Check to see if I have color blindness. Color vision test for drivers
Ophthalmologists are not only high-tech modern equipment on complex software. Old, time-tested methods, such as Rabkin’s tables, turn out to be quite informative.
What are these tables used for, what diagnosis can a doctor make with their help, and why are drivers so afraid of them?
In this article, you will get acquainted with the basics of color testing and will be able to carry out diagnostics yourself online.
What is the technique?
E. B. Rabkin is a Soviet ophthalmologist who devoted his life to the study of such features of visual perception as color perception. To study the perception of colors, scientists have developed a whole range of techniques. Of these, the most popular were the color atlas and tables, which received the name of the author. They make it possible to identify one or another form of color perception disorder and diagnose such a common anomaly as color blindness.
REFERENCE: Color blindness is a congenital vision disorder (“color blindness”) in which a person loses the ability to recognize red and green colors. The disease is named after the English physicist John Dalton, who first drew attention to his own anomalies of “color” vision.
Rabkin's diagnostic method includes 27 test polychromatic pictures. They help determine the presence of a congenital or acquired anomaly of color perception. To clarify the diagnosis, 20 auxiliary pictures are used to eliminate errors during the testing process.
Each of the main 27 tables is a large number of small colored circles on a light field. Their brightness is identical to each other, but the shades and color saturation are different. Circles of one or more similar shades create the outlines of numbers and figures that are easily distinguishable by a person with normal color perception. Patients with color pathology either do not see the given numbers and figures at all, or see completely different silhouettes, distinguishable from the norm.
If, based on the test results, the patient correctly named letters and symbols in all 27 pictures, vision is considered trichromatic. This means that a person is able to accurately distinguish between the three primary colors - red, blue and green. Anomalous trichromasia is indicated by errors in tables ranging from 1 to 12. If a person made mistakes in 12 or more pictures, they are diagnosed with “dichromasia” - the inability to recognize one of the primary colors (most often green).
Indications for use
The polychromatic color blindness test must be taken by all men and women who intend to obtain a driver's license. Correct perception of colors is necessary primarily for safety on the road. And if even experienced drivers do not need to distinguish between shades, then recognizing red, yellow and green traffic lights is vitally important.
A study of vision on color perception is also being carried out among young conscripts. Satisfactory results will be needed by all young people whose line of work will be associated with vehicles.
Trichromatic perception is not a prerequisite for a person to be allowed to drive a car. The results are interpreted individually - even a patient with moderate color blindness can be allowed to drive.
Representatives of certain professions require not only good vision, but also correct color perception:
IMPORTANT! The color perception test can even detect endocrine system disorders. Fluctuations in the level of hormones in the blood, their excess or deficiency can affect the quality of color perception.
In some cases, color sensitivity decreases temporarily. This phenomenon can be caused by motion sickness in transport, mental or physical stress, or taking medications. Such patients are recommended to be tested again as soon as their health returns to normal.
Types of people according to color perception
Based on the criterion of color perception, ophthalmologists divide all patients into three categories: deuteranomalies, protanomalas, tritanomalas. Let's look at each of them in more detail.
Deuteranomaly
Deuteranomaly is a vision condition in which a person has reduced sensitivity to green spectrum waves. Deuteranomaly patients can distinguish light shades well - blue and light green. But in order to fully perceive blue-green tones, such people need high color saturation and a large number of green waves.
The anomaly is diagnosed in only 1% of the population and is associated with the absence of chlorolab in the retina. This special substance is a photosensitive pigment responsible for recognizing the yellow-green range of colors. This type of color blindness is congenital and cannot be treated.
Protanomaly
Protanomaly is a visual disorder associated with difficulties in perceiving shades of the red spectrum. This is also a congenital anomaly, but it is caused by a deficiency of a photopigment such as erythrolab. It is he who has high sensitivity to red waves and allows a person to recognize shades from pink to orange.
Weak degrees of protanomaly are difficult to diagnose and do not affect the quality of life. With a high degree of impairment, the patient either sees very little red tones, or sees gray tones instead.
Tritanomaly
Tritanomaly, or tritanopia, is a perceptual disorder that highlights shades of blue. The disease is directly related to the functioning of the “blue” cones of the retina, which are especially sensitive to short-wave radiation. The disorder is caused by the absence of this type of cones or a deficiency of the pigment responsible for their functioning.
The patient has difficulty distinguishing not only blue and cyan colors, but also all shades of violet. Instead, the human eye sees dark gray or light gray spots. The pathology is considered incurable and occurs with equal frequency in both sexes.
Causes of color blindness
The disease is hereditary, but color perception can also be impaired under the influence of external factors. Congenital color blindness occurs due to chromosome mutations and is transmitted through the maternal line. In this case, the disease most often affects men (2-8%), while in women the disorder occurs only in 0.4% of cases. Patients with color blindness lose the ability to distinguish one or more primary colors, while other vision parameters are within normal limits.
REFERENCE! Acquired color vision disorders include monochromacy. Patients with this diagnosis see the world around them in only one color due to damage to almost all photoreceptors of the retina.
Normally, color perception is built thanks to three types of special receptors in the retina. Each of them contains a corresponding protein pigment responsible for recognizing three basic colors:
Often, “color” cones are affected against the background of pathological processes in the retina:
- mechanical damage;
- age-related macular degeneration;
- diabetic retinopathy;
- degeneration, etc.
There is currently no specific treatment for color blindness. Glasses and lenses with special filters help improve color perception.
Self-diagnosis using pictures
The large pictures below allow you to diagnose your own perception of shades. Each table is accompanied by a brief description of the norm and pathology.
№ 1. This is an introductory picture that allows you to identify malingerers and show how the test works. People with and without disabilities should see a nine and a six here.
