| 摘要 |
A glass which transmits far into the IR and which has a difference of at least 150 [deg]C. between crystallisation and transition temps. has the compsn. (mole%) 55-95 GeS2, 2-40 As2S3 and 0.01-20 R2S3, where R comprises: Ga and/or In network forming cation, 0-10% MSx(M is one or more of Al, Sb, Ba, Cd, Ca, Pb, Li, Hg, K, Ag, Na, Sr, Th, Sn, Y and a lanthanide metal), 0-20% of a chloride and/or fluoride, and 0-5 total selenide - S and/or Se can vary between 85 and 125% of stoichiometric. Also claimed is a glass as above wherein the difference between crystallisation and transition temps. is at least 200 deg. C and the compsn. is 60-95 GeS2, 5-30 As2S3 and 0.1-15 R2S3 where R is a described above except chloride and/or fluoride is 0-10%, total selenide is 0-3% and S and/or Se can vary from 90 to 120% of stoichiometric. |
