Screening
Screening
Colour vision test to check your sense of colour
If colour blindness or colour vision problems are suspected, a colour vision test should be taken in order to avoid dangerous situations, such as in traffic.
In the case of true colour blindness, you hardly see any colours, but rather variations of light and dark. Fortunately, this condition is very rare. Colloquially speaking, colour blindness is used to refer to a red–green impairment, which means those affected can only differentiate between the colours red and green with great difficulty, if at all. Visual colour impairments are usually inherited, but can also be triggered by illness, medication or intoxication.
When are colour vision impairments dangerous?
Healthy sensory cells (cones) in the retina register the different wavelengths of light (red, green, blue violet) and thereby recognise 160 different shades of colour. If the visual impairment is hereditary and/or present in the family, early examination is sensible. Otherwise, the impairment only becomes noticeable in important situations (traffic lights), where the colours are not recognised. There is currently however no therapy for colour impairments or colour blindness.
The Ishihara test
It is easy to find out whether you are colour-blind using the Ishihara test.