Without the L-cones, the eyes have trouble differentiating between green and red. The different forms of color blindness, which include protan color blindness, can range from mild to severe.

Some types of color vision deficiency are so mild that people do not notice any differences between their vision and someone else’s. However, a person with deuteranopia will have red-blue vision ...

It’s also possible for symptoms of deuteranopia to be so mild that you don’t even know about it until you have an eye exam. Symptoms of red-green color blindness may include difficulty seeing ...

The 6-year-old has a mild form of color blindness ... have trouble telling the difference between certain color categories such as red-green or blue-yellow. In rare cases, they may have a complete ...

The report, published in the journal Drug Science, Policy and Law, details the experiences of a 35-year-old man who had been diagnosed with a mild case of red-green color blindness five years earlier.