Ishihara Test Chart Book for Color Deficiency 24 Plate Edition Manual & Occludar New Ishihara Test Chart Books for Color Deficiency 24 Plates with Eye OCCLUDER  The test consists of a number of colored plates, called Ishihara test plates, each of which contains a circle of dots appearing randomized in color and  size. Within the pattern are dots which form a number or shape clearly visible to those with normal color vision, and invisible, or difficult to see, to  those with a red-green color vision defect, or the other way around. The full test consists of 38 plates, Individuals With Color Vision Defect Should See A Different Figure From Individuals With Normal Color Vision.  Makes Use Of The Peculiarity That In Red-Green Blindness, Blue And Yellow Appear Remarkably Bright Compared With Red And Green  Diagnostic Plates: Intended To Determine The Type Of Color Vision Defect  Ishihara Test Chart Books For Color Deficiency 24 Plates With User Manual