Introduction of sapphire glass watch glass
Introduction of sapphire glass
Sapphire glass (SAPPHIRE CRYSTAL) generally refers to synthetic sapphire, which is very different from the jewelry that people usually understand - natural sapphire. It is generally used in the manufacture of watch mirrors.
It is a wear-resistant material with tungsten titanium alloy and high-tech ceramics. Although these materials are resistant to wear, they cannot withstand strong impacts. At the same time, some substances with the same or higher hardness (such as grinding stones, sandpaper, nail files, granite surfaces, concrete walls and floors, etc.) may Scratch the surface of these materials.
Sapphire is a general term for corundum gemstones of other colors except red ruby. The main component is aluminum oxide (Al2O3). Sapphire glass refers to synthetic sapphire, gem-quality sapphire can be easily and cheaply produced in the laboratory, and its chemical composition and physical properties are the same as natural sapphire.
Chinese name (蓝宝石水晶玻璃）
foreign name SAPPHIRE CRYSTAL
Features and uses
Sapphire glass. Similar to corundum, the hardness is 9, and various colors can be generated by adding various chemical elements. The commonly used one is colorless. Its advantages are higher than ordinary glass, and its price is relatively high. It is mainly used to make high-end watch mirrors.
Sapphire glass/ruby glass has good thermal properties, excellent electrical properties and dielectric properties, and is resistant to chemical corrosion. It has high temperature resistance, good thermal conductivity, high hardness, infrared transparency, and good chemical stability. Therefore, it is often used to replace other optical materials to make optical components and infrared-transmitting optical windows, and is widely used in infrared and far-infrared military equipment, such as night vision infrared and far infrared sights, night vision cameras and other instruments In the instruments and instruments of satellite and space technology, as well as windows for high-power lasers, various optical prisms, optical windows, UV and IR windows and lenses, observation ports for low-temperature experiments, and high-precision instruments for navigation, aerospace, etc. be fully applied.
Identification
(1) Laboratory method: Detecting whether it is sapphire glass is very similar to the identification of jewelry, and the equipment used is the same. The most commonly used instrument for jewelry identification is the refractometer, which can measure the refractive index of the object to be tested. Although the sapphire watch glass is artificial, its refractive index is the same as the natural one, which is 1.76~1.77. Because sapphire glass is a crystal, it has a birefringence like crystal, which is 0.008. , rotate the polarizer on the observation eyepiece, you can see it clearly. The flat watch glass is best to observe, the spherical surface is not very good-looking, and it is necessary to apply refraction oil during the test. Mineral glass has a refractive index of about 1.52, which makes it easy to distinguish it from sapphire, and it also has no refraction. Another method is to use a polarizer. Any crystal can be checked with a polarizer, such as crystal. Sapphire is also a crystal. When the polarizer is rotated, the light and dark will change alternately, with a cycle every 90 degrees. However, when checking the watch glass with a polarizer, the entire movement needs to be taken out to expose the watch glass. But some non-sapphire watch glass may also have a polarizing effect, because it is also made into a crystal, such as the word Crystal.
(2) Look at the logo of the watch and the hardness of the glass: if it is a regular brand watch, the sapphire glass will generally be printed on the back cover of the watch, expressed in English SAPPHIRE or Sapphire Crystal, even if it is a fake or counterfeit watch, use sapphire watch glass are also common. To test the hardness of the watch glass, a sharp metal object similar to a needle can be used to scratch the most inappropriate part of the edge of the watch glass. grass.
Sapphire display.
