Colour blindness

Colour blindness (or color blindness in American English) is a condition that affects an individual's ability to perceive or distinguish certain colours. This condition is often inherited and affects more males than females. Colour blindness is also known as colour vision deficiency (CVD).

Types of Colour Blindness

There are several types of colour blindness, each affecting the perception of different colours. The most common types are:

• Protanopia: This is a type of red-green colour blindness where the red cones in the eye are absent, causing red to appear as black.

• Deuteranopia: This is another type of red-green colour blindness where the green cones are absent, causing green to appear as beige.

• Tritanopia: This is a type of blue-yellow colour blindness where the blue cones are absent, causing blue to appear as green and yellow as violet or light grey.

Causes

Colour blindness is usually inherited and is present at birth. It is caused by abnormal photopigments found in the cone cells in the retina of the eye. Other causes can include certain diseases or medications, or aging.

Diagnosis

Colour blindness is usually diagnosed using a Ishihara test, which consists of plates with dots of different colours and sizes that form a number or shape.

Treatment

There is currently no cure for inherited colour blindness. However, special glasses and contact lenses can help people with colour blindness to perceive colours more accurately.

Impact

Colour blindness can impact a person's daily life, affecting tasks such as driving, cooking, and choosing clothing. It can also limit career choices, as certain jobs require accurate colour perception.

See Also

• Visual impairment
• Eye disease
• Genetic disorder