Color Blindness

What is Color Blindness?
Color blindness means that you have trouble seeing some colors.
Those colors are: red, blue and green, or mix of these colors. It's rare that a person can't see color at all.
Color blindness is also called a color vision problem. This problem can change your life, first of all it's harder to read and learn, and you can also have problems with certain careers.
Color blindness is not a form at all, but it changes the way you see...
It's very specific, because is not that usual disease.
Picture of the Human Eye
Picture of the Human Eye

Human eye

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This is how Human eye look like when
somebody have color blindness.

What are causes of Color Blindness?

Most color vision problems are genetic and are present at birth. People have three types of cone cells in their eye. Each type senses either green, red or blue. Most cone cells are found in the macula which is the central part of the retina. When you see color your cone cells sense different amounts of three basic colors. Inherited or genetic color blindness occurs when one of the cone cells are not working properly. Other causes besides genetic that cause color blindness are:
  • Aging, glaucoma, macular degeneration, cataracts or diabetic retinopathy.
  • An injury to your eye.
  • Side effects from some medicines can cause color blindness.

What are the symptoms?

  • You can see many colors, so you may not know that you can see colors differently than others.
  • In rare cases, you may see only black, white and gray.
  • While most people can see a lot of different colors, you may see only a few shades of color.

What are the treatments for color blindness?

You first should be tested for color blindness. There are two ways a doctor can test you to see if you have color blindness.
  • Sets of colored dots can be arranged to find a pattern. The patterns that a person can see tells the doctor what color you are having problems seeing.
  • Arranged colored chips in order of simularity of each version fo color that a person is seeing. This also will show the doctor what color the person may or may not be seeing.
Default ImageReady swatches
Default ImageReady swatches
Unfortunately, there is no cure for color blindness; inherited color blindess cannot be corrected. Depending on each situation, some color blindness may be restored.
  • Patients with cataracts can choose to have corrective eye surgery to remove the cataract from over the eye to restore color and blurred vision.
You can compensate for a color blindness problem by purchasing;
  • Special tinted contact lenses and eyeglasses that way a person can define between the colors. The downside of these lenses are that they do not provide normal color vision and can distort objects.
  • Glasses that block glare with side shields can define colors better. When glare or brightness is toned down, a person with color blindness can actually see better when the lighting is not so bright.
  • If a person is totally color blind, then wearing tinted or extremely dark glasses with the side shields can make a clearer and sharper image for that person to see.

Professors at Universities of Washington and of Florida have discovered a cure in two monkeys for color blindness. Professor William Hauswirth, University of Florida can cure a cone diseased primate safe and effectly. "Its extremely encouraging for the develpment of theraties for human cone disease that is really blinding."
The treatment was done by injecting a virus that contained the L opsin gene into the retina of the monkey. After a few weeks the monkey could easily distingush the patterns of grey, green and red dots.
What is the History behind color blindness?

  • Most people who are said to be color blind can see some color. Color blindness is a deficiency that prevents a person from seeing all colors. Color blindness is most commonly found in men, approximately 8 percent and 0.4 percent of women are effected.
  • In the 18th century, a chemist by the name of John Dalton diagnosed himself as a color blind person. Mr. Dalton was famously known for developing the atomic theory. Mr. Dalton wrote about his color blindness in himself and his brother. Today, some call color blindness "Daltonism" in honor of John's first description.
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The true name for color blindness is called "Achromatopsia" - complete inability to see color.
  • The gene that causes this condition was discovered on Chronosome 2 in 1997. With this rare condition, both parents must carry the gene but neither are color blind. A baby will have a 25% change in developing achromatopsia and possibliy pass it on to their own children.
  • The first most popular test for color blindness was called "Ishihara." It was developed in 1917. In normal vision patients, they would see a number pattern or some would see nothing at all. In color blind patients would see different numbers within the patterns or see nothing at all.
  • The most accurate instrument used for color blind testing today is called the "Anomaloscope." It was developed in the 20th century and is used by eye specialists all around the world. The Anomaloscope is based on color match. Two different light sources have to match to the same color. One side of the instrument is yellow color tones which you adjust brightness. The other side consists of red and green light mixtures. With a slide bar, a patient would try to match the two colors on each side. This test at the end would prove if a patient was color blind or not.