The Ishihara test
is commonly used to detect Daltonism
(color blindness of basic colors: red, blue and green).
A distinction is made between:
- protanopes, who do not see red;
- deuteranopes, who do not see green;
- tritanopes, who do not see either blue or yellow.
Tritanopes cannot be identified using a Ishihara test
but instead requires a 100 Hue test, which needs to be carried out by your eye care specialist
Rarer are people with complete color blindness, who only perceive levels of gray. They are said to suffer from achromatopsia.
Place yourself 1m from the screen.
What can you see inside each of these circles?
If you do not manage to read the figures 7, 16, 57 and 42, an eyesight check by an eye care specialist would appear necessary.