№ 2. The principle is the same as in the previous table. A person with any vision should see a circle and a triangle.
№ 3. Pictured here is the nine that trichromats should see. If there is an anomaly in the perception of the red and green spectra, a person will see the number 5.
№ 4. A patient with normal vision should see the triangle shown. Protanomals and deuteranomalies will see a circle in the picture.
№ 5. The table shows the number 13 - one and three. Individuals with red or green spectrum blindness will see a six.
№ 6. The norm is a circle at the top and a triangle at the bottom; with any color pathology, recognition of these figures is impossible.
№ 7. The number nine and six shown in this picture should be clearly distinguishable by healthy people. Colorblind people only see six.
№ 8. The picture shows a five, which patients with the disorder recognize very poorly or do not see at all.
№ 9. Trichromats see the number 9 in the picture, colorblind people perceive it as an eight or six.
№ 10. Three numbers are drawn here that make up the number 136. Protanopes and deuteranopes do not see this number, calling 66, 68, 69 instead.
№ 11. Healthy people see a triangle and a circle in the picture. With an anomaly in the perception of the red spectrum, patients see only a triangle, and in the green spectrum - only a circle.
№ 12. In the picture the patient should see a one and a two. If these numbers do not differ, we can talk about protanomaly.
№ 13. A healthy person should see a triangle and a circle in the table. With protanomaly, the triangle will not be distinguishable, and with deuteranomaly, the circle will be indistinguishable.
№ 14. Normally, the numbers 3 and 0 should be recognized in the upper part of the picture. With red color blindness, a person will see 1 and 0 in the upper part, and a hidden six at the bottom.
№ 15. This table shows a circle (on the left) and a triangle (on the right) - patients should see them normally. Instead, deuteranopes find a triangle at the top left and a square at the bottom. Protanopes see two triangles at the top and a square at the bottom.
№ 16. Trichromats see the depicted numbers 9 and 6. With disorders of red color vision, a person will see only 9, green - only 6.
№ 17. The norm is the outline of a circle and a triangle. Only a circle is a deuteranomaly, only a triangle is a protanomaly.
№ 18. The table consists of alternating rows of red and green colors. With red color blindness, vertical rows Nos. 3, 5, 7 will look monochrome. With green blindness, vertical rows No. 1, 2, 4, 6, 8 will appear monochromatic.
№ 19. Healthy people should be able to discern the number 95 in the table; all colorblind people see only the number 5.
№ 20. A circle and a triangle - this is what a normal picture should look like. Patients with color blindness do not see these figures.
№ 21. People with normal vision should see 6 rows here - vertical in one color and horizontal in different colors. For colorblind people, the opposite is true - the vertical rows will be multi-colored, the horizontal rows will be in the same shade.
№ 22. Persons with normal vision should see two sixes here, colorblind people see only one of them.
№ 23. 36 – this is the number seen by all colorblind people and trichromats. In case of severe color vision impairment, the numbers will not be visible.
№ 24. The test is aimed at identifying acquired pathology of color vision. Such patients will not see the number 14, while healthy individuals, deuteranopes and protanopes recognize it.
№ 25. The principle is the same as in test No. 24, only one number 9 is outlined in the picture.
№ 26. Normal trichromats, protanopes and deuteranopes distinguish the number 4 in the table. Acquired pathologies of color perception do not allow one to see this symbol.
№ 27. Healthy people should see a one and a three here. Colorblind people cannot distinguish between these numbers.
Test procedure
A study of color perception using the Rabkin method is carried out by an ophthalmologist.
For the test results to be reliable, a number of conditions must be met:
- the patient should be in a calm environment and try to relax as much as possible;
- the picture is placed at a distance of 1 meter from the eyes;
- Each table is allowed to be viewed for about 5 seconds.
At the doctor’s command, the subject names what image he sees on each table, and the doctor records the results in the study protocol.
If the verification is carried out online, the conditions should be similar. Only the results are recorded not by the doctor, but by the subject himself, after which he compares the data with those given under each picture.
IMPORTANT! The brightness of the monitor during testing should be high, the screen should not glare and be located opposite light sources. You need to position yourself so that the display is at eye level and a meter away from them.
Some subjects try to find Rabkin tests with answers before visiting a doctor in order to learn them and give “excellent” results in the office. But even hard training at home will not help mislead an experienced doctor. Among all the tables there are special check tables that allow you to identify malingerers. Tint tests also come to the aid of doctors, which many cunning people fail. We should not forget that pictures can be presented to a person randomly, which can confuse even the most confident patient.
An ophthalmologist talks about determining color perception using Rabkin tables:
Anyone concerned about the results of a future color vision test should remember one fact. Some “color” anomalies occur in 50% of the population. Therefore, even a few errors in the Rabkin test are considered normal for drivers and are not a contraindication to driving.
Color blindness (color vision test) - Also known as color blindness, this is a disease that affects the perception of color. This is due to the fact that the eye is missing one of the three pigments, the combination of which gives all the variety of colors. The test comes after a short section of theory. This can be verified using a very common graphic format - RGB, which stands for “Red, Green and Blue”, that is, “red, green and blue”. These same colors are found in our eyes.
Usually, color blindness is caused by genetic changes, which affect the ability to perceive individual colors and their shades. However, Acquired color blindness is also common. It can develop due to diseases affecting the optic nerve or due to injury to the eye. Also, simple age-related changes contribute to the development of such a condition.
It is worth noting that color blindness may be a clear prohibition for certain types of work.
For example, until recently, it was prohibited to drive a vehicle if color vision was impaired. There is a ban on airplane control for colorblind people. This is due to the fact that in the cockpit there are many multi-colored sensors that need to be clearly visible.
