Color-blindness is the inability to distinguish the differences between certain colors. This condition results from an absence of color-sensitive pigment in the cone cells of the retina, the nerve layer at the back of the eye. Most color vision problems are inherited and are present at birth. Approximately 1 out of 12 males and 1 out of 20 women are color blind.
A person with color-blindness has trouble seeing red, green, blue, or mixtures of these colors. The most common type is red-green color-blindness, where red and green are seen as the same color.
What problems can it cause?
Many tasks that we do each day rely on us being able to separate things by their colour. If people are not able to see the difference in colour they have to rely on other differences which may be harder to pick.
In the classroom, blocks or other teaching tools may be colour coded as well as being of different size. A child with colour vision problems may have to rely only on size differences alone.
On a computer screen, colour is often used for highlighting important words and the only way some children may know that the words are important is because the shade is slightly lighter or darker.
Some occupational groups will not allow a worker who is colour blind to do certain work (for example where wiring or warning lights are colour coded).
Most everyday things can be done without colour vision being a problem, but some people with colour vision problems say they have some annoying difficulties such as not being able to see whether fruit such as apricots are ripe.
What you can do
All boys should have their colour vision tested when other people in the family are known to have colour vision problems. This testing can be done most easily when a child starts to know numbers (around the time that he starts school) or when he is older. If people on both side of the family are known to have colour vision problems, all the girls should also be tested.
Although it is often recommended that all children (especially boys) have a colour vision check while in the early years of school, this is not available in many places.
In any group of about 20 boys, it is likely that one or two will have a colour vision problem. If, at school, a lot of tasks are colour coded, these boys may have learning difficulties, so it is worth knowing if a child has a colour vision problem, so that ways for him to learn can be found that do not rely on colour.
Colour vision testing can be done by ophthalmologists (eye specialists) and optometrists (opticians) using specially designed charts (including ones called Ishihara colour plates). Some school health services and some doctors will also be able to test children's colour vision.
After a colour vision problem is found, further testing might be needed to tell just exactly what the problem is, because this can affect whether the person will be able to do certain jobs, or be able to get certain types of driving licences.
There are many sites on the Internet which have some colour vision checking charts, but they cannot be relied on like special test charts printed on paper (which have very carefully shaded as well as coloured spots, lines or other objects). It is best to get your children checked face-to-face.
please see your optician for more details.
PTA
