In the discussion of “What is the optical refractive index of an eye lens?” When it comes to this problem, we first need to understand the physical concept of optical refractive index, ...
When discussing the topic of how to buy glasses frames for children, we first need to make it clear that the choice of glasses frames is not only a consideration of beauty and fashion, but also rel...
Wenzhou is one of the most prominent cities. Wenzhou is regarded as the “Optical Capital of China” and has a large number of wholesale markets that can meet the global demand for glasse...
1. Nose pads
Different from adults, children’s heads, especially the angle of the nose peak and the curvature of the bridge of the nose, have more obvious differences. Most children have...
Relevant standard
Ultraviolet protection factor (UPF)
Definition: UPF is a measure of the ability of a fabric or material to block ultraviolet light, and in the case of sunglasses, it reflects the ...
What is cellulose acetate?
Cellulose acetate refers to a thermoplastic resin obtained by esterification with acetic acid as a solvent and acetic anhydride as an acetylating agent under the action o...