color vision deficiency

Commonly called color blindness.

Color vision deficiency is a rare condition affecting mostly men. It can be inherited, caused by disease, or by injury. There are multiple types:

• Deuteranomaly – a red-green color vision deficiency, in which shades of green look more red. This is the most common and is usually mild.
• Protanomaly – a red-green color vision deficiency that makes certain shades of red look more green and less bright. This type is mild.
• Protanopia – a red-green color vision deficiency in which someone cannot differentiate between red and green.
• Deuteranopia – a red-green color vision deficiency in which someone cannot differentiate between red and green.
• Tritanomaly – a blue-yellow color vision deficiency disrupting differentiation between blue and green and between yellow and red.
• Tritanopia – a blue-yellow color vision deficiency disrupting the distinction between blue and green, purple and red, and yellow and pink. It also makes colors look less bright.
• Monochromacy or achromatopsia – these rare conditions cause complete color vision deficiency in which a person cannot see colors. Depending on the type, a person may also have trouble seeing clearly and may be more sensitive to light.

Refer to as color vision deficiency, color vision disorder, or by the specific type with an explanation.

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