1.56 anti-blue light lens refers to: the refractive index is 1.56, and the lens with anti-blue light function. When the lens power and material are the same, the higher the refractive index, the thinner the lens will be. Therefore, people with high myopia will choose those lenses with high refractive index. Within 500 degrees, you can choose 1.56 refractive index lens. If the degree is above 500 degrees, because of the thickness of the lens, you must choose a lens with a higher refractive index.