Of course, many met people who do not see, like most, some colors. A similar phenomenon in medicine is called color blindness, or simply the inability to determine correctly one or more colors. Color blindness is partial blindness, expressed in the fact that a person does not see certain colors, most often green, red, yellow and blue.
This disease is congenital, and most often it affects males. To identify it, special tests for color blindness were invented, helping to determine in various ways whether a person has this disease, and if so, in what form.
It is most advisable to pass several tests of varying complexity at once. Let us cite some of them as an example.
The simplest and most affordable color blindness test is an ordinary traffic light. In the event that a person cannot distinguish between a green traffic light and a red one, he is most likely color blind. Moreover, most color blind people are distinguished by red and green traffic signals according to changes in gradation of color brightness. In addition, they know the location of the signals from top to bottom, and therefore problems usually do not arise, however, if you change the location by turning the traffic light over, color blind will be much more difficult to recognize them.
Another simple and fairly reliable test for color blindness is to identify the ability of the test person to distinguish colors used on flags of the countries of the world. Indeed, it is difficult to name the colors of flags from memory, unless, of course, the test person does not deal with heraldry professionally. The essence of this test is as follows: several dozen flags are selected at random and each of them is given a verbal arbitrary color description, and after passing the test, official descriptions and test results are compared. If no serious differences arise, then the test person does not suffer from color blindness.
The most difficult professional test for color blindness is the special test patterns offered to the test person. Similar tests are carried out by experts and reveal, depending on the results obtained, color blindness and its form with the greatest accuracy.
The most popular analogue of such professional checks is the color blindness test, developed by a specialist B. Rabkin, which is carried out according to special polychromatic tables. Each table is a large number of colored circles and dots, which are the same in brightness, but differ in color. A person with normal vision can see images of geometric figures, numbers and letters in such pictures, whereas for a color blind, each picture is just a set of different circles, or he sees completely different figures, and not those that are actually shown.
This color blindness test can be found online at many different sites, and it gives a fairly complete picture, helping to understand whether a person suffers from color blindness.
However, it should be borne in mind that any check at home (not from a specialist) can not give an absolute result, and also will not determine the form of the disease, so if you suspect something is wrong, you should consult an ophthalmologist.
Do not forget that even if the color blindness test is revealed, do not put an end to yourself. This disease refers to those diagnoses with which it is possible to live, moreover, to live comfortably. Moreover, most often color blind people do not even feel any special discomfort from their incorrect color sensation, adjust to their own illness and have the ability to adequately perceive and distinguish most of the colors according to brightness and contrast differences.
True, the presence of color blindness can be a significant obstacle to obtaining a driver’s license.