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...
Choosing the optical lens material suitable for the elderly requires comprehensive consideration of the elderly’s eye needs, physical conditions and living habits. The following is a specific...
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 ...
When discussing the question of whether sunglasses are better polarized or unpolarized, we first need to clarify the core differences between the two and their applicability in different scenarios....
The color depth of sunglasses and eye protection ability is not a simple positive correlation, the following is the specific analysis:
Sun glasses color action principle
The color of sunglasses is ...
Choose a frame suitable for children’s face, mainly considering the characteristics of different face shapes and children’s facial development, the following are some basic selection me...