MEASURING INSTRUMENT FOR TOTAL REFLECTION INFRARED ABSORPTION SPECTRUM

摘要

PURPOSE:To attain the analysis of depth in the whole infrared wavelength range at the same time by interposing an inorganic compound which has a smaller refractive index than crystal and is transparent to infrared light as a spacer between the crystal and a sample to be measured. CONSTITUTION:Infrared light 2 from