Further Measurements on the Optical Properties of Lead Sulphide, Selenide and Telluride

Earlier work on the optical properties of PbS, PbSe and PbTe is briefly reviewed. Measurements, using reflection techniques, of the optical constants of all three compounds are reported for wavelengths up to 6 μ. The variation of the optical constants with temperature for some specimens of PbS is described and discussed, and the effect on the constants of baking the specimens in O 2 at a few millimetres pressure is described.