The characterization of continuous-wave (cw) laser-induced damage threshold (LIDT) requires a suitable measurement routine to obtain reliable results. In this study, we show that the existing measurement protocols are of limited use for cw-LIDT measurements. On the basis of testing several mirrors with varied distance and number of spots on the samples an adapted protocol for the damage behavior under cw laser irradiation is proposed. We observed a significant effect governed by debris and induced stress of induced damages on the damage behavior of subsequent irradiation spots. Finally, we performed a parametric study on the optical properties of mirror designs consisting of a metal and a dielectric multilayer film and demonstrated the LIDT dependence on the thermal conductivity of the substrate and the absorption of the components.

Random effects in the reproducibility of refractive index and absorption edge position of Ta2O5 layers prepared by plasma-ion assisted electron beam evaporation, ion beam sputtering and magnetron sputtering are investigated and quantified.

The environmental effect on the aging behavior of NaCl and KCl windows was studied. Laser windows were aged at different relative humidities in a controlled climate-chamber. Degradation is monitored with a microscope inspection system equipped with a computer controlled image processing board. The temporal development of surface defect density under different atmospheric conditions was investigated with respect to optical absorption and damage thresholds of the windows at 10.6 micrometers . Laser windows coated with single layers of NaF deposited by an adapted IAD-technique were analyzed. The performance of the coated and uncoated laser windows is discussed under consideration of typical applications. In comparison to the bare samples, the coated windows show an improved resistivity against environmental influences. Accelerated testing theory is employed to model the aging behavior of the samples. An approach to deduce a qualified acceleration factor is made in order to extrapolate the lifetime of alkali halide laser window under normal conditions.