You are here

Sapphire crystal with anti-reflective coating

The type of crystal used on a watch is a very important factor to consider when making a watch purchase. The better or harder the crystal, the more likely you are to keep the crystal free of scratches. There are several different qualities of crystals available on watches today,. In descending order they are:
 
Sapphire Crystal
Sapphflex Crystal
Hardened Mineral Crystal
Acrylic (Plastic)
 
Sapphire Crystal
Sapphire crystals are generally reserved for the finest watches due to their manufacturing expense. A sapphire crystal is literally a lab grown sapphire that has been shaped and polished to fit the face of the watch. Because of the incredible hardness of sapphire, these types of crystals are nearly impossible to scratch.
 
Sapphflex or Hybrid Crystal
The Sapphflex crystal was introduced by Seiko Watch Corporation in the early 90′s. This crystal uses a thin sheet of sapphire crystal which has been bonded to the top of a mineral crystal. Due to the hardness of the thin sapphire crystal, these types of crystals rarely scratch.
 
Hardened Mineral Crystal
The mineral crystal is the most common type of watch crystal used in mid-range watches. This crystal is hard, but not as hard as a sapphire crystal, hence it is more likely to be scratched over years of wear.
 
Acrylic (Plastic)
This clear material has been used for many years as a way to protect and enclose the face of a watch. It is very soft and very susceptible to scratching. An acrylic watch face is the only face that can be buffed occasionally to remove scratches. This is the cheapest type of watch face, but has been used on all ranges of watches over the years.
 
Anti Reflective Coating (AR)
An antireflective or anti-reflection (AR) coating is a type of optical coating applied to the surface of lenses and other optical devices to reduce reflection. This improves the efficiency of the system since less light is lost. AR can be aplied to the external surface of the crystal or it can be applied to both external and internal surfaces.