| 摘要 |
PURPOSE:To decrease noise and to prevent distortion in images by allowing specified amts. of radio isotopes to be present in glass. CONSTITUTION:The base compsn. of glass is obtd. by compounding 50-75wt.% SiO2, 0.2-5.0wt.% Al2O3, 5-20wt.% B2O3, 0-1wt.% Li2O, 0.5-9.5wt.% Na2O, 0.2-6wt.% K2O, 5-12wt.% Li2O+Na2O+K2O, 0-3wt.%, 0-5wt.% CaO, 0-6wt.% BaO, 0-5wt.% ZnO, 0-12wt.% MgO+CaO+BaO+ZnO, 0-1wt.% As2O3, 0-1wt.% Sb2O3, 0-0.2wt.% Cl<->, 0-0.5wt.% F<->, and 0.02-1.5wt.% As2O3+Sb2O3+Cl<->+F<->. This compsn. is moten to obtain a window glass for a solid-state image pickup element package containing <=100ppb total amt. of radio isotopes, <=0.05c/m<2>.h alpha-ray emission and 48-75X10<-7>k<-1> coefft. of thermal expansion. |
