Colour Blind Test - Online Self Test
You may have heard of colour blindness but not really know exactly what it means. Find out everything you need to know about the causes, symptoms, tests and treatment for colour blindness.
What is colour blindness?
Colour blindness is a term for when someone is unable to see colours in a normal way. More accurately, it is a colour deficiency rather than colour blindness. Often, someone may not be able to distinguish between certain colours, most commonly between reds and greens and occasionally blues.
What causes colour blindness?
In the retina of the eye, there are two types of cells, rods and cones, that detect light. Rods detect light and dark whereas cone cells detect colour. Cone cells are concentrated in the central area of the retina in the macula. There are blue, green and red cones and your brain uses input from these cone cells to determine your colour perception.
Colour blindness can occur when there is an abnormality in these colour cone cells. This could either be because there is an absence of cone cells, some of them may not be working correctly or some may detect a different colour than normal.
You usually suffer with colour blindness from birth and generally males are more affected than females. However, you can also acquire it later in life as a result of trauma, diseases including metabolic and vascular diseases, toxic effects from drugs and general aging.
If you experience a significant change in colour perception, you should visit an eye specialist.
Types of colour blindness
Severe colour blindness occurs when all three cone cells are absent, and this is known as achromatopsia. In this case, you will see everything in different shades of gray! Mild colour blindness is when one cone cell does not work properly, and you may see colours normally in good light but struggle in dim light.
Colour blind symptoms
DID YOU KNOW?
Red-green colour blindness is the most common type of colour blindness. As the name suggests,it makes it hard to tell the difference between red and green.
Is there a colour blind test I can take?
You can very easily do a colour blind test online without having to go to an eye specialist. This test, also known as the Ishihara test, is a fast and simple way to determine whether you struggle to perceive colour in a normal way. The test is made of a series of ‘plates’ of coloured dots. In the center, the coloured dots make up a number, and this number is surrounded by coloured dots of a different colour.
Have a go! See the answers at the end of the article.
- Firstly, make sure you have the lights on. If you wear glasses of contact lenses, you can wear them to do the test.
- Look at the patterns made up of multi-coloured dots.
- If you can make out the numbers and shapes among the dots, you do not have a colour deficiency.
- If you struggle to do this, you may have a colour deficiency and it is advised that you visit an eye specialist for a more comprehensive test.
If you are not sure about this test or if you would like more accurate results, visit an eye specialist to take a colour blind test administered by a trained professional using standardized testing materials under proper lighting.
For a colour blind test for kids, it is advised that you book an appointment with an eye specialist.