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Color blindness is a condition that prevents you from seeing colors accurately. There may be certain colors that you can’t tell apart. Both eyes are typically affected, and it’s a lifelong condition that cannot be permanently reversed.

The inability to see colors normally occurs because cones in the retina which detect color aren’t present, don’t function properly or misinterpret one color as another. Color blindness can occur if there is an issue with one or more cones.

  • If three cones are missing or not working properly, the affected person will have severe color blindness.

  • If all three cones are present but one doesn’t function properly, the affected person will have mild color blindness.

With mild color blindness, you may be able to see colors normally in bright lighting but have difficulty telling them apart in low lighting. Severe color blindness usually means you can’t tell certain colors apart no matter how good the lighting is.

The most severe form of color blindness causes you to see everything in shades of gray. This is extremely rare.



There are two main types of color blindness: red-green and blue-yellow.

Red-green color blindness

Red-green color blindness is the most common type. Either the red cone or the green cone is affected, so the ability to perceive either red or green is affected. If the red cone is the problem, you may see red, orange, or yellow shades as greener than they actually are and colors in general as dull. Or, you may see red shades as black and some yellow, orange, and green shades as yellower than they actually are.

If the green cone is the problem, you may see green and yellow shades as redder than they really are and be unable to distinguish purple from blue. Or, you may see green shades as beige and red shades as yellowish-brown.

Blue-yellow color blindness


Blue-yellow color blindness doesn’t occur as often as red-green color blindness. The cones that perceive blue are affected, so blue shades appear greener than they really are, and you may have difficulty distinguishing yellow and red from pink. In other cases, yellow shades may look purple or gray.



In order for color blindness correction glasses to be effective, they must address the type of color blindness that you have. Most glasses are designed to correct red-green color blindness. There are a wide variety of options to choose from. If you suffer from blue-yellow color blindness, however, there aren’t as many options on the market.

Before you buy a pair of color blindness correction glasses, be sure read the FAQ's and complete the online testing. You want to make sure the glasses will correct the type of color blindness you have.


Trichromats are the people who can see normal color vision, this is because their vision uses all three types of light cones correctly.



Those who have deuteranomaly will typically experience greens, yellows, browns and reds to appear redder or similar. As a result their green cone sensitivity is moved towards the red sensitive cones. Colors such as purple will be difficult to distinguish from blue.


This is where the green sensitive cones are missing and are not working at all, typically resulting in only distinguishing two to three different hues, consequently allowing them to only see reds as brownish-yellow and greens as beige.



This is where if your L-cones are not missing but are defective, which means you have a weakened ability to differentiate between some hues of reds and greens; further making it difficult for you to see red, orange and yellow as it may appear greener or the colors are not as vibrant as expected.


This is present when your L-cone is missing resulting in you only having a short - medium wavelength which affects your intensities to red light, leaving you with two working cones, enabling your reds to appear as black and certain shades of orange, yellow and green to all appear as yellow.



This is where the S-cones are functionally limited which the person with this deficiency will struggle with blues as it will appear greener and it can be difficult to tell yellow and red from pink.


Those with tritanopia have only medium and long wavelength as their S-cones are missing. This makes the blue appear as green and yellow appear as violet or light grey.

Monochromatic people will see no color at all, this means everything they see will be in shades of grey. It is a rare subtype of color blind deficiency with different types within monochromacy such as Rod monochromacy and cone monochromacy. Occurs from both when none of the cone cells have functional photopigments or from a failure of two of the three cone cell photopigments to work.

Here at Pilestone, we're able to color correct your vision with our high-tech glasses. Shop our collection and find the best glasses that'll suit you. If you want to live a colorful life, then shop at Pilestone, we'll provide you glasses that are worth seeing through.