When the clarity of the lens is determined to be correct, there are two main considerations. One is whether the kids eyeglasses online lens is clear when first worn, that is, whether the material of the lens is good or not. The second issue is that after wearing it for a long time, it is unclear how the production process is and whether it is easy to scratch.

First, let's talk about the first point: unclear material when wearing it. Many green control lenses on the market use 1.60 PC material, which has a relatively low Abbe number of only 31. As we all know, the lower the Abbe number, the more obvious the dispersion, and the more blurry the imaging. In summary, the clarity of this PC material is not good enough.

So if possible, it is recommended to switch to lenses made of 1.60 resin material, with an Abbe number of 40, which will improve the clarity of the viewing experience.

Speaking of refractive index, I would like to add another sentence. If a child has high myopia (combined luminosity exceeding 500 degrees), I suggest choosing lenses with a refractive index of 1.67 or 1.71, because the higher the refractive index, the thinner the kids eyeglasses online lens.

It doesn't matter if the refractive index is low or medium, but if you don't choose high refractive index lenses for height, the entire pair of glasses will be relatively heavy, after all, overweight kids eyeglasses online will affect the development of children's nose bridge.

You can choose different refractive indices, but it should be noted that the higher the refractive index, the more expensive the price. If the degree is relatively low, from the perspective of cost-effectiveness, a refractive index of 1.56 is also a good choice.