The Thermal Damage Process of the Contaminated Optical Element Used in High Energy Laser System

摘要

In high energy continuous wave laser system, the optical elements should keep absolutely clean all the time. Even if the optical element is slightly contaminated, it may be seriously damaged. The damage process of the contaminated optical element is studied by a self-build optical element testing platform. Under the irradiation of the high energy cw laser, the contaminated element is damaged due to thermal effect. The damage process can be divided into three gradual stages and a sharp stage. They are laser energy accumulating process, optical film burning and thermal stress accumulating process, element burst process and substrate melting process in sequence. The damage mechanism of the contaminated element is discussed. The investigation of the damage process is of great help for enhancing the anti-damage capability of the optical element and maintaining the security of the high energy laser system.