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For Your Eyes Only Optometry is located in the heart of the Castro, at 552 Castro Street, between 18th and 19th streets. Look for our brown awning in the middle of the block, which leads you upstairs to the 2nd floor.

552 Castro Street, San Francisco, CA 94114
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Home » What's New » How We Perceive Color: What is Color Blindness?

How We Perceive Color: What is Color Blindness?

Color blindness is a disorder affecting one's ability to distinguish colors with typical light or to perceive colors as they are typically viewed. Typically, the disorder is inherited, but it can also be a result of accidents or a number of eye diseases.

Color perception is dependent upon cones found in the eye. Humans are usually born with three varieties of pigmented cones, each perceiving different wavelengths of color. This is comparable to the wavelengths of sound. With colors, the size of the wave is directly associated with the resulting color. Long waves produce reds, moderately-sized waves generate green tones and short waves project blues. Which pigmented cone is affected determines the spectrum and seriousness of the color blindness.

Red-green color vision deficiencies are more frequent in men than in women because the genetic code is linked to gender.

Color vision problems are not a devastating disability, but it can damage educational development and limit options for professions. The inability to see colors as peers do can permanently harm a student's confidence. For anyone in the workplace, color blindness could present a drawback when running against colleagues trying to advance in the same industry.

There are a few examinations for color blindness. The most widely used is the Ishihara color exam, named after its designer. For this test a patient views a plate with a group of dots in a circle in different sizes and colors. Inside the circle one with proper color vision can see a digit in a particular tint. The individual's ability to make out the digit within the dots of contrasting colors determines the level of red-green color vision.

While genetic color blindness can't be treated, there are a few steps that can help to make up for it. For some, using tinted lenses or glasses which minimize glare can help to perceive the differences between colors. More and more, new computer applications are being developed for regular PCs and even for smaller devices that can assist people to enhance color distinction depending upon their specific diagnosis. There is also exciting research underway in gene therapy to improve the ability to distinguish colors.

The extent to which color vision problems limit a person is dependent upon the type and severity of the condition. Some patients can accommodate to their deficiency by learning alternate clues for determining a color scheme. For instance, they can learn the shape of traffic signs instead of recognizing red or compare objects with color paradigms like the blue sky or green trees.

If you notice signs that you or a loved one could have a color vision deficiency it's recommended to schedule an appointment with an optometrist. The earlier the condition is diagnosed, the easier it will be to live with. Contact our San Francisco, CA optometry practice for information about scheduling an exam.