Cone cells are concentrated in the central area of the retina in the macula. Rods detect light and dark whereas cone cells detect colour. In the retina of the eye, there are two types of cells, rods and cones, that detect light.

Often, someone may not be able to distinguish between certain colours, most commonly between reds and greens and occasionally blues. More accurately, it is a colour deficiency rather than colour blindness. What is Colour Blindness?Ĭolor blindness is a term for when someone is unable to see colours in a normal way. Find out everything you need to know about the causes, symptoms, tests and treatment for colour blindness. You may have heard of colour blindness but not really know exactly what it means.