Purpose:Test class for color blindness, and demonstrate how color blind people with certain defects see the color blindness tests.
Description:Clicking on any of the images above will bring up a full-screen version. In a class the color blindness test patterns are viewed using a video projector using a computer and this web page. If you click your mouse on one of the three patterns pictured above you will see a larger version of the pattern. Clicking on that pattern, you will see another copy of the same pattern with the red removed, that should look similar to the way it would appear to a person with red-green color blindness.
By switching out one of the three (red, blue, or green) projector colors using the included switch box we can see how that particular color blindness test looks to an individual with that type of color blindness. In the first image, the number 12 is visible to all people, including those with any type of color blindness. The middle image appears as a number "15" to those with normal vision, a "17" to those with red-green deficiencies, and no number is visible to those with total color blindness. The rightmost image appears as a number "74" to those with normal vision, a number "21" to those with red-green deficiencies, and no number is visible to those with total color blindness.