Color Blindness (Color Vision Deficiency) is a condition in which certain colors cannot be distinguished, most commonly due to an inherited condition. Red/Green color blindness is by far the most common (99%) form and causes problems in distinguishing reds and greens. Another color deficiency, blue/yellow, also exists but is rare (1%). At this time there is no test universally available for blue/yellow deficiency.
There is no treatment for Color Blindness, nor is it usually the cause of any significant disability. However, it can be very frustrating for individuals affected by it.
Those who are not color blind seem to have the misconception that color blindness means that a color blind person sees only in black and white or shades of gray. While this sort of condition is possible, it is extremely rare.
The Ishihara is a test for color blindness. It was named after its designer, Dr. Shinobu Ishihara (1879-1963), a professor at the University of Tokyo, who first published his tests in 1917. It makes use of the peculiarity that in red-green blindness, blue and yellow appear remarkably bright compared to red and green.
It consists of a number of colored plates, on each plate is printed a circle made of many different sized dots of slightly different colors, spread in a random manner. Within the dot pattern, and differentiated only by color, is a number. What, or even if, a number is visible indicates if and what form of color blindness the viewer has. The full test consists of thirty-eight plates, but the existence of a deficiency is usually clear after fewer plates.
The Ishihara Color Charts are accepted by leading authorities worldwide as a simple and accurate test method. The color plates are available in an album-type book for ease of handling. The books are printed in Japan and are protected by international copy-right. KindCare Medical is an Authorized Distributor of Ishihara Color Blindness Tests.
Color blindness is a common eye condition that makes it difficult to distinguish certain colors. A person that is color blind often experiences problems determining colors like yellow, red, blue or green. Color blindness refers to a deficiency in the way you see color, and not any form of blindness.
This vision impairment mainly occurs among males and is the result of a recessive X-linked gene. Females are the natural transmitter of the color deficient gene but are rarely carriers. Mothers often transmit the deficient gene to their sons but are thus rarely color blind themselves.
Color blindness among females occurs only when the color-deficient gene is passed from father to daughter, if the mother carries the gene as well.
The problem is caused by a cell defect in the retina of the eye. The light absorbing tissue in the back of the eye that transforms what we see into signals to the brain partly contains cells that distinguish colors. When these cells in the retina are not working correctly color blindness occurs.
There is no cure for color blindness and most adults with this vision impairment from birth live without any major discomfort or disadvantages. However, there are cases where additional damage to the retina by aging or disease has led to almost complete color blindness.
Most common symptoms are, like mentioned above, the inability to distinguish common colors like red, green, blue or yellow. If you experience any difficulty in seeing color we recommend you visit your local eye doctor for a proper eye examination. Feel free to test your eyesight in our color blindness online test below to determine your color perception.