Wain Ladder

The Wain Dichroic Ladder was developed in 1959 and based on the Wilson Test. The intention of the test was to be more sensitive than the Ishihara Test, thereby detecting even “color weak” color normals. It was never used clinically.

In the test, subjects must match the color of 4 woolen floaters to a spot on 4 separate color scales. Illuminants of different temperatures were used to expand the coverage of the test (Wain 1960).