Many people do not realize that they are color blind, especially children. To confirm this abnormality in vision, color blindness tests need to be done.
Color blindness is a visual disorder. The sufferer cannot see some colors clearly and accurately. They may find it difficult to distinguish some colors, for example red-green, red-yellow-green, or blue-yellow, which is known as partial color blindness.
In addition to having difficulty distinguishing certain colors, some people with color blindness also cannot recognize colors at all or are completely color blind.
Therefore, color blindness test can be used to detect whether a person is color blind or not.
Apart from being carried out as part of a routine eye examination, a color blindness test is also usually required as part of a medical examination before a person applies for a job or study in a particular field.
VariousCauses of Color Blindness
Most people experience color blindness due to genetic disorders or heredity from parents. In addition, this condition can also be caused by:
- Injury
- Chemical exposure
- Optic nerve damage
- Damage to the function of the part of the brain that processes color information
- Certain diseases, such as cataracts, glaucoma, diabetes, or multiple sclerosis
- Age increase
Understanding the Different Types of Color Blindness Test
In the world of work, color blindness tests are important to screen applicants in fields of work that emphasize color perception skills, such as law enforcement, military, engineering, or electronics, to medicine.
Examples of color blindness tests that can be done are:
1. Ishihara Test
This is the most commonly used test to check for color blindness. Unfortunately, the Ishihara test can only detect red-green color blindness.
The Ishihara color blindness test is performed using a card that displays a circle consisting of many dots of different colors and sizes or a specific number.
2. Cambridge color test
The color blindness test is the same as the Ishihara test. The difference is that the patient will be asked to look at the computer screen. While undergoing this color blindness test, the patient will be asked to identify the letter "C" which is a different color from the surrounding colors.
3. Preparation test
In this test, the patient is asked to arrange objects based on slightly different color gradations. An example is arranging blocks from dark blue-blue-light blue gradations.
4. Anomalyoscope
To perform this color blind test, a microscope-like instrument is needed. Through the lens of the device, the patient is asked to see a circle that is divided into 2 colors, half bright yellow and half red and green.
The patient will be asked to press the button on this tool until all the colors in the circle change to the same. Just like the Ishihara test, anomalyoscope can only diagnose red-green color blindness.
5. Farnsworth-Munsell test
This color blindness test uses lots of circles with varying gradations of the same color, just like the arrangement test. The goal is to determine whether the patient can distinguish very subtle color changes.
Those are the various types of color blindness tests that you need to know. If you think you have problems seeing or recognizing colors, consult an ophthalmologist for a color blindness test at a hospital.