The replacement frequency of children’s glasses is influenced by multiple factors. Generally, it is recommended to replace them every half a year to a year. The following is a specific analys...
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 ...
Metal, TR90 and other materials of the sunglasses frame is more durable, the following is the specific analysis:
Metal material
Strong and durable: The metal has high strength and hardness and is n...
TR-90 (plastic titanium) is a kind of polymer material with memory. It is the most popular ultra-light spectacle frame material in the world. It has the characteristics of super toughness, impact r...
China
Relevant standards: mainly based on GB 10810.3-2006 “Glasses lenses and related glasses products Part 3: Transmission specifications and measurement methods” and GB/T 14214-2003 &...
Material aspect
Look at the material composition: high-quality metal spectacle frames often use titanium alloy, pure titanium, etc., with light weight, high strength, corrosion resistance, anti-all...
