People who have color blindness know they do not see the same colors other people do. Most people who do not have it and hear about someone who is color blind wonder what it’s all about. The details of it are interesting.
What Makes People See Different Colors
Eyes see differences in light. It’s a lot like how people hear sounds. Some sounds are quiet while others are loud, and it has to do with the length of the vibration.
Keys on a piano function the same way. The keys on the left side are at a lower frequency but the ones on the right are at a higher one, which is what creates the differences in sound. Light works in the same way.
Rainbows have a series of colors that always display in this order:
- Red
- Orange
- Yellow
- Green
- Blue
- Indigo
- Violet
Each one of these colors corresponds to a different wavelength of light. Red has a longer wavelength, and blue, indigo and violet have shorter ones.
When light enters the eyes, the retina has special nerve cells containing pigments that react to light.
Cones (nerve cells) control your color vision. There are three types of cones that have different kinds of pigment. Some of them react to short wavelengths (blue colors) while others react to longer wavelengths (red and orange colors).
When cones have all the different kinds of pigments to receive short, medium and long wavelengths, all colors can be seen. If there are any problems with the pigment, colors won’t appear as they should. This is when people are diagnosed with a color deficiency or color blindness.
All people don’t experience color blindness the same way. Depending on how many pigments are missing, some people may only have trouble seeing one color.
For those who do not have any pigments in their cones, they don’t see color at all. This condition is called achromatopsia.
Different Types of Color Blindness
There are four types of color deficiencies that people may have:
- Deuteranomaly – This is the most common form and it affects about 5% of men. Sufferers see yellow and green as red, and they have a hard time telling the difference between blue and violet.
- Protanomaly – Orange, red and yellow look green and it’s hard to see bright colors.
- Protanopia – Red looks like black, and orange, yellow and green look yellow.
- Deuteranopia – Red looks brownish-yellow and green may look beige.
Diagnosing Color Blindness
This should be a normal part of a routine eye exam. Many tests exist to measure color vision defects, but the most common is the Ishihara Plate test. This test identifies red/green color blinding but not blue. This can give the eye doctor a sign that further testing is needed.
What Causes Color Blindness
Most people who suffer from color blindness were born with it. The inherited genes are found on the X chromosome, which is why 1 in 12 men and 1 in 200 women suffer from it worldwide.
People who are not born with the color deficiency often suffer physical or chemical eye damage. They may have damaged their optic nerve or even the part of the brain that processes color information. Cataracts can affect how people see color as well.
When to See an Optometrist for Color Blindness
Serious eye and head injuries should be treated at an emergency room. The emergency room may refer someone who has sustained lasting injures to an optometrist. If the injury occurred a long time ago, an optometrist may be the best choice to check if color blindness is an issue.
Can Laser Eye Surgery Help Color Blindness?
One of the most common questions people with color blindness ask is if laser eye surgery can help. Unfortunately, it cannot correct color blindness. It’s possible technological advancements may be able to treat the condition with surgery in the future, but until then color correcting glasses and lenses is all that is available for treatment.
