Ishihara color test

by admin on September 13, 2012



In 1905, Dr. Shinobu Ishihara became a surgeon in the Japanese military Wikipedia Entry . A few years later, however, he shifted his emphasis to ophthalmology, which he researched at the University of Tokyo. By 1910, he was teaching at Japan’s Army Medical College and researching what he called “battlefield ophthalmology.” His goal was to help the army recruit the nation’s most capable soldiers.

A fellow doctor who was colorblind helped Ishihara develop the first charts for what would become the world’s most popular test of color vision deficiency. Known today as the Ishihara Color Test, it began humbly as a series of plates that Ishihara himself hand-painted with watercolors. In accordance with the doctor’s original goal, the test was first used to screen military recruits for color vision abnormalities.

Ishihara published his groundbreaking test in 1917 as a full-fledged University of Tokyo professor. It consisted of circular collections of colored dots of seemingly random sizes. To people with normal vision, one color of dots formed the background while the other formed recognizable symbols. Colorblind test takers would simply see collections of dots; no symbols would be apparent.

A full Ishihara Color Test includes 38 plates; the shorter version contains 24. In fact, it is common for testers to determine a subject’s colorblindness (or lack thereof) after showing just a few plates. The contemporary test features four plate types: transformation (normal and colorblind subjects see different figures), vanishing (only normal subjects see figures), hidden (only colorblind subjects see figures), and diagnostic (plates that help determine the kind and severity of subjects’ colorblindness). Though it is nearly 100 years old, the Ishihara Color Test remains the preferred test for colorblindness around the world.

Several kinds of colorblindness exist; over all, the deficiency is significantly more common in men than in women. Protanopia, which occurs in roughly one percent of men, involves a lack of long-wavelength retinal cones. People with this condition are generally unable to tell green, yellow, and red from one another. In addition, red, orange, and yellow appear unnaturally dimmed.

Individuals with deuteranopia, which also occurs in approximately one percent of men, lack medium-wavelength cones. Green, yellow, and red look the same to them. However, they do not experience an abnormal dimming of these colors. English scientist John Dalton remains perhaps the most famous “deuteranope” in history. Consequently, this deficiency is sometimes called Daltonism.

Test for color blindness


Ishihara’s test for colour-blindness
Category: Equipment
Sub-Category: Colour Vision Test
Designer/inventor: ISHIHARA, Shinobu
Year Of Publication/Manufacture: 1932
Edition: 6th Edition
Time Period: 1900 to 1939
Place Of Publication/Manufacture: Tokyo
Publisher/Manufacturer: T Kanehara and Co
Description Of Item: Original buff cloth cover, 16 standard colour test plates and 6 pp user’s manual in front pocket. Black and white photograph of Dr Ishihra with his signature as frontispiece and spine edges split
Historical Significance: This is an early edition of the famous Ishihara Test. It was first published with Ababic numerals in 1917 and achieved wide-spread recognition in 1929 when it was adopted as an official international test of colour vision by the 13th International Congress of Ophthalmology. This edition was published 3 years later. Shinobu Ishihara (1879 to 1963) graduated in medicine in 1905 on a military scholarship and immediately joined the army as a doctor, serving mainly as a surgeon. He later changed to ophthalmology. In 1908 he returned to Tokyo University where he dedicated himself to ophthalmic research. In 1910 he became an instructor at the Army Medical College. There, in addition to seeing patients, he conducted research on ‘battlefield ophthalmology’ and how to select superior soldiers. In 1912 he went to Germany to further his studies in ophthalmology and in 1915, after the outbreak of war, he returned to Tokyo. There he worked as an instructor in the Military Medical School where he was asked to devise a test to screen military recruits for abnormalities of colour vision. His assistant was a colour blind physician who helped him test the plates. The first charts were hand painted by Ishihara in watercolours using hiragana symbols – the most ‘Japanese’ of the three Japanese scripts. Previous pseudoisochromatic plates existed (eg Stillings) but Ishihara’s plates gave more reliable results. In 1917 he made a set using Arabic numerals called the ‘International Edition’ but few copies were sold. In 1922 Ishihara became a Professor at Tokyo University. In 1929 at the 13th International Congress of Ophthalmology in Holland the International Edition was recommended for testing naval personnel and air force pilots. In 1958 the ‘Law of School Health’ in Japan required that a colour blindness check be done as part of an overall health check on young school children. The Ishihara test was designated as the official test, and it achieved widespread use within Japan. Ishihara’s charts are now the commonest screening test for colour vision anomalies.
V0026602 Shinobu Ishihara. Photograph.

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