Figure 22. a, the hidden-digit plate of the Ishihara.

Figure 22

a, the hidden-digit plate of the Ishihara. Normal should not see anything, whereas a CVD person should see 5. b, the diagnostic plate of the Ishihara. Normal should see both the 2 and the 6. Deutan-type CVD should see 2 more easily, whereas a protan-type CVD should see the 6 more easily.

From: The Perception of Color

Cover of Webvision
Webvision: The Organization of the Retina and Visual System [Internet].
Kolb H, Fernandez E, Nelson R, editors.
Salt Lake City (UT): University of Utah Health Sciences Center; 1995-.

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