First of all, do not ignore the important aspect of optometry. It was to make life easier, it is unscientific to buy ready-made glasses, or use others' glasses. Whether or not the first time you buy prescription glasses, you must see the eye doctor first, so that you can distinguish between myopia and pseudo-myopia, especially primary school students, pseudo myopia can restore vision if protective measures are used in time. Eye refractive errors are divided into myopia, hyperopia, and astigmatism, each is divided into different types. Therefore, inappropriate glasses are harmful to your eyes. Do not buy made-ready glasses, they are harmful to your eyes. You have to choose your eyeglass frame, fill in your glasses prescription, and select a lens, usually, it takes 7 - 14 days for the new glasses. Qualified and comfortable glasses depend on two factors: First, the accuracy of optometry, and second, the glasses prescription. If you want to buy glasses for your kids, pay attention to the glasses frames and the lenses. Generally, the lenses are divided into resin lenses, glasses lenses, and crystal lenses. Children are very active, so it is recommended to choose a resin lens, because of its lightweight. Select glasses frames according to Pupil, you can not select big frames if your pupil is small, otherwise giving the appearance an uncomfortable feeling. it is best not to select the frame stuck to his cheek, otherwise, it will affect the normal visual objects.