Most people see colours similarly, meaning we all see colours like red and blue in almost the same way. However, some people have colour blindness, also called colour vision deficiency, which means they see colours differently than most people. There are different types of colour blindness, and they can cause significant challenges in distinguishing colours.

The red-green colourblindness is the most common type of inherited colour vision problem, usually caused by a defect in either the red or green cone cells in the eye. Red cones are called L-cones, green cones are called M-cones. Defects in these cones lead to four different types of colour blindness.

Protanomaly

Protanomaly is caused by abnormal red cone cells. People with this condition see red, orange, and yellow as greener and less bright than usual. It is a mild condition and does not significantly affect daily life.

Protanopia

Protanopia is more severe, which means there are no functioning red cone cells. Red appears as black, and shades of green, orange, and yellow all look like yellow. Both protanopia and protanomaly affect about 1% of males.

Deuteranomaly

Deuteranomaly is due to abnormal green cone cells. Greens and yellows appear redder, making it difficult to tell them apart. This mild condition affects over 6% of males and does not interfere significantly with daily activities.

Deuteranopia

Deuteranopia means there are no working green cone cells. Reds look light brown or dark yellow, and greens appear beige. It is less common, affecting less than 1% of males.

Ishihara Test: The Gold Standard

Eye care providers often use the Ishihara test, the gold standard for detecting red-green colour blindness in adults. During the test, the provider shows you a set of 8 to 38 plates, each containing a number or symbol made up of coloured dots. You then tell the provider what you see. The results indicate if you have a type of red-green colour blindness. However, this test does not detect blue-yellow colour blindness.

Anomaloscope: The Most Accurate Test

The first anomaloscope was developed in the 20th century and has since become the most accurate instrument for testing colour blindness, used by eye specialists worldwide.

An anomaloscope tests colour vision based on colour matching. It uses two different light sources that need to be matched to the same colour. On one side, there is a yellow light that can be adjusted in brightness. On the other side, there are red and green lights whose proportions can vary.

This device evaluates an individual's Rayleigh matches, determining the proportions of red and green light needed to match a yellow light. Modern anomaloscopes like the Neitz OT and Oculus Heidelberg work similarly to the original Nagel anomaloscope, which is no longer available.

During the red-green colourblindness test, the patient sees a bi-field: one half is a mix of red and green lights, and the other half is a yellow light. The red/green mixture and the yellow light's intensity can be adjusted. Usually, the practitioner sets the red/green mixture, and the patient adjusts the yellow light's brightness to achieve a match. Alternatively, the patient might control both fields to find a match.

Paediatric Colour Vision Testing: Early Detection in Children

Children often don't realise when their vision isn't normal and may not be able to communicate any issues they're experiencing. This makes it challenging for parents to detect vision problems. That's why regular eye examinations are crucial.

Eye examinations at COLORON

At COLORON, we perform a thorough red-green colour blindness test to assess various aspects of eye health. We check for difficulties in colour vision that help us identify any vision problems you or your child might have. Detecting issues early allows us to address them promptly.

Conclusion: Finding the Best Test for You

By filtering out wavelengths with the most overlap, the COLORON Experience and Strong lenses enhance colour distinction. This expands the range of colours and shades, helping individuals with protan (red) and deutan (green) colour vision deficiencies to see colours more accurately.

Colour vision-enhancing clips are not a cure but a flexible tool that can be used as needed to improve colour vision or red-green colour blindness.

Our blue light-filtering optics, included in the base frame, do more than hold your prescription lenses. They protect your retinas from harmful light waves, which is essential for preserving healthy colour vision over time.

Our colour vision research spans over 20 years, and we take pride in our scientific and fact-based approach. We have conducted hundreds of examinations to inform our development of solutions, including a red-green colour blindness test designed to assist the majority of people with red-green colour deficiencies worldwide.

Take your free colour blindness test online at COLORON and start looking through a lens of colour at your surroundings.