Study of Frequency Dependence of Reflection Factors for High-temperature Dielectrics

Results are presented of experimental studies of thermal behavior of reflection factors R(λ_л,T) for the high-temperature dielectrics (Аl₂О₃, BNC, SiO₂), conducted under vacuum in the IR-UV spectrum region at the standard laser frequencies (λ_л = 0,241; 0,4416; 0,6328; 0,693; 1,06; 10,6 μm). Experimental results are also given for studies of the group spectrum-average reflection factors (R(Δλ)) under vacuum-UV radiation (hν ~ 10...70 eV) with the pre-threshold density of the radiation power before the beginning of the surface evaporation.