Farnsworth Lantern Test has use test
The Farnsworth Lantern Test, or FALANT, is a color vision test originally developed specifically to screen sailors for tasks requiring color vision, such as identifying signal lights at night. It screens for red-green deficiencies, but not the much rarer blue color deficiency.History
The test was developed by Dr. Dean Farnsworth (Commander, United States Navy) while stationed at the Naval Submarine Research Laboratory in New London, Connecticut during World War II.  After its adoption by the United States Navy in 1954 as the standard color vision test for sailors aboard ship, it has additionally been used to screen flying personnel.Test procedure
The test consists of showing a pair of vertically oriented lights consisting of combinations of either red, green or yellow-white.  The test subject is asked to identify the two colors (some of which are identical).  Nine color pairs are administered during the test, beginning with a red/green combination, to allow the patient to see these two colors prior to seeing a white light, which decreases testing errors.  The examinee is shown the target for only two seconds, as color-deficient patients can sometimes correctly identify the colors with prolonged exposure.  The yellow-white light, or one of the identical paired lights, employs a 50% neutral gray filter to reduce luminance cues to the color-deficient patient.  Random presentation reduces memorization of the test sequence by motivated persons.Usage in aviation
The FALANT is accepted by the United States Federal Aviation Administration as a test of color vision for the purpose of obtaining a pilot's license.  However, the United States Air Force discontinued use of the FALANT in 1993 due to its frequent failure to identify cases of color blindness considerably more serious than the test was intended to let pass.
The original FALANT apparatus is no longer manufactured, but many modern equivalents of various levels of sophistication are available today, such as the Optec-900.