The selection of lenses is also a matter of attention for lenses from kids' eyeglasses online. Firstly, you need to understand the refractive index, Abbe number, brand characteristics, and the differences between each category of the brand, which can have an impact on the use of lenses.
Everyone has different needs, data, usage habits, and so on for the lens of cheap eyeglasses near me. The lenses that suit everyone naturally differ. If someone says that a certain lens is definitely good, then the intention is somewhat worth pondering.
The first thing we want to talk about is the refractive index, which you can better understand by treating it as' density '. The data related to it includes two dimensions: thickness and hardness.
If you have a high degree and do not want the thickness of the lens, choose a higher refractive index. Hardness refers to the degree of wear resistance. If your lenses are often scratched, you can also increase the refractive index to reduce lens wear.
Of course, there is another option, customized slim lenses. It is a 1.74 lens customized using progressive technology, which can be very thin in thickness.
Another parameter is the Abbe number, which is after selecting the refractive index (children's eyeglasses need to first select the Abbe number before selecting the refractive index, with different priorities). In fact, understanding it as a resolution would be better. The larger the Abbe number, the less likely the lens is to distort. So after selecting the refractive index based on the degree, it would be better to choose a higher Abbe number as much as possible.
Finally, the category of lenses and the selection of film layers are different for each brand.