Effects of Space Environment Factors on Optical Materials for Space Application

The effects of proton and electron radiations as well as thermal cycling on properties of optical materials for space application were studied using a complex simulator for space environment. The energy of protons and electrons ranged from 60 to 180 keV that is within the energy range of the Earth radiation belt. The temperature interval of thermal cycling, Δ, was kept between 80 and 400K. The obtained results showed that if the reflectors were not grounded directly, charging-and-discharging could cause severe damage of the reflector surface. Bulging or exfoliating of the surface films would be more severe due to synergistic effect of proton radiation and thermal cycling on the reflectors. For JGS3 quartz glass, the proton and electron radiations result mainly in the ultraviolet absorption at 210–240 nm, while an absorption in visible range also occurs in the case of high radiation fluence.