Anomaloscope

An anomaloscope is an instrument used to test for color blindness. It is able to detect whether a person is a dichromat or a tritanope. The apparatus was invented by the German ophthalmologist and physiologist Willibald A. Nagel (1870-1911) who named it "anomaloskop" in 1907.

Note
Anomaloskop Anomaloscópio de Nagel Аномалоскоп