Resonator gases are used in gas lasers to generate laser light. The gas mixture for a CO2 laser contains helium, nitrogen and carbon dioxide. Other additives are used for certain laser types e.g. oxygen, hydrogen, xenon and carbon monoxide. Gas mixtures for excimer lasers often consist of halogens, noble gases (krypton, xenon or argon) and buffer gases (helium or neon). A modern carbon dioxide laser requires laser gases of high purity. Excessive amounts of impurities may affect the output of the laser. The lifetime of the optical components may also be affected. In this context, water vapour and hydrocarbons are the most critical impurities.Laser gases for carbon dioxide lasers are supplied in separate gas cylinders, and are mixed in the laser via a mixer, or as pre-mixed gases. All gases are included in the LASERLINE program. Premixed resonator gases for different laser types are included in the Lasermix program.
Beam protection
The presence of impurities such as particles, argon, oxygen, water vapour and hydrocarbons in the laser beam path has a negative effect on the actual laser beam. The beam’s quality is affected, as well as the lifetime of the optical components. To avoid this, a beam path protection gas is used for certain high power CO2 laser applications. Laser Cutting Nitrogen 4.6 or Laser Nitrogen 5.0 is normally used for beam path protection. Typical flow rates are 1-3 m³/hour.
