The purity of the component gas in the laser mixture directly affects the performance of the laser, especially the presence of impurities such as oxygen, water and hydrocarbons in the gas will lead to the loss of laser output power on the mirror (surface) and electrode, and will also cause the instability of laser emission.

The purity of the laser mixture component has special requirements, and the cylinder packaging the mixture must also be dried before filling to prevent contamination of the mixture. If the helium (He) neon (Ne) laser as the first generation of gas laser, carbon dioxide laser is the second generation of gas laser, in the semiconductor manufacturing field will be a large number of KrF laser, can be called the third generation of laser.

Mixture of laser light is used to produce the laser laser generator gas, the gas quality requirement is high, the laser mixture preparation high accuracy, high purity carbon dioxide purity of 99.999%, the purity of high purity nitrogen 99.999%, the purity of high purity helium requires 99.999%, carbon dioxide is the laser, helium gas is cooled laser, nitrogen gas is balance, the moisture in the gas, oxygen, organic gas impurities of lens injury especially in laser machine, can quickly reduce the service life of the lens. So the laser machine has a very high requirement for the mass of these gases.

The auxiliary gas of laser cutting is mainly dry air, high-purity nitrogen or industrial oxygen. When cutting stainless steel plate or aluminum plate, high-purity nitrogen is generally used as the auxiliary gas, and the general pressure requirement is relatively high.