Abstract: This invention is directed to the production of transparent glasses exhibiting transmission far into the infrared regime of the radiation spectrum. The glasses consist essentially, in mole percent, of 42-55% CdF.sub.2 and/or CdCl.sub.2, 30-40% NaF and/or NaCl, 2-20% total of BaF.sub.2 and/or BaCl.sub.2 +KF and/or KCl, consisting of 0-15% BaF.sub.2 and/or BaCl.sub.2 and 0-7% KF and/or KCl, 1-12% total of at least one stabilizing metal halide selected from the group LiX, BeX.sub.2, MgX.sub.2, MnX.sub.2, PbX.sub.2, TlX, COX.sub.2, and ZnX.sub.2, and 0,005-0.5% REX.sub.3, wherein Re is at least one rare earth metal selected from the lanthanide series of rare earth metals and X is at least one halide selected from the group consisting of fluoride, chloride, and bromide. The preferred glasses contain at least 2% each of BaF.sub.2 and/or BaCl.sub.2 and KF and/or KCl.

Abstract: This invention is directed to the production of transparent glasses exhibiting transmission far into the infrared regime of the radiation spectrum. The glasses consist essentially, in mole percent, of 42-55% CdF.sub.2 and/or CdCl.sub.2, 2-15% BaF.sub.2 and/or BaCl.sub.2, 30-40% NaF and/or NaCl, 2-7% KF and/or KCl, 1-12% total of at least one stabilizing metal halide selected from the group LiX, BeX.sub.2, MgX.sub.2, MnX.sub.2, PbX.sub.2, TlX, CoX.sub.2, and ZnX.sub.2, and 0.005-0.5% ReX.sub.3, wherein Re is at least one rare earth metal selected from the lanthanide series of rare earth metals and X is at least one halide selected from the group consisting of fluoride, chloride, and bromide.