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Types of Color Vision Deficiency

Having color vision deficiency (also called color blindness) means you can’t see certain colors the way most people do — or you may not see color at all.

Different types of color vision deficiency cause problems with seeing different colors.

Red-green color vision deficiency

The most common type of color vision deficiency makes it hard to tell the difference between red and green.

There are 4 types of red-green color vision deficiency:

  • Deuteranomaly is the most common type of red-green color vision deficiency. It makes certain shades of green look more red. This type is mild and doesn’t usually get in the way of normal activities.
  • Protanomaly makes certain shades of red look more green and less bright. This type is mild and usually doesn’t get in the way of normal activities.
  • Protanopia and deuteranopia both make someone unable to tell the difference between red and green at all.

Blue-yellow color vision deficiency

This less-common type of color vision deficiency makes it hard to tell the difference between several different color combinations.

There are 2 types of blue-yellow color vision deficiency:

  • Tritanomaly makes it hard to tell the difference between blue and green and between yellow and red.
  • Tritanopia makes someone unable to tell the difference between blue and green, purple and red, and yellow and pink. It also makes colors look less bright.

Complete color vision deficiency

If you have complete color vision deficiency, you can’t see colors at all. This is also called monochromacy or achromatopsia, and it’s rare. Depending on the type, you may also have trouble seeing clearly, and you may be more sensitive to light.

Last updated: August 7, 2023