However, one hundred percent vision is required not only for pilots, but also for many other professions. For example, this applies to some types of production, as well as for electric train drivers. Particularly stringent requirements for health in general, and for vision in particular, are imposed in the metro, where color vision tests are carried out annually.
What is used for diagnosis
In order to check your color perception, you can get tested by an ophthalmologist. It is quite simple and does not take much time, but it allows you to accurately determine whether you have color weakness. To determine color blindness use Rabkin tables, sometimes called Ryabtsev tables. Typically, this is a book that contains a set of pictures. There are circles of different sizes and colors on them, which make up different numbers or geometric shapes.
Each picture has a certain combination of colors of the same brightness, which will accurately determine whether you have color deficiency. If perception is impaired, a person will see either a jumble of circles, or incorrect symbols, which are also encrypted there. This test also consists of two parts. The first allows you to understand whether there is a vision anomaly, and the second serves as an auxiliary one. In the second part of the test, images are selected that will indicate which color you have problems with perceiving.
In addition, no less popular are Yustova's tables. They allow us to conduct threshold studies of color vision and determine which shades are perceived with the greatest difficulty. This is necessary for a more accurate examination.
However, it is possible to undergo a similar examination on the Internet.
Now there are many sites on which the above tables are posted. Some of the resources offer a survey in the form of a test, where you need to choose one of several answer options. Others lay out tables under which the correct answers are indicated, with explanations.
However, it is worth noting that online testing is not always reliable. This is due to the fact that the monitor is not always correctly adjusted to reproduce colors. In addition, there may be malfunctions in its matrix, which also distorts the perception of colors, and therefore makes the test unreliable. However, with the help of such tests, you can get an idea that something is wrong with your vision, which means it’s time to see a doctor.
Some people, in order to get the desired position, enter queries into a search engine, like "check with answers", in hopes of learning the correct answers to tests. However, with such scams, they expose themselves and others to danger.
If you managed to get a physical copy of the tables, or cards, then you can take the tests yourself. To do this, you should use the following rules: which are also used in the ophthalmologist’s office:
- You should sit with your back to the window, and the tables should be opposite you.
- The distance to the tables should be one meter.
- They should be held at the same level as your eyes, vertically.
- It takes from five to seven seconds to view the image and answer.
It is worth remembering that you should take the test when you are in good health, as illness or fatigue can affect the clarity of your vision. Also, you need to relax before starting testing - nervousness is not the best assistant in this matter.
Color perception test using Rabkin tables
Image No. 1 shows the number “96”, which is visible to both people with normal vision and people with color blindness. The goal is to clearly show the subject what exactly needs to be done when taking the test.
This image shows the shapes - a square and a triangle. These figures are visible to both people with normal vision and people with color blindness. The goal is to demonstrate the test and identify simulation.
This image shows the number "9". If anomalies are present (people with blindness in the red or green part of the spectrum), then the person will distinguish the number “5”.
In this image, people with normal vision will see a figure - a triangle. If an anomaly is present, the person will see a circle.
The image shows the numbers "1" and "3". People with blindness will see the number "6".
People with normal color vision will see two shapes in the image - a triangle and a circle. People with blindness cannot distinguish the figures at all.
The number "9" is hidden in the image. It can be seen by both healthy people and people with color blindness.
The image shows the number "5". Healthy people see it perfectly, but people with color blindness see it with difficulty or do not distinguish it at all.
The image shows the number "9". It is clearly visible to people with normal color vision and people with blindness in the green part of the spectrum. However, people with red blindness may see "8" and "6" in addition to "9".
With normal color vision, people see the number “136”. If there is an anomaly, then the numbers “66”, “68”, “69” are visible.
The image shows the number “14”, which is clearly visible to people with healthy vision and people with color blindness.
The image shows the number "12", which is perfectly visible to people without anomalies and people with blindness in the green part of the spectrum. People with blindness in the red part of the spectrum cannot distinguish these numbers at all.
The image shows the shapes - a triangle and a circle, which are distinguished by people with normal color perception. If blindness is present in the green part of the spectrum, then people see exclusively a triangle. If blindness is present in the red part of the spectrum, then people see only a circle.
The image shows the numbers “3”, “0”, “6”, which are seen by people with healthy vision. If blindness is present in the green part of the spectrum, then the numbers “1” and “6” are visible. If blindness is present in the red part of the spectrum, then the numbers “6”, “1” and “0” are visible.
People with normal vision distinguish a circle and a triangle in the upper part, and sometimes a square in the lower part. If there is blindness in the red spectrum, then the person sees two triangles in the upper part and a square in the lower part. If blindness is present in the green spectrum, then people see a triangle at the top and a square at the bottom.
People with normal vision will see the number “96” in the image. People with red spectrum blindness only see “9.” People with green spectrum blindness only see “6.”
A healthy person will distinguish between the figures - a triangle and a circle. People with red spectrum blindness will only see a triangle. People with green spectrum blindness will only see a circle.
People with normal color perception will see multi-colored vertical and single-color horizontal rows. People with red spectrum blindness will see the horizontal rows as single color and the vertical rows 3,5 and 7 as single color. People with green spectrum blindness will see the horizontal rows as multi-colored, and the vertical rows 1,2,3,6 and 8 as single colors.
People with healthy vision will see the numbers “2” and “5”. People with red or green spectrum blindness will only see the number “5.”
People with healthy vision distinguish between the shapes of a triangle and a circle. People with red or green spectrum blindness cannot distinguish shapes at all.
The image shows the number “96”, which is clearly visible to people with normal color vision and people with red spectrum blindness. People with green spectrum blindness only see the number “6.”
