Ishihara color chart

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Principle of the Ishihara tablets in animated black and white illustration

The Ishihara color charts are color charts to reveal red-green visual impairment . They were developed and later named after the Japanese ophthalmologist Shinobu Ishihara , who first described this test in 1917 .

The test is carried out with a disc on which round colored spots of different color nuances and sizes are arranged. Persons with normal color vision can read numbers or letters from it, while test persons with color vision impairment have difficulties or cannot do so by reading out wrong numbers due to the brightness values. Typically, several color tables must be viewed in the test. This makes it possible to estimate the degree of color vision deficiency. About 8-9% of all men (ie about one in eleven) and about 0.5-0.8% of women (about one in 130-200) in western countries have red-green visual impairment ( protanomaly , deuteroanomaly ) affected. Blue-yellow visual impairment ( tritanomaly ), on the other hand, is very rare (less than 1 in 10,000). If it is less pronounced, the red-green visual impairment is practically not noticeable in everyday life and those affected are confronted with it for the first time when looking at the Ishihara tablets. However, certain professions where good eyesight is crucial (e.g. pilot) are not possible for people with significant color vision deficiency.

Ishihara color tablet with the number “74”; Viewers with dichromatic or anomalous trichromatic color perception may read the number as “21” or may not be able to decipher it at all.

  • Color plate 1 ("12")

  • Color plate 11 ("6")

  • Color plate 19 (No number stored; some people with red-green weakness recognize a "2".)

  • Color plate 23 ("42")

See also

Individual evidence

Commons : Ishihara Color Charts  - collection of images, videos and audio files
  1. ↑ Shinobu Ishihara : Tests for Color Blindness. Handaya Hongo Harukich, Tokyo 1917.
  2. ^ William H. Swanson, Jay M. Cohen: Color vision. In: Ophthalmology Clinics of North America. Vol. 16, No. 2, June 2003, ISSN  0896-1549 , pp. 179-203, PMID 12809157 , doi : 10.1016 / S0896-1549% 2803% 2900004-X .
  3. ↑ Maureen Neitz, Jay Neitz: Molecular Genetics of Color Vision and Color Vision Defects. In: Archives of Ophthalmology. Vol. 118, No. 5, May 2000, ISSN  0093-0326 , pp. 691-700, PMID 10815162 , doi: 10.1001 / archopht.118.5.691 .

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