We use below tools or tests to check color vision deficiency.
The Farnsworth Lantern Test is a test to diagnose color blindness by signaling pairs of red, green, yellow or white dotted lights.
The test was designed by Dr. Paul H Farnsworth in 1954, to screen for color blindness in the sailors and pilots during world war 2. This was done to test the eyesight of the drivers during signaling at night.
Lantern Test is the best diagnostic test for red-green colorblindness. Since, it uses primarily the red, green, white and yellow colors. It is also called the FALANT test in short.
Here's a step-by-step breakout to perform the FALANT test.
The questions are asked in the following manner as elaborated.
For example,
Example 1- up: red, down: green
Example 2 - up: red, down: yellow.
The online Farnsworth Lantern Test is an accurate test to diagnose red-green color blindness. The test uses the three colors of any signal, i.e., red, green and yellow to check the specific color vision deficiency.
Any misrecognition in any one of the colors of the 9 pairs will be displayed in the result. Hence, the type of color vision deficiency can be diagnosed.
A black background is chosen on which the signals are blinked for a few seconds, thus the accurate color visual and reflexive actions are tested in the Lantern Test.
Though, it is an accurate test to test for red-green color blindness, but is not the best test for colorblindness. This is because it checks for only three colors while excluding the blue color and shades of colors.
Color blinds can sometimes guess the color in the lantern test by recognising the brightness or dimness of the color. For example, red may be viewed as the darkest and yellow the dimest color. Hence, there are some limitations to the test.
If you doubt or you are colorblind and need to pass the test, here are some ways that might help you.
Most of the time, the test will show the same sets of questions in a fixed series, you just need to memorize the series of answers by analyzing the results over and over. And this way, you will pass the test.
For example, the first question contains
Up: Red and Down: Green.
This trick is successful for some color blinds, who practice this in their daily lives. Guessing the color can be risky but is possible by practicing and memorizing how a different color looks to you. For example, red may look darker for you than yellow, yellow darker than white and so on.
This is a cheat to pass the color blind test. This tip shall not make you feel guilty if you continue to use the aids for color blindness for the work that you seek to pass the test for. If it makes your life easy, and you are comfortable wearing it, it is a part of your life. And it can be used for your work and to pass the test as well.
Being a colorblind, the Farnsworth Lantern Test shall be taken by the people employed in the industries related to encounters with colors and colored signals. Here are some of the examples regarding who shall take the test.
It is important for job seekers, applicants and employees to be ready for the overall medical checkup before or after getting hired by the companies, especially those involving color-related work.
Screening tests for being medically and visually fit are on trend across industries for ensuring the growth of the companies. Such companies hire excellent human resources which might prove an asset for the industries.
Thus, the Farnsworth test is used as a screening test for colorblindness in employees to ensure that they are good at handling colors and signals.
Pilots have the most important responsibility of carrying passengers safely during their travel. Air traffic signals, radars, and color signals at night are indivisible portions of a pilot's life.
Pilots require good color vision for dealing with such situations while driving. Hence, most countries have made visual screening tests, especially the Farnsworth Lantern mandatory to screen for color blindness in pilots and personnel from the air traffic controls.
These tests are most important because one misinterpreted signal by the traffic controllers or pilot may cost the lives of several passengers and crew onboard.
Personnel from the military and law enforcement departments need to be alert about their surroundings. Enemies and imposters can attack from any direction by taking a chance from the slightest distraction.
Hence, these personnel need to be apt in their color visual skills to spot the slightest difference in or during the camouflage. They need to keep an eye on the signals from the Allies regarding the next step.
Many operations involve the usage of different colored lighting signals in the sky, the use of radar systems to spot enemies, and camouflage techniques. To ace these conditions, color vision tests are a must to screen and employ the best defenders of the country.
Because a small mistake by any one of the team members can cost the lives of thousands of innocent citizens.
People from the life-saving sectors need to be prompt with their diagnosis and early treatment. Many times, patients are unable to describe their conditions in an emergency or in general. In such situations, our body always gives certain signs of the disease from which it suffers.
A good medical professional has the sight of an eagle to catch the signs. These signs are often interpreted by colors. For example, cyanosis (blue), pallor (white), erythema (red), jaundice(yellow), etc.
And to detect these colors, good color vision is important for healthcare professionals. Hence, such healthcare professionals shall be checked for their color vision to save lives.
It is difficult to be and perform the duty of a pilot, but you can surely become one under certain terms and conditions applied. A pilot deals with the signals and lights of red, green, yellow, white and blue at almost all times coming from the runway, skyscrapers, airport signals, air traffic controls, and most importantly the driving dashboard and radars.
There's no way you can bypass your encounter with these colors. You need to deal with these colors at all points in time. It may be challenging if you are colorblind but it isn't an impossible task.
Flying during the daytime won't cause many issues as you may differentiate or spot the colors based on the darkness or lightness differences among other colors. The real problem may come at night when there's all darkness and you need to focus to your fullest to spot the tiniest speck of a signal.
It may become easier when you have a co-pilot, but it can get difficult to handle in emergencies. For such instances, if you want to survive as a color-blind pilot, you must be prepared with your color blindness glasses, lenses or assistance.
Passing this test does not always mean giving all nine answers hundred percent correct. The minimum criteria for passing the test is to pass with less than three errors in the second or third round of the test.
This means you may have more than three errors in the first round of the test, but you shall decrease your errors to less than three in the subsequent rounds to pass the test.