The image shows the number "5", which will be seen by people with normal vision and people with color blindness, but the latter will see it with difficulty.
In this image, people with healthy vision will see multi-colored horizontal rows and single-color vertical rows. People with color blindness will see single-color horizontal and multi-colored vertical rows.
People with normal vision will see the number “2”, people with blindness in the red or green spectrum do not distinguish this number.
People with healthy vision will see two figures - a square and a triangle. If there is an anomaly in color perception, then a person will not be able to distinguish the figures.
People with normal color vision will see a triangle in the image. People with the anomaly will see a circle.
Types of color blindness
There are several types of this disease, which differ in the colors which are difficult to perceive:
- Protanomaly and deuteroanomaly. These are two variants of the disorder in which the perception of the red or green color of the spectrum is impaired. However, there are often cases when both colors are perceived with difficulty by a person. This type of color blindness most often occurs in men.
- Achromatopsia. The most rare deviation. In this case, there is a complete lack of color perception. People with achromatopsia see the world completely in black and white, which explains its second name - monochromasia.
- Tritanomaly. Also, a rare change in color perception. With tritanomaly, there is difficulty in perceiving the blue-violet part of the spectrum. Tritanomaly, like achromatopsia, is observed in both men and women.
- It also occurs in people poor light sensitivity. This results in all colors appearing more faded than they actually are.
How is it treated
Unfortunately, this condition has no cure at this time. The reason for this is that the changes, regardless of their nature, affect receptors deep in the eye, which science cannot replace. However, there are ways to stop the disease and change the way a person perceives the world around him.
At the moment, the most popular solution is the use of glasses with neodymium lenses.
These glasses, which are made using neodymium oxide, allow you to partially correct color perception when it comes to protanomaly and deuteroanomaly.
Although, of course, in the future it is planned to cure changes in color perception. Thus, research has recently begun, the goal of which is to correct color perception using genetic engineering. There are already results from tests conducted on monkeys. Their vision and color perception were improved.
Conclusion
Determining color blindness is a fairly simple task, but it is best left to your doctor. The ophthalmologist may advise the colorblind person to undergo additional tests that will show the cause of the disease. But don't be afraid - This anomaly is too rare. However, if you have it, then there is no need to despair. The life of a colorblind person is not very different from the life of those around him, the difference is minimal. Colorblind, this is not a sentence.
Color blindness can significantly ruin a person's life. This is a genetic damage to the eye that does not affect visual acuity in any way. There are many myths and rumors associated with it. How to test for color blindness and what vision testing methods exist, read our article.
Myth 1
Colorblind people see everything in black and white or do not distinguish between red and green.
This is not entirely true. There are quite a few types of color blindness; they are associated with the absence of pigment in the retina that can distinguish certain colors.
Sometimes these pigments are not enough, a person can distinguish all colors, but they look muted, in pastel colors.
With another type of color blindness, the world before a person’s eyes looks like an old photograph in which blue or green dye was added during printing.
To compensate, people who are color blind are able to distinguish many more colors that appear the same to the normal eye.
Myth 2
Only men are color blind.
This is also not entirely true. About 5% of people on Earth suffer from one degree or another of color blindness. And among them, every tenth is a woman. This is a hereditary condition, if there were people in the family with such a problem, it can be passed on even after several generations.
The pathological gene is associated with the X chromosome and is transmitted from mother to son. If in a family the father is colorblind, and the mother is a carrier of the gene, then the pathology may also be detected in the daughter. Color blindness can also appear in a girl if her paternal grandmother was a carrier of the pathological gene. Since most often only one X chromosome is damaged, women have a spare, healthy one.
People discover most cases of color blindness by chance, during medical examinations.
Myth 3
This is a congenital condition and cannot be contracted.
Under certain circumstances, the retina of the eye is injured, it stops producing pigment, and because of this, a person stops distinguishing colors. Men and women are equally susceptible to this disorder. This can even happen to a child.
Sometimes, when the retina is injured, color blindness develops in only one eye, while the other remains with normal vision.
Temporary color blindness occurs when taking certain medications. If left unchecked, it can permanently damage the retina and become permanent.
Partial deterioration sometimes occurs with age, the process is slow, and the person does not notice the changes.
Myth 4
All dogs are colorblind and see the world in black and white.
Recent research has shown that dogs are guided by color and its intensity and brightness.
It is impossible to determine color blindness by the appearance of the eye - it looks exactly the same as a healthy one. The peculiarity of vision is often paid attention to in childhood, when the child constantly confuses colors, cannot identify the same ones, and so on. In many cases this has no consequences.
Reasons for appearance
There are several reasons for color blindness.
It can be congenital or acquired. Congenital affects mainly boys.
Acquired also occurs for many reasons.
- cataract
With this disease, the lens becomes cloudy, light cannot pass through the cones normally, and color perception is impaired. In this case, only one eye can be problematic, the other remains healthy.
- cone dysfunction
the pigment is located in the cones themselves; if their work is disrupted, it is not produced correctly.
- eye injuries
With minor trauma, color blindness is temporary and does not require treatment. The eye only needs rest. In more complex cases, treatment is required, which will be prescribed by an ophthalmologist. The eye needs complete rest.
- tumors
The growing tumor affects the nerve endings of the eye. This disrupts the passage of the impulse and color perception is impaired. Any tumor should be removed, followed by surgery.
- central nervous system diseases
If color blindness is associated with this problem, it should be treated by a neurologist along with an ophthalmologist. When the cause of the disease is identified and eliminated, color blindness will disappear.
- Parkinson's disease and stroke
With these diseases, the passage of nerve impulses from the brain to the eye, to the photoreceptor cells is blocked, which is why color perception is lost.
