Ishihara's Tests for Colour-Blindness / 38 Plates Edition / Kanehara & Co. Ltd 1987 / Hardcover / Made in Japan / Shinobu Ishihara M.D

Hardcover 1987

PAGES: 38 plates and booklet

PUBLISHER: Kanehara & Co

LANGUAGE: English

• ISBN-10: ‎ 0718600800
• ISBN-13: ‎ 978-0718600808 / 9780718600808
  

The Ishihara test is a color perception test for red-green color deficiencies, the first in a class of successful color vision tests called pseudo-isochromatic plates ("PIP"). It was named after its designer, Shinobu Ishihara, a professor at the University of Tokyo, who first published his tests in 1917.

The test consists of a number of Ishihara plates, each of which depicts a solid circle of colored dots appearing randomized in color and size. Within the pattern are dots which form a number or shape clearly visible to those with normal color vision, and invisible, or difficult to see, to those with a red-green color vision defect. Other plates are intentionally designed to reveal numbers only to those with a red-green color vision deficiency, and be invisible to those with normal red-green color vision. The full test consists of 38 plates, but the existence of a severe deficiency is usually apparent after only a few plates. There are also Ishihara tests consisting of 10, 14 or 24 test plates, and plates in some versions ask the viewer to trace a line rather than read a number.

Born in 1879 to a family in Tokyo, Shinobu Ishihara began his education at the Imperial University where he attended on a military scholarship. Ishihara had just completed his graduate studies in ophthalmology in Germany when war broke out in Europe and World War I had begun. While holding a military position related to his field, he was given the task of creating a color blindness test. Ishihara studied existing tests and combined elements of the Stilling test, named after the German ophthalmologist Jakob Stilling, with the concept of pseudo-isochromaticism to produce an improved, more accurate and easier to use tests.