| 摘要 |
PURPOSE:To obtain a total reflection mirror for CO2 laser having high reflectance and high damage threshold by laser light by polishing a substrate of a hard metallic material such as Mo or W with diamond abrasive grains then with working liquid suspended with diamond abrasive grains. CONSTITUTION:A substrate of a hard metallic material such as molybdenum or tungsten is first mechanically polished with diamond abrasive grains in order to obtain the shape of an accurate reflection surface, whereby said shape is realized. The work hardened surface layer is still large in this state; therefore, the substrate is subjected to the operation of removing only the work hardened surface layer produced in the previous stage without collapsing the shape in the 2nd stage. For this purpose, the substrate is polished with liquid having a chemical etching effect, for example, the working liquid prepd. by suspending diamond abrasive grains in liquid having a very weak chemical etching effect, and the surface polished in such a way is used as a reflection mirror, whereby the total reflection mirror is obtained. |
