Farnsworth test
The Farnsworth test is a test for determining the color vision suitability or color ametropia in humans.
The test is carried out twice with twelve to fourteen differently colored colored plates each, which the person to be tested should place in the order of the color circle . The plates are numbered on the back. The sequence determined in this way by the person is drawn in on a piece of paper on which the correct sequence is arranged in a circle. If the color wheel has been placed correctly, this curve is circular.
If a person sets a different order, the angle of the resulting spikes can be determined on the paper and thus the exact type of color ametropia of this person can be determined. Even the gene sequence that led to this color ametropia can be determined with indirect precision.
The first part of the experiment works with saturated colors and the second part with desaturated colors. The second part serves to determine more precisely anomalies of the color ametropia.
As constant lighting conditions as possible are important for the test, since with mixed light (lighting and daylight) even red-green-blind people are able to correctly set the color wheel depending on the incident light, which is not possible with uniform lighting.