| abstract |
The invention relates to vitreous compositions, in particular of the vitroceramic type, transparent to infrared, production and uses thereof. Said compositions comprise in mol. %: Ge 5-40, Ga<1, S+Se 40-85, Sb+As 4-40, MX 2-25, Ln 0-6, adjuncts 0-30, where M=at least one alkaline metal, selected from Rb, Cs, Na, K and Zn, X=at least one atom of chlorine, bromine or iodine, Ln=at least one rare earth and adjunct=at least one additive comprising at least one metal and/or at least one metal salt with the sum of all molar percentages of the components present in said composition being 100. |