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...
Product characteristic class
The principle and application of polarized sunglasses: mainly involves how the polarized lens filters the light in a specific direction, reduces glare, and the practica...
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...
The material of children’s glasses has an impact on the replacement frequency. Different frame and lens materials vary in terms of durability, adaptability, etc., as follows:
Frame material
P...
Effect of refractive index on visual acuity in the aged
Lens thickness
For the elderly with high myopia or farsightedness, it is more appropriate to choose a lens with a high refractive index. The ...
Uv protection
View the logo: It is preferred to choose sunglasses with a clear UV protection logo, such as “UV400″, which means that the sunglasses can block more than 99% of the ultrav...