The function of the optic cone cells is to perceive strong light and the color of the light, and the function of the optic rod cells is to perceive weak light and dark vision. Both cone cells and rod cells are light-sensitive cells of the retina, and they are located in the outer layer of the retina. Cone cells are located in the macula, the closer to the central pit, the denser and more, and their main function is bright vision and color vision, i.e., to see things during the day and distinguish colors. Once the cone cells become diseased, there will be a loss of vision and color vision. Rod cells are more and more numerous in the periphery of the retina and less and less in the macula, and their main function is dark adaptation, i.e., the ability to adapt at night without turning on the lights. Night blindness occurs when the optic rod cells become diseased. When visual abnormalities occur, it is recommended to consult an ophthalmologist promptly to avoid delay.