Colour Blindness

What is colour blindness?

Colour (color) blindness also called colour vision deficiency or CVD affects approximately 1 in 12 men (8%) and 1 in 200 women in the world. There are different causes of colour blindness. For the vast majority of people with deficient colour vision the condition is genetic and has been inherited from their mother, who is normally a 'carrier' but not colour blind herself. although some people become colour blind as a result of other diseases such as diabetes and multiple sclerosis or they acquire the condition over time due to the aging process, medication etc.

Most colour blind people are able to see things as clearly as other people but they unable to fully ‘see’ red, green or blue light. There are different types of colour blindness and there are extremely rare cases where people are unable to see any colour at all. The most common form of colour blindness is known as red/green colour blindness and most colour blind people suffer from this. Although known as red/green colour blindness this does not mean sufferers mix up red and green, it means they mix up all colours which have some red or green as part of the whole colour. For example, a red/green colour blind person will confuse a blue and a purple because they can’t ‘see’ the red element of the colour purple. See the example of pink, purple and blue pen cases below to understand this effect.

When we see different colors, we are perceiving differences in the type of light that is reaching our eyes. The way we see different colors is something like the way we hear different sounds as being "low" or "high." This is called pitch, and it corresponds to the frequency of the sound.

The keys on the left side of a piano keyboard make low-frequency sounds, for example, and the frequency of the sound gets higher as one plays keys further to the right. There is a similar order to the colors we see. The colors of every rainbow always appear in the same order: red, orange, yellow, green, blue, and violet. The different colors in each part of the rainbow correspond to a different wavelength of light. Reddish colors are long in wavelength and bluish colors are shorter. And just as there are many notes on the piano, there are many wavelengths of light corresponding to different colors.

If you think you have a problem with color vision, you should schedule an appointment with an eye doctor right away. The doctor will be able to tell you whether you are seeing colors properly and what to do if you are not.

Source :

http://www.colourblindawareness.org

http://my.clevelandclinic.org