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...
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...
Metal material
peculiarity
Titanium alloy: with light weight, high strength, corrosion resistance, no allergic reaction and other advantages, is a common material for high-end spectacle frames. It ...
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...
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 ...
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 ...