Temperature field design of optical thin film coatings

Thermodynamics of thin film coatings under laser irradiation is a fundamental process for laser-induced damage studies as well as many other relevant applications, including optical data storage and laser processing / laser conditioning. Temperature distribution within a thin film coating depends on not only the coating materials but also its design. When the design of the thin film coating changes, a variation of the temperature field will emerge. Based on this understanding the idea of optimizing the temperature field is introduced in the design of optical thin films for high power laser applications. By analyzing photothermal process, the temperature distribution within a thin film multilayer, together with required optical performance, is used as the major criterion for the design. The results of optimized design for a high reflective coating and a photothermal functional coating are shown as examples to demonstrate the temperature field design idea.