Ishihara Color Blindness Test
This test helps identify red-green color blindness. The test consists of showing plates with colored dots that form numbers or shapes.
Test Instructions
- Ensure you are in a room with normal lighting.
- You should be about 75 centimeters (30 inches) from the screen.
- Each plate contains a number formed by colored dots.
- Enter the number you see in the input field and click “Submit”.
- If you cannot see any number, leave the field blank and submit.
- There are 10 plates in this test.
Test Results
What is Ishihara Test
The Ishihara Color Blindness Test is one of the most widely used tests worldwide to detect color vision deficiencies, especially red-green color blindness. It consists of 38 plates, each filled with dots of varying sizes and colors. These dots are arranged in patterns that form numbers or shapes, which can be clearly seen by individuals with normal color vision.
People with color vision deficiency may not be able to recognize the numbers or figures on certain Ishihara plates. Interestingly, some plates are designed so that only individuals with color blindness can see the figures, while those with normal vision cannot.
The standard Ishihara test usually includes 36 plates, though versions with 10, 14, or 24 plates are also available.
Types of colored plates in the Ishihara test
- Demonstration Plate – The first plate in the Ishihara Test is known as the demonstration plate. It typically shows the number ‘12’ (sometimes ‘16’) and is designed so that both individuals with normal vision and those with color vision deficiency can see it. This plate is only used for demonstration and is not counted in the scoring process during screening.
- Transformation plates – People with normal color vision can clearly identify the figures or numbers on the plates, while those with color vision deficiency may see them differently or not at all.
- Vanishing plates – These plates are designed so that only people with normal color vision can see the numbers or figures. Individuals with color vision deficiency are unable to detect them.
- Hidden digit plates – These plates are designed so that only individuals with color vision deficiency can see the numbers or figures, while those with normal vision cannot.
- Diagnostic plates – These plates are used to identify the type of color vision deficiency, such as protanopia (red deficiency) or deuteranopia (green deficiency), and to determine its severity.