Vanishing design: Only people with good color vision can see the sign. If you are colorblind you won't see anything.
Transformation design: Color blind people will see a different sign than people with no color vision handicap.
Hidden digit design: Only colorblind people are able to spot the sign. If you have perfect color vision, you won't be able to see it.
Classification design: This is used to differentiate between red- and green-blind persons. The vanishing design is used on either side of the plate, one side for deutan defects an the other for protans.
Description
Ishihara Test Chart Books for Color Deficiency 38 Plates Latest Edition with User Manual and One Eye Occluder by KASHSURG
