Shilin magnificent gem since ancient times been regarded as treasures, it has been the imperial courtiers as a symbol of wealth and status. Chemical composition of the main gem is α-Al2O3. When the crystals have different metal ion doping, showing gorgeous colors such as ruby (chromium (Ⅲ), red), sapphire (containing Fe (Ⅱ) / (Ⅲ), Ti (Ⅳ), blue), green gem (containing Cr (ⅲ) / ⅴ (ⅲ), green), amethyst (containing Cr (ⅲ) / Ti (ⅳ), purple) and citrine special glossy (containing Fe (ⅲ), yellow). These gems, many may have been carried out by means of high-temperature melting technology industrial manufacturing.In the 1960s, it has become a precious ruby important functional materials, forged a bond with the laser pointer.
Laser is one of the great inventions of the 20th century. 1960 people use ruby as the working substance emits laser oscillation excitation, followed by helium, neon, carbon dioxide and other gases and semiconductors, dyes and other substances as working to achieve a laser oscillation. Laser having a high energy density, coherence is good and excellent color and other characteristics. Laser energy density higher than the surface of the sun more than 10 billion times, after focusing can produce tens of thousands of degrees to a high temperature of several million degrees, have been applied to refractory metals, high temperature ceramics, semiconductors, precious stones, diamonds and other materials, drilling, cutting, welding and heat treatment. Very narrow linewidth laser, ruby laser wavelength is emitted 694.3nm, the linewidth of 0.01nm, and helium-neon gas laser line width of only one part per hundred million
nm. Makes such good monochromatic laser become a standard ruler for precision measurement of length. Good coherence laser interferometry has been applied, holography, optical information processing and other high-tech in.
Substances known burning laser pointer for generating a laser working substance, which is the heart of the laser. Laser material may be a gas, liquid or solid. Although developed hundreds of solid-state laser material, but the actual use of the best mainly ruby, neodymium-doped yttrium aluminum garnet, four kinds of neodymium-doped yttrium aluminum and neodymium glass.
Ruby is the earliest human synthetic crystal gemstone material. 1891 French hydroxide flame doped with a small amount of chromium Al2O3 powder prepared by heating and melting ruby. It was the first oscillation of the laser material, the excitation light using a xenon lamp pump, pulse mode. Ruby laser pulse generated by the light pulse excitation 300 ~ 500μs, the peak power of up to 109 ~ 10W.