What is color deficiency?

Colour vision deficiency, commonly referred to as colour blindness, is the reduced ability to see colours compared to a normal person. It is a type of visual disorder that affects a significant number of individuals, with a higher prevalence among men than women. In most cases, colour deficiency results from genetic factors, specifically from abnormalities or deficiencies in the cone cells in the retina that are responsible for colour perception.

There are three main types of cones in the retina: those sensitive to red light, green light, and blue light. When these cones function normally, the combination of their signals allows people to perceive a wide range of colours. However, if one or more of these cone types are absent, deficient, or malfunctioning, it can result in colour deficiency.

The most common form of colour deficiency is red-green colour blindness. This is characterized by difficulty in distinguishing between red and green objects or shades, and can also involve confusion with orange, yellow, and brown. Other types include blue-yellow colour blindness and total colour blindness (achromatopsia), although these are much rarer.

Colour deficiency can have varying degrees of impact on an individual's daily life. Some people may experience only minor difficulties, while others may face significant challenges in certain situations, such as reading colour-coded maps, distinguishing between traffic lights, or performing certain tasks that rely heavily on colour perception.

There is no cure or permanent treatment for colour deficiency. However, various corrective lenses, contact lenses, or filters may be used to improve colour perception in some individuals.