Colour blindness is an eye condition also known as colour vision deficiency. It is described as the inability to perceive different colours under normal lighting conditions. This condition develops due to the absence of a colour sensitive pigment in the cone cells of the retina which is the nerve layer at the back of the eye. Cones are important since they enable the eye to see and differentiate colours properly. There are three types of cone cells i.e. those sensitive to red, blue or green light, if any of this cells obtain an error colour sightlessness results.

Colour blindness can be inherited; it results when a genetically defective X chromosome is inherited from a carrier mother. The condition can also occur due to an accident or head trauma that causes permanent damage to the eyes’ retina or optic nerve. Retinal damage can also be caused by the shaken baby syndrome. Exposure to ultraviolet rays, certain medications, degenerative diseases like age related macular degeneration and inherited diseases such as diabetes may lead to colour sightlessness.

There three different types of colour blindness that one may experience and they include the following. The red green form which is common; it mainly involves confusion of red and green colours, individuals can obtain it by inheriting a faulty X chromosome gene as a recessive disorder. The red green colour blindness condition is further classified into two. The first one is where different shades of red appear dull and the second one is where colours like green, orange, red and brown appear the same as hue and can only be differentiated by their intensity. The other types are blue yellow colour sightlessness and total colour sightlessness.

Colour blindness caused by eye diseases or medications is treatable. It can be managed via wearing of coloured spectacle lenses or wearing a single red tinted contact lens on the affected eye. While inherited colour sightlessness is not treatable.