Methods To Assist With Color Blindness

I recently read a comment from a DCT reader who indicated that he had difficulty identifying a link on our DCT pages because he is color blind. I thought, there must be a method of changing colors or themes on a computer to improve vision for color blind people. I did a little research and came up with some methods that color blind individuals can try to improve their computer experience. However, not being color blind myself, I have no way of verifying how well these methods may work.

What Is Color Blindness?

Color blindness, also known as color vision deficiency (CVD), affects 300 million people worldwide. Of these, 95% are men. We are all born color blind, but, our color vision is usually fully developed by six months of age.

Normal color vision uses three types of properly functioning cone cells. Color blindness is not actually a blindness, it is a form of deficiency in the ability to see colors or differences in colors. There are three main types of color blindness ranging from partial to complete lack of color discrimination.

Red-Green Color Blindness

The most common type of color blindness (98%) is red-green color blindness. These individuals have difficulty distinguishing between certain colors such as yellow and orange, green and brown, pink and gray, or blue and purple. Red-green color blindness is usually inherited via X-linked recessive genes:

Deuteranomaly is a reduced sensitivity to green light. It is the most common type of red-green color blindness. It makes green look redder
Protanomaly is a reduced sensitivity to red light. It makes red look greener and less bright
Protanopia is the inability to perceive ANY red light
Deuteranopia is the inability to perceive ANY green light

Blue-Yellow Color Blindness

Blue-yellow color blindness is associated with the inability to see shades of blue. These individuals confuse blue with green colors and yellow with violet. These individuals have defects that affect the short-wavelength cone (S-cone) and are usually caused by age-related eye conditions such as glaucoma, or exposure to certain chemicals or medical treatments:

Tritanomaly is a reduced sensitivity to blue light
Tritanopia is the inability to perceive ANY blue light

Complete Color Blindness

In very rare cases, a person can be completely color blind, meaning they cannot see colors at all, only the intensity of light. This is called monochromacy.

Color Blindness Test

Are you color blind? There are many tests available online to check for color vision deficiency. Most are based on a method developed by Professor Shinobu Ishihara at the University of Tokyo who first published it in 1917. The tests use a circle of colored dots of varying colors and sizes where a number is clearly visible to those with normal color vision, and invisible, or difficult to see, to those with color blindness. I took the Enchroma online test, which claims to be the #1 test on the web, and it determined that I have normal color vision and can see up to one million distinct shades of color.

Windows Color Filters

Microsoft added color filters to Microsoft Windows in version 10. They are also included in version 11. Color filters change the color palette on the screen and can help you distinguish between objects that differ only by color. Microsoft added color filters for deuteranopia and protanopia (the two types of red-green color blindness) as well as tritanopia (blue-yellow color blindness). Microsoft also added color filters for grayscale, inverted grayscale, and inverted color scale. If you are color blind or have another type of vision impairment, one of these color filters may help.