1. 99% of all colourblind people are not really colour blind but colour deficient; the term colour.
  2. Red-green colour blindness is a combination of red-blindness (protan defects) and green-blindness (deutan defects).
  3. Colour blindness is more prevalent among males than females, because the most common form of colour vision deficiency is encoded on the X sex chromosome.
  4. “What colour is this?” is the most annoying question you can ask your colourblind friend.
  5. There are three main types of colour vision deficiency: protan, deutan, and tritan defects.
  6. Strongly colourblind people might only be able to tell about 20 hues apart from each other, with normal colour vision this number raises to more than 100 different hues.
  7. Iro lenses or glasses can improve colour discrimination in your problem areas but can not give you back normal colour vision.
  8. Ishihara plates are the best-known colour blindness tests, but they are not the most accurate ones.
  9. About 8% of all men have some form of colour vision deficiency.
  10. Severity of colour blindness is usually divided into the following four categories: mild, moderate, strong, and absolute.
  11. The terms protan, deutan, and tritan are Greek and translate to first, second, and third.
  12. A father can’t pass his red-green colour blindness on to his sons.
  13. Dogs are not colourblind.
  14. Colour vision deficiency would be a much better term, but it is not as easy to pronounce compared to colour blindness.
  15. There are people which are really suffering from complete colour blindness, which is called achromatopsia or monochromacy.
  16. Blue-yellow colour blindness would be better called blue-green colour blindness, as these are the problem colours.
  17. There exists every nuance of colour vision deficiency severity, starting from almost normal colour vision up to complete colour blindness.
  18. Protanopia, deuteranopia, and tritanopia are types of dichromacy, which means you have only two different colour receptors (cones) compared to three with normal colour vision.
  19. If a woman is red-green colourblind, all her sons will also be colourblind.
  20. Colourblind people can feel handicapped in everyday life, and almost nobody recognizes this.
  21. 95% of all colourblind people are suffering from red-green colour blindness.
  22. Colour correcting lenses change the light spectrum which stimulates the cones to send different signals to the brain’s vision processing region known as the Occipital Cortex.
  23. Red-green colour blindness is a recessive sex linked trait, which causes more men to be colourblind than women. (8% males. 0.5% Females)
  24. John Dalton wrote the first known scientific paper regarding colour blindness and he made the hereditary connection. So named Daltonism for many years.
  25. Protanomaly, deuteranomaly, and tritanomaly are types of anomalous trichromacy, which means you have three different colour receptors (cones) like people with normal colour vision but one of them is shifted in its peak.
  26. In certain countries you need normal colour vision to get a drivers license.
  27. Deuteranomaly—one form of red-green colour blindness—is by far the most common form of colour blindness.
  28. More women than men are carriers of colour blindness, even though they are not colourblind themselves.
  29. Some people get rejected from a job assignment because of their colour vision deficiency.
  30. About 0.5% of all women are suffering from colour blindness.
  31. Blue-yellow colour blindness is a dominant, not sex linked trait, which means both men and women are equally affected.
  32. Red-green colour blindness doesn’t mean that you are only mixing up red and green colours, but the whole colour spectrum can cause you problems.
  33. The anomaloscope is the most accurate colour blindness test known today.
  34. Police officers, firefighter, and airline pilot are the most famous jobs which require normal colour vision in some countries.

  1. There is no cure for colour blindness. (iRo lenses significantly decrease colour confusion )
  2. Pseudoisochromatic plates were introduced by Professor J. Stilling of Strassburg in 1883; the Ishihara plates by Dr. Shinobu Ishihara followed almost half a century later.
  3. Different chromosomes are involved as sources for the different types of colour vision deficiency.
  4. Knowing when meat is cooked is difficult for anyone with colour vision deficiency
  5. Monochromacy—also called achromatopsia—means you have only one type of colour receptor (cones) in your eyes.
  6. Colour blindness is also called Daltonism, after the scientist John Dalton.
  7. The most often used types of colour blindness tests are: pseudoisochromatic plates, arrangement test, and the anomaloscope.
  8. Better colour vision deficiency terms would be: red-blindness for protanopia, red-weakness for protanomaly, green-blindness for deuteranopia, green-weakness for deuteranomaly, blue-blindness for tritanopia, and blue-weakness for tritanomaly.
  9. John Dalton believed his whole life that the cause of his colour blindness is a coloured fluid inside his eyeballs.
  10. Many colourblind people have problems with matching clothes and buying ripe tomatoes.
  11. Quite a lot of people with normal colour vision can’t pass an Ishihara plates test free of errors.
  12. The International Colour Vision Society is scientifically investigating every aspect of colour vision and colour vision deficiency.
  13. Confusion lines of the CIE 1931 colour space show exactly the colours of confusion for all forms of colour blindness.
  14. Only a whole battery of colour vision tests can reveal the true type and severity of your colour vision deficiency.
  15. John Dalton was also colourblind himself.
  16. Iro lenses work for 95% of colour vision deficient people.


Source: https://www.color-blindness.com/50-facts-about-color-blindness/