Ishihara color blind test

Color blindness (sometimes referred to as daltonism) is a condition in which a person has difficulty distinguishing specific colors. There are several main types of color blindness: red-green, blue-yellow, and complete color blindness (monochromacy). The red-green type is the most common one; it's when an individual has difficulty identifying colors and shades in the red and green spectrum.

It is a very common issue affecting about 1 in 12 men and 1 in 200 women. The number of people with color vision deficiency worldwide is estimated to be around 300 million.

The Ishihara test is a commonly recognized and widely used color vision test developed by Shinobu Ishihara, a doctor at the University of Tokyo, in 1917. It consists of a set of plates with a pattern of dots of different colors and sizes. The patterns are designed so that the numbers on them are visible to people with normal color vision but not to people with red-green color blindness.

The Ishihara test is a simple and effective way to detect color blindness. It is often used by ophthalmologists as part of an eye test. The original Ishihara test consists of 38 images; this is a short version with 14 plates.

The test must be taken without glasses with colored lenses or sunglasses that distort the perception of colors. If you use color-changing lenses, it is recommended that you also remove them during the test.