What Is Color Blindness?
Color blindness is also known as color deficiency because someone with color blindness cannot see colors normally. Color blindness is not the same as achromatopsia, where only black, white, and shades of gray can be seen. In order to see colors normally, at least three types of special photoreceptors in the eye, called cones, need to be present. When light is reflected off an object, it enters the eye and hits different types of tiny photoreceptors which then transmits a signal to the brain to tell us what color we see. In color blindness, however, some of these types of photoreceptors are missing or don’t work properly. This means that some colors are not properly seen and that individual is color blind.