Red-green color blindness
It occurs when red or green cone cells do not function properly, or are completely absent. Have some kind:
Mild green blindness: This is the most common form of color blind test and affects 5% of men, but is rare in women. It occurs when green cone cells do not function as they should. Yellow and green look redder, and it can be difficult to distinguish blue from purple.
Mild red color blindness: It happens when your red cone cells don't work like they should. Orange, red, and yellow look greener, and the colors are less bright. It is usually mild and does not cause problems in daily life. This form of color blindness is very rare in women and affects about 1% of men.
Red color blindness: You don't have working red cone cells. Simple red looks dark gray. Some shades of orange, yellow and green look yellow. It is very rare in women and affects about 1% of men.
Green blindness: occurs when you don't have working green cone cells. Red can be yellow-brown and green can be beige (pale yellow-gray). It affects 1% of men and is rare in women
Blue-yellow color blindness
This type of color blindness affects men and women equally. This condition occurs in less than 1 in 10,000 people worldwide.
It happens when your blue cone cells are missing or don't work correctly. This is the second most common type, and it affects men and women equally.
Mild blue-yellow color blindness: occurs when your blue cone cells function in a limited way. Blue looks greener and it's harder to see pink from yellow and red. It is extremely rare.
Blue-yellow color blindness: it occurs when you don't have blue cone cells. Blue looks green, and yellow looks light gray or purple. It is extremely rare
Completely color blind
You don't see any color at all and your vision may not be clear.
There are two types:
Complete cone color blindness: It occurs when 2 of your 3 cone cells: red, green or blue, don't work. When only one type of cone is active, it is difficult to distinguish one color from another. And if one of your defective cones is blue, your vision may not be sharp. You may be nearsighted and may experience uncontrolled eye movements. This is a condition called nystagmus.
Complete rod color blindness: It is the most severe form of color blindness. None of your cone cells have active light-sensitive pigments. As a result, the world appears to you in black, white, and gray. Bright light can hurt your eyes. You may experience uncontrolled eye movements (nystagmus).