What are color blindness and color weakness?

According to the tricolor theory, different proportions of red, green and blue can be adjusted to any color. Then if the brain is compared to a palette, the three photosensitive pigments are red, green and blue brushes. If there is little or no pigment on the red brush, there will inevitably be some colors that cannot be adjusted, or the adjusted colors are incorrect.

Similarly, on the palette of the brain, the proportion of red sensitive pigment is small, red is weak, green is weak, blue is weak; Accordingly, people who lack red-sensitive pigments are red-blind, those who lack green-sensitive pigments are green-blind, those who lack blue-sensitive pigments are blue-blind, and those who lack two kinds of light-sensitive pigments are called monochromatism, also known as color blindness. For example, a patient with pinkeye may regard pink as brownish gray.