- diabetes
- Taking medications
If such a problem arises, you need to inform your doctor, you may be able to change medications or find their analogues.
Acquired color blindness can be present in both eyes, most often it is uneven, maybe even of different types.
Colorblind people and professions
In many cases, color blindness does not affect a person's choice of profession. But there are some where the ability to perfectly distinguish colors plays a key role. For example, drivers, machinists, pilots. They cannot practice medicine; they are unlikely to succeed in the field of interior design or fashion.
It will also be difficult for them in teaching, especially with children - in many cases it is necessary to distinguish between colors.
In general, all professions where you need to be able to distinguish colors, shades and halftones.
This is why various tests are carried out to identify deviations in the ability to distinguish colors.
Testing for color blindness in children
A small child with color vision impairment does not realize that he sees the world a little differently from other people; for him, his vision is natural. There is no point in diagnosing him before he is 3 years old. You can suspect something is wrong based on indirect signs - if the child does not always reach for the brightest toy, but may take a gray and pale one.
Typically, children remember the names of colors by the age of 3-4 years. Find objects of the same color even earlier. But if the baby is color blind, he is physically unable to do this. The parents are angry with him, but the child does not understand the reason.
Most often, the child does not distinguish between red and green, blue and yellow.
If a child has such a visual feature, then first of all you need to calm down. First of all, parents - color blindness is not a disease, the child will simply have to adapt to such vision, and the parents will have to come to terms with this peculiarity of the child.
Parents can check their vision for color blindness even before their child enters school quite simply - by watching how he colors pictures.
If he often gets confused about the colors of the grass or sky, and they look unnatural in his drawings, this could be a warning sign.
Older children are given several plain pieces of colored paper and asked to choose the same color. If the baby finds it difficult, you should definitely consult an ophthalmologist.
For older preschoolers and primary schoolchildren, you can already use the same tests as for adults.
Schoolchildren
For schoolchildren, this problem can cause many difficulties in their studies. What is written on a blackboard with colored chalk often turns out to be invisible and indistinguishable to him. And your own drawings are distinguished by unnatural colors. Teachers should be aware of this feature of their student and help him cope with circumstances beyond his control - for example, he should sit in the classroom so as not to see the glare of light on the board.
If you haven’t encountered a similar problem with your child before school, then elementary school is the time to do it.
For adults, there are other diagnostic methods.
Diagnostic methods
There are many types of color blindness. The easiest one is the inability to distinguish shades of color. For example, dark pink is perceived as red, while lighter tones are seen as white.
Rabkin tables
The most famous and popular diagnosis is using Rabkin tables. They depict many colorful circles of different shapes and sizes. All these circles are of the same brightness, and among them numbers or geometric shapes stand out in a different color.
A person with normal vision can almost easily distinguish them from the rest. If there are violations, these encrypted figures will be indistinguishable to him.
Testing
It happens simply - signs are placed in front of the subject in good, uniform lighting, the patient examines them for a few seconds and says what he sees. In this case, the person should be in a relaxed state and feel good. 7-10 seconds are allotted for viewing one picture; the pictures are located at a distance of 1 meter from the eyes at the same level with them.
These tables also contain trap figures. For example, a person with normal color vision sees 9, and a colorblind person sees 5, or a circle. Only colorblind people with a certain type of colorblindness see them; the doctor, using his tables, will be able to determine which pigment is missing on the retina.
Several pictures in the set were created to identify malingerers, those who for some reason want to deceive the signs when taking the test. These plates depict pictures that are clearly and clearly visible with normal vision and with any form of color blindness. The doctor can easily determine which color the patient cannot distinguish.
The circles on the tables are selected in such a way as to check all possible deviations. And the color combinations in them are not random. However, when taking the test on a healthy person, errors are possible - the result may depend on the computer screen itself and the lighting.
There are 48 plates in the set, 27 are used for general diagnostics. The rest are needed for a more in-depth analysis. They are necessarily included during inspections of professional drivers, machinists, and pilots.
The main Rabkin tables can be purchased, the rest remain for more detailed analysis from a doctor. It is useless for a colorblind person to pretend to have healthy vision; the doctor will decipher it anyway. It is also useless to pretend to be colorblind during military commissions - the remaining plates will still show color perception, it is impossible to learn them.
If these tables show severe color vision impairment, for example, red and green look the same, the person will be denied a license altogether. The same thing will happen if colors in the blue-yellow range are not distinguished.
Testing for color blindness using the Rabkin table is used all over the world; it gives the most reliable result, the type and degree of pathology. And control pictures will clarify the diagnosis.
Yustova's technique
This technique also consists of cards and is designed to identify which color disorder the patient has.
The subject is offered four sets of cards, each of them identifying the pathology of one primary color.
- The first set reveals disturbances in the perception of red and its shades,
- second - green spectrum
- third - blue
- fourth - black and white text
The tables are special pictures with “torn” squares, which depict a stylized letter C, with a break in one of the sides of the square. The subject must determine the location of the rupture.
There are 12 tables of the test, each table shows several pictures with such an image. All cells form one tone, the test is constructed in such a way that the possibility of “learning” it is excluded.
The test is also good because it is easy to conduct with children who do not yet know numbers and geometric shapes.
This test is also popular among ophthalmologists around the world. It is also used in diagnosing acquired color blindness in adults after various injuries, diseases and taking certain medications.
Ishhara test
The test is somewhat reminiscent of Rabkin's tables. In it, the subject is also offered tables consisting of many circles of different colors and sizes. But in it a person must no longer distinguish numbers or letters, but pictures and simple images.
