Generally, sapphire glass is used for watch mirrors in general famous watches, because sapphire crystals have high hardness and are not easy to scratch. The glass commonly used in clock mirrors can be roughly divided into three types: molecular compound plastic glass, ordinary glass and sapphire glass.
Molecular compound plastic glass refers to acrylic. Most watches in the past used this material, and many watches are still in use today.
The disadvantage is that it is easy to scratch, and the light transmittance is slightly poor, but because of its elasticity, it is not easy to crack, so it is also called tempered glass.
Although molecular compound plastic glass is easy to scratch, but when it shows scratches, it can be directly polished on the glass to make it smooth. There is no need to change the lens, because the scratches are too deep and the price is cheap.
Sapphire is to remove impurities in the glass to make it into a finished product with better transparency. Most watches use this material as they think it is appropriate. Its unique style is that it is wear-resistant and less scratched than molecular compound plastic glass, but because its hardness is higher than that of molecular compound plastic glass, it is relatively easy to break.
