Understanding Color Vision Deficiencies
Human beings see color the way we perceive tastes. Our taste buds can differentiate between four different tastes- sour, bitter, sweet and salty. In the same way, whenever we look at anything, our visual nerves register the different colors according to their attributes like the brightness and the amount of green, red, yellow or blue present.
The Role of Our Eyes in Registering Colors
Our eyes are quite like television cameras since they are capable to focus and self clean. Whenever our eyes see anything, the exterior light is automatically focused by our lens on the retina. The pigments present in the cells which are light sensitive then absorb the light. These cells are cylindrical in shape like rods and shaped like cones.
Animals generally have two different types of cones while human beings have 3 types of cones. However, eyes are not always perfect. In some cases, the image might not be focused on the retina and instead might be imaged into the blur circle which is a diffuse area. With ageing, the chromatic aberrations that occur could cause colored fringes. This can make the eyes turn yellow with time.
However, eyes can compensate for their flaws on their own. The nerve cells can compare the signals of the cones and measure the amount of red, green, yellow and blue of the image through the edges. On an average, a person would have 6 million cones in the retina. The retina is the layer which is located at the back of the eyes. These cones are all brightness sensitive. In human beings, the three cones are sensitive to long, medium and short wavelengths.
Color Blindness
Quite a lot of people suffer from color vision disorder. If a person is unable to distinguish one color from another, he/she would be color blind. This condition is caused when the pigments are absent in the cone cells of the retina which are color sensitive. Quite a lot of disorders are congenital or inherited. One in 20 women and one in 12 men suffer from color blindness.
Characteristics of Color Blind People
Any individual who is color blind would have difficulty in differentiating between red, blue, green and the mixtures of these basic colors. In the most basic type of color blindness, the individual might have difficulty in distinguishing between green and red colors.
There are a few medical tests available today for this disorder. Consulting a medical expert is the best thing to learn about this disorder.