This test is used mainly to diagnose color blindness in children; they like such pictures and willingly guess the encrypted images. These pictures can also be offered to those who have “learned” Rabkin’s tables for “passing a medical examination.” If color blindness is present, a person will not be able to distinguish the desired image.
Some other color blindness tests work in much the same way. These are the color schemes of Stilling, Schaaf, and some others. Their principle is approximately the same.
Special cases
There are special cases when testing vision for color blindness. When more in-depth research is required, and increased demands are placed on the subjects’ ability to distinguish colors.
Not only drivers of any transport need to perceive colors correctly. There are cases where this can be a key point.
Military
When passing a military commission, such a test will be required. With normal visual acuity, you will still be drafted into the army, but you can serve in a very limited number of troops. In any case, it will not be possible to deceive the military registration and enlistment office,
Doctors
All doctors need full color vision. The health of other people depends on this, so doctors regularly check these parameters of their vision.
Chemists
If it is difficult to distinguish colors, then you can use a lot of chemicals. Many solutions differ in appearance only in shade, but the properties of the substances are different. It is better for a colorblind person not to study chemistry professionally.
Treatment of color blindness
How to help a colorblind person see the world in all its fullness? After all, this is especially offensive if the loss of the ability to distinguish colors was acquired as a result of an accident.
Congenital
It is currently impossible to cure congenital, genetically determined color blindness. In order to somehow help a person, multi-colored lenses are selected specifically for his vision. But this method is ineffective and controversial. It may even be dangerous to your overall vision. So while research is being carried out, such contact lenses are not used.
Special glasses with multi-colored lenses have been created, but these are experimental models, they work in certain lighting and cannot be worn for a long time.
Attempts are being made to introduce the missing genes into the retina of the eye - so far only with the help of computer programs on virtual colorblind people. But research in this area is being carried out and, perhaps, a solution to the problem will still be found.
Acquired
Acquired color blindness can be cured. Treatment depends on what caused it.
- If medications are the cause, they should be discontinued; color perception will be restored over time.
- Operative - by eliminating cataracts or other retinal damage
Most often, when acquired color blindness occurs, a person’s visual acuity begins to decline.
Drug treatment is prescribed by a doctor; you cannot prescribe it for yourself - this can result in an irreversible change in vision, which will only get worse, until the complete loss of color vision.
A color blindness test is a procedure that allows you to evaluate impairments in the perception of shades of the color spectrum. This disorder is genetic in nature. A person who is unable to perceive and distinguish certain colors cannot fully see road signs and images. There are a number of professions that are not suitable for a patient with color blindness.
Description of the color blindness test
A test to check color perception is an event that allows you to assess the patient’s ability to distinguish shades of the color spectrum. This may be required when a person enters the service or plans to obtain a driver’s license.
In ophthalmology, the following types of people are distinguished, according to the types of disorders:
- trichromats - individuals who fully perceive and identify all shades of the color spectrum;
- deuteranopes - patients with altered color perception of green. They are unable to distinguish some shades and colors of the blue-green spectrum and shades of yellow-green and purple;
- protanopov. These are patients with impaired color vision in the red spectrum. They do not have a special pigment in the retina of their eyes, which is responsible for sensitivity to the red-orange region of the color spectrum. Protanope distinguishes blue from green and green from deep red.
Color vision impairment cannot be completely cured.
A test to identify color blindness (this is also what color blindness is called) is performed based on a demonstration of Rabkin’s polychromatic tables. They consist of 48 images in which numbers and geometric shapes are “encrypted,” but to diagnose color blindness it is enough to use the first 27 pictures.
Ophthalmologists believe that 8% of the male population worldwide suffers from color blindness. In women, this deviation is detected much less frequently, in only 0.5%.
The need for verification
Impaired color vision does not affect human health, but significantly reduces the quality of life. First of all, color blindness limits the possibility of obtaining a certain profession or qualification.
A color blindness test is carried out to assess the degree of color vision impairment and how different it is from the standard.
This test is prescribed to assess whether a person can engage in a certain profession and drive a vehicle.
Test algorithm for drivers
To obtain a driver's license, a person must pass a color blindness test.
A colorblind person does not have the right to drive a vehicle, since the inability to distinguish colors creates an increased risk of an accident while driving.
To assess the color perception of a potential driver, the ophthalmologist uses color tables (this is the mentioned Rabkin table).
Before the diagnosis begins, the patient must take a position so that the source of artificial light or a window transmitting sunlight is behind his back.
The research is carried out like this:
- pictures with encrypted images are placed vertically, at eye level. The distance from the tables to the eyes is a meter;
- if a person wears lenses or glasses for vision correction, they do not need to be removed during testing;
- the ophthalmologist stands opposite the person being examined;
- the patient examines each picture for 5-7 seconds and then tells the doctor which figure or number he saw. Recognition time should not exceed 10 seconds.
A test with such tables should only be carried out when the potential driver is feeling well.
Tests with answers to check drivers
Potential motorists who want to obtain a driving license for the first time should definitely visit an ophthalmologist to evaluate their visual function.
Some of those who suffer from color anomaly try to “pass” the color blindness test by deception. To do this, they prepare for the study in advance, memorizing the correct answers for each card.
This cannot be done, because a patient with a severe color perception disorder puts not only his own life in danger, but also the lives of other people.
However, there are freely available tests with answers. They list all the correct options in each of the pictures:
| Picture number | Correct answer (numbers or geometric shapes) | Explanations |
| 1 | 96 | This is a sample image: what is depicted on it is fully perceived by trichromats and patients with color vision disorders. The first picture in the table shows how testing will take place. |
| 2 | The numbers are fully perceived by all categories of patients. The purpose of this table is to identify cases of malingering. | |
| 3 | 9 | In the presence of color perception disorders, patients identify the number as 5 |
| 4 | Triangular figure | Colorblind patients see a circle |
| 5 | 13 | Patients with color blindness identify the number as 6 |
| 6 | Shapes: circle and triangle | Persons with impaired color perception do not see any figures in the picture |
| 7 | 9 | The number can be seen by everyone: both people who fully perceive the color spectrum and patients with color blindness |
| 8 | 5 | Colorblind people are unable to see numbers |
| 9 | 9 | If color vision is impaired, they see the numbers 8 or 6 |
| 10 | 1,3, 6 | In patients with color blindness, the answers may be: 6, 68 or 69 |
| 11 | 1 and 4 | The image is equally visible to healthy patients and colorblind patients |
| 12 | 12 | The number will not be seen only by those who have impaired perception of the colors of the red spectrum |
| 13 | Circle and triangle | Only protanopes will see a circle, only a triangle will see deuteranopes |
| 14 | 3 and 0 | Patients with color vision disorders will see the hidden number 6. In addition, protanopes will see the number 10, and deuteranopes will see 1 |
| 15 | Circle and triangle | Protanopes will have an image of two triangles and a square at the bottom of the picture, while deuteranopes will have a triangle at the top and a square at the bottom. |
| 16 | 96 | Protanopes will be able to see only 9, and deuteranopes - 6 |
| 17 | Circle and triangle | Deuteranopes will see only the first of them, protanopes - the second |
| 18 | Horizontal rows with squares are made in the same color, and vertical rows are made in different colors | Deuteranopes will perceive horizontal rows as multi-colored, and vertical rows 1, 2, 4, 6 and 8 as single-colored. Protanopes will have a different picture: it seems to them that all the horizontal rows are the same color, as well as the vertical rows numbered 3, 5 and 7 |
| 19 | 2 and 5 | In color blindness, only the last digit is identified |
| 20 | Circle and triangle | Patients with color vision disorders do not identify any of them |
| 21 | 9 and 6 | Incorrect perception is observed only in deuteranopes: they will see the last digit |
| 22 | 5 | Patients with color blindness, if they can see it, will only have great difficulty |
| 23 | Vertical rows of squares painted in one color and multi-colored horizontal ones | Colorblind people have the following picture: they perceive horizontal rows as one color, and vertical rows as multicolored |
| 24 | 2 | If you are color blind, it is impossible to recognize the number on this card. |
| 25 | 2 | Impaired color perception does not allow image identification |
| 26 | Triangular and square shapes | Colorblind patients are unable to distinguish the depicted figures |
| 27 | Inverted Triangle | With color blindness, patients identify the figure as a circle |
An incorrect answer when checking deviations in the process of color perception can be associated not only with color blindness: this is possible due to improper lighting, color disturbances and monitor matrix (if a person takes the test online, at home).
Rabkin's tables and book for doctors
Ophthalmologists use the methodological guide “Rabkin’s Tables for the Study of Color Sensation.” The book by a Soviet ophthalmologist contains tables for diagnosing color vision, a detailed description of the methodology for studying deviations, and ways to interpret the results obtained.
Interpretation of test results
The diagnostic result for color blindness depends on the number of incorrect answers the patient makes after viewing the pictures.
If all the answers to 27 cards were correct, then there are no violations, and vision is considered trichromatic. In this case, it is assumed that a person can distinguish between 3 primary colors: blue, green and red.
1-12 errors on the test means the patient has abnormal trichromasia. This is a color vision disorder in which the perception of one of the three primary colors is weakened.
There are 3 types of trichromasia, depending on which color is not identifiable:
- tritanomaly (inability to detect blue tones);
- protanomaly (immunity to red tones);
- deuteranomaly (problem in recognizing green tones).
If there are 12 or more errors in the test, a diagnosis of dichromasia is made. This is a condition in which the patient is unable to identify one of the three primary colors. Most often it is green. In this case, a diagnosis of deuteranopia is made. If a person does not recognize the color red, this phenomenon is called protanopia, if blue - tritanopia.
Using Rabkin's images, it is also possible to reveal a person's complete inability to distinguish colors when he perceives the world in black and white and shades of gray. This phenomenon is called monochromasia.
How to take the test
To obtain an accurate result, an ophthalmologist provides the necessary conditions. The color recognition test is performed as follows:
- The screen on which the pictures will be displayed is set to a medium brightness level. Too dark or light levels interfere with obtaining objective data, as they tire the organs of vision;
- To prevent distortion, tables with images are placed exactly at the patient’s eye level. The person’s eyes should be perpendicular to the picture, since the angle of the screen can distort the results;
- give the patient time to study the tables. The optimal time is 5 seconds. During this period, the eyes will not have time to get tired.
After completing the diagnostic procedure, the specialist evaluates the results and determines the deviation.
What to do if color blindness is detected
Genetically acquired color blindness cannot be corrected, but in some cases of acquired color vision impairment, the situation can be corrected through surgery.
The causes of acquired color blindness are:
- Parkinson's disease;
- brain tumor;
- mechanical injuries to eye structures;
- mechanical damage to the back of the head;
- cataract;
- stroke;
- Leber optic neuropathy, genetically determined.
There is no specific method for correcting color blindness. Usually, special lenses with light filters or glasses are prescribed. This method is suitable for minor disturbances in the perception of the color spectrum.
Surgical treatment of color blindness is prescribed only if this deviation occurs against the background of cataracts or glaucoma.
Online tests to detect color blindness
To test vision for color blindness, special programs have been developed that make it possible to evaluate deviations in color perception at home, behind the screen of a computer monitor.
The pictures that need to be recognized are displayed one by one on the monitor. At the end, based on the results of the answers received, the program will give a conclusion.
It should be taken into account that the program may give erroneous results.
Methods for determining abnormalities in children
Children, like adults, are tested for color vision disorders using Rabkin's polychromatic tables. This method is suitable for children aged three years and older.
Yustova method
You can identify a violation in a child’s ability to identify colors using the Yustova method. Tables are also used for diagnostics, but numbers and figures are not encrypted in them.
The test consists of studying 12 tables. Each depicts torn squares.
The patient is required to distinguish points with the least saturated brightness. This method allows you to determine which pigment is missing in the organ of vision.
Yustova's method has no answers; one cannot prepare for this study in advance and thus falsify the results.
Ishihara method
The patient is shown cards with images of circles of the same color with a small diameter, as well as numbers and figures. The patient must determine what exactly is shown on the tables. The method is similar to the diagnosis of color blindness using Rabkin tables.
The diagnostic method allows you to determine deviations in the difference between the shades of the green and red spectrum.
Assessment of color perception using equipment
In diagnostic centers, you can check for abnormalities in a child using a spectroanomaloscope device. This device examines color vision by simultaneously presenting two color fields for comparison using special light filters.
Another method of hardware assessment of color perception in children is electrophysiological. This is a computer diagnostic that detects disturbances in the functioning of the cones of the organs of vision. During the study, the retina is exposed to rays, determining the light sensitivity of the eyes.
Restrictions on professional activities with color blindness
There are a number of professions in which color blindness is unacceptable. The list of prohibited professions includes the following:
- driver;
- chemical industry employee;
- sailor;
- serviceman;
- pilot;
- restorer;
- painter-plasterer
Color blindness tests can detect color blindness in a person. This deviation is not corrected and does not cause life-threatening complications, but it reduces the patient’s quality of life. If you have color blindness, it is prohibited to engage in certain types of professional activities.
Colorblind people are people who cannot distinguish between certain colors. Sometimes it can be one color, for example: red, green or purple. And sometimes (very rarely) several or all - the world looks black and white. Moreover, this is not considered a disease, but a feature of perception.
A person may not even realize that he sees colors differently from others. This can be revealed by chance or with the help of a special picture, which for colorblind people looks different than for a person with normal color perception.
How to identify whether there is a violation of color discrimination?
There are quite a lot of tests to help determine color blindness, but most of them only detect the difference between green and red colors. Among them, Rabkin’s polychromatic tables were recognized as the most perfect. With their help, you can determine both the type of color blindness and the state of a person’s color perception.
Tests from the Rabkin table are pictures with circles of a certain color scheme and numbers or figures hidden among them. A person with normal color perception sees the “filling” immediately, but colorblind people need to try to see it. In some cases, attempts may not be successful.
Below is a table containing pictures to check. To pass the test, you need to look at them all and see what is depicted on them. Tests are carried out in normal daylight at a distance of 1 m from the table. In this case, the pictures cannot be turned over; they must be vertical, i.e. they cannot be viewed, even if they are on a table or tilted. This may affect the accuracy of the result. After the table, the correct answers will be presented (they are arranged in accordance with the arrangement of the pictures) for comparison with your own.
You need to look at each test (picture) for no longer than 5 seconds (click on the picture to enlarge it):
Now let’s compare the results with the correct answers:
If there are too many incorrect answers, this may indicate severe color blindness.
Korean designers have proposed improving traffic lights to allow colorblind people to drive. They suggest changing its shape. Namely: red – triangle, green – square, yellow – circle.
Interpretation of test results
To understand which colorblind people you can classify yourself as, let’s briefly consider the types of colorblindness. If we talk about a slight violation of color perception - trichromasia, then it can be divided into the following types:
- Deuteranomaly is a violation of the perception of the color green (it is mixed with a light pink or light orange tint).
- Protanomaly is an incorrect perception of the color red (it is mixed with a light brown or light green tint).
- Tritanomaly - inability to distinguish blue-violet colors (they are seen as red or green; rare).
If we talk about more serious violations (distinguishing only two colors), then these are:
- Deuteranopia - everything appears green.
- Protanopia - everything appears red.
- Tritanopia - the world around you is seen in blue shades.
Another type of color vision disorder is monochromasia. This is when everything is seen in black and white. But this phenomenon, like tritanopia, is very rare (1 in 300 cases of color blindness).
Well, now we can begin to interpret the results obtained. Let's look at the example of several pictures to see what seeing/not seeing what is drawn there can mean.
Do you see the number 96 in this picture? No? Do not try to deceive anyone, this is a control test used to identify malingerers. They are visible to absolutely everyone: 
What can you see here? The correct answer to the test is 13. If the number 6 is seen, then this may indicate protanopia or deuteranopia. 
Normally, you need to see the number 96 here. With color blindness, only the number 6 is visible. 
This test is with the number 136. Numbers 68, 69 or 66 may indicate color blindness. 
The norm is a circle and a triangle. Protanopes will see only the second figure here, deuteranopes will see a circle (but they can also see both figures). 
A person with normal color vision will see two numbers at the top of the table - 3 and 0. With protanopia - 1 and 0 at the top, 1 at the bottom (normally not visible), with deuteranopia - 1 at the top, 6 at the bottom. 
If the result is not happy, then do not panic. Since the correctness of answers may depend on lighting, monitor resolution, viewing distance, etc.
Video test for color blindness “Test yourself!”:
The tests presented are approximate and cannot form the basis for independent diagnosis. Only an ophthalmologist can accurately determine the type and condition of color blindness by testing according to all the rules, or after checking with an anomaloscope.
Have you compared your answers with the correct ones? What did you do! Write about it in the comments!
