A Brief Review of Methods for Increasing the Service Life of Laser Metal Optics

摘要

The experience gained during the operation of laser metal optics required a new approach to the technology of preparing mirrors. The operational properties of mirrors directly depend on the energy state of the surface described by such parameters as reflection coefficient, roughness, optical purity, adhesion durability, threshold optical breakdown, etc. Cleaning and/or modification of the surface affect these properties actively, since a surface layer with charged inside technological impurities is formed during the manufacture of mirrors. This layer differs in structure and properties from the bulk of the material significantly. When choosing a detergent medium, it is necessary to take into account the increased chemical activity of the surface in view of the properties of the metal, as well as the necessity of preserving the optical parameters of the surface after cleaning and/or surface modification. Oxygen-free metal surfaces are more difficult to clean in the case of complex contamination; however, in the overwhelming majority of cases, when cleaning metal optics, we have to deal with an oxide-covered surface.