What it is
An anomaloscope is an instrument that you look into, usually with one eye at a time. You typically see a small circle divided into two halves. One half shows a single color of light, and the other half shows a mix of two colors that you adjust.
The task is to make the two halves look the same. How a person matches them can give a clinician information about how their color vision works, including whether red-green color vision differences may be present and how pronounced they may be.
An anomaloscope test is one tool among several. It is usually performed by a trained professional, and the results are interpreted by that professional in the context of the full visit. This page is educational only and does not diagnose anything.
How it’s traditionally been approached
Color vision has long been checked with a range of tools. Many people first encounter pictured dot patterns (often called plate tests) or color-arranging tasks, which are commonly used as quick screenings.
The anomaloscope has traditionally been regarded as a more specialized instrument. It is not found in every office, and it generally takes a trained examiner to operate it and explain the results.
Which test is used often depends on the reason for testing, the provider's equipment, and who is being tested. Some settings, such as certain jobs or licensing programs, may name particular tests, and those requirements vary by employer and authority and can change over time.
How the right doctor may help
The right provider may help you understand which color vision tests make sense for your situation. A visit often begins with a conversation about your history, your family history, and why you are seeking testing, followed by one or more color vision tests and a review of what the results may mean.
If an anomaloscope is available, a provider may use it as part of a broader evaluation. It is not always necessary, and your provider decides what is appropriate. Pediatric providers may also adapt their approach for younger children, who can find some tests harder to follow.
Helpful questions to ask include: Which tests do you use, and why? Does your office have an anomaloscope, or can you refer me to one that does? What type and severity of color vision difference do my results suggest? Can you provide a written report if an employer or school asks for one? Color-enhancing filter glasses and contact lenses do not cure color blindness or restore normal color vision, and how well they work varies by a person's specific type (protan, deutan or tritan) and severity, so it is fair to ask a provider whether they are worth discussing for you.
The whole-person view
Seeing is not only about the eyes. The body, mind and stress all affect one another, and learning that you or your child sees color differently can bring up curiosity, relief, frustration or worry. Rest, support and clear information can make the process feel more manageable.
If testing leaves you feeling anxious or overwhelmed, support is available. Somatic Experiences offers body-based support, and Therapists.plus connects people with talk therapy. Neither is a substitute for an eye exam, but some people find extra support helpful as they adjust to new information.
Keep in mind
- This page is educational only and is not medical advice; only a licensed clinician can evaluate your color vision and interpret test results.
- Color-enhancing filter glasses and contact lenses do not cure color blindness or restore normal color vision, and their effect varies by type and severity.
- Career and licensing color vision standards, such as those for aviation, military, law enforcement, commercial driving, electrical trades and maritime work, vary by employer and authority and change over time, so confirm current requirements directly with the employer, licensing body or agency.
- If you have sudden changes in vision or any emergency, call 911; if you are in crisis, call or text 988.
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Frequently asked questions
What is an anomaloscope test?
An anomaloscope test is a color vision exam in which a person looks into an instrument and adjusts a mix of colored lights until it matches a reference color. The way a person makes the match gives a trained professional information about their color vision. It is usually performed by an eye care professional.
What does an anomaloscope test measure?
It is generally used to look at red-green color vision and to help show how pronounced a difference may be. A clinician interprets the results together with other findings from your visit. It is not a stand-alone diagnosis from a web page.
Is the anomaloscope test the same as the dot-pattern color blind test?
No, they are different tests. Dot-pattern (plate) tests are often used as quick screenings, while an anomaloscope is a specialized instrument that may provide more detail. A provider may use one, both, or other tests depending on your situation.
Does an anomaloscope test hurt?
No, the test is generally non-invasive and involves looking into an instrument and making visual matches. It may take some concentration, and your examiner can explain each step. Ask your provider about anything that is unclear or uncomfortable.
Where can I get an anomaloscope test?
Availability varies, and not every eye care office has this instrument. You can ask a provider who offers comprehensive color vision testing whether they have one or can refer you to someone who does. Pediatric color vision testing providers can advise on options for children.
Can color blind glasses fix what an anomaloscope test shows?
No. Color blind glasses, meaning color-enhancing filter glasses, do not cure color blindness or restore normal color vision. Some people find they change how certain colors look, but results vary by the person's specific type (protan, deutan or tritan) and severity. A licensed provider can talk with you about whether they are appropriate.
Educational resource. Colorblind Glasses shares general information and connects people with independent doctors. It is not medical advice, diagnosis or treatment. Talk with a licensed professional about your health.