Most of optical coatings have been made by conventional vacuum evaporation. The recent progress of coating technology requests to study the starting materials. No systematic study has been yet done to prove the relationship between optical coatings and their starting materials. This paper introduces the important points of making starting materials and related evaporation processes. It is important to know that the particle size distribution and purity in raw materials. The stable optical coatings require the stable starting materials and relevant evaporation processes. First some evaporation materials, important to produce laser mirrors, for example TiO2, Ta2O5 and SiO2, are described here. Then the relationship between laser damage threshold and starting material of HfO2 is described too.
