When a person cannot see the colors naturally, the condition is known as color blindness. This happens when a person is not able to distinguish between two colors, usually red, green and sometimes blue. Color blindness is also known as color deficiency.
The retina in our eye contains two types of cells called rods and cones which help us to detect light. Darkness and brightness are detected by rod cells and are sensitive to low light conditions. Cones, on the other side detect colors and three types of cones are present in our eyes which help us to see color. They are red, blue and green. Color perception is determined by this type of cone cells with the help of our brain.
Color blindness occurs when one or more cone cells do not work properly or detect any other color. The condition becomes severe when the three cone cells are not present and a slight color blindness happens when one of the three cone cells do not work properly or detect a different color.
The degree of color blindness differs from person to person. People having mild color blindness have difficulty seeing in low light, but can see normally in good lighting conditions. Some are unable to distinguish between different colors. Usually both the eyes get affected by color blindness. Some people suffer from an uncommon form of color blindness in which they see everything in shades of grey, but this is a rare condition. One can get color blindness at any stage of life. If you think that you have a change in vision consult your ophthalmologist immediately.