Color blindness and color weakness are both manifestations of abnormal color vision, usually associated with hereditary diseases, and rarely caused by acquired causes. Although color blindness and color weakness are both manifestations of abnormal color vision, there are differences: a. Color blindness is the inability to distinguish colors, i.e., the loss of the ability to distinguish colors. According to the doctrine of three primary colors, those who cannot distinguish red are red-blind, those who cannot distinguish green are green-blind, those who cannot distinguish blue are blue-blind, and those who cannot recognize all three colors are totally color blind. Second, color weakness means the ability to distinguish colors is weakened. That is to say, a person with color weakness can distinguish all colors, but his ability to do so is slow, or he can only recognize them after repeated consideration. Third, color blindness is the inability to distinguish some colors at all; while color weakness can distinguish colors, but the ability to do so is poorer than normal. Although there is a difference between color blindness and color weakness, there is also a certain relationship between them. Like color weakness there is a difference between light and heavy, serious color weakness patients, is equivalent to patients with mild color blindness, its ability to distinguish colors will be very poor; color weakness and color blindness, like male patients more than female. There is no effective treatment for color blindness and color weakness caused by hereditary diseases.