the natural world that is reported by persons with less severe impairment.

EnChroma’s online color blindness test can be used to estimate the type and extent of your color vision deficiency. On completion it will advise you of the probability that EnChroma lenses can help you. If the product does not help it can be returned within the 30 day trial period.

There are many different providers of vision insurance, and their coverage & plans vary. Some insurance plans provide a general benefit that can be applied to any prescription sunglass lens. If so this benefit may be applicable to the EnChroma Cx lens which is also a type of sunglass lens intended for outdoor use.

Please contact your insurance provider to find out if EnChroma lenses are covered.

Yes. If you normally wear glasses for correction of your distance vision, then you will want to get the EnChroma lens made with your prescription.

EnChroma glasses are intended for outdoor use which generally means they are not used for near-vision correction. So, if you only wear prescription glasses for correction of near-vision (e.g. reading, office work, etc), then you may not need to order the prescription lenses with EnChroma.

Prescription types:
Our glasses can be made with single vision prescriptions as well as bifocal and progressive corrections. You can order a frame with your prescription via our website, or via an authorized eyecare professional that carries EnChroma.

Normal Prescription range*:
Single Vision: SPH -4 to +2 CYL -6 to +6
Progressives: SPH -4 to +2 CYL -4 to +4 ADD +3

EnChroma Cx Prescription lenses are made from polycarbonate.

*Out of range prescriptions may be possible depending details of frame geometry. Please contact us for details.

Note: The EnChroma Cx Non-Prescription and Prescription lenses have the same functionality. You do not need a doctor’s prescription to buy the EnChroma Cx.

You can also get EnChroma with a “fit-over” frame called the Receptor–this can be worn over your regular glasses (see below).