Ishihara test

The Ishihara set of coloured dotted plates showing a number or pattern is a useful screening tool for colour defects.

Dr Shinobu Ishihara established the Ishihara Color Vision plate test in 1918. The Ishihara plates are a popular colour vision test in clinics to differentiate colour blind people or types of colour vision deficiency. Red-green types of colour blindness are the most common (Found in 8% of males as is a sex-linked genetic defect). An online test is much less accurate than this, and there are more advanced colour blind tests such as a Nagel anomaloscope which is a “gold standard” reference test for identifying and diagnosing types of red-green colour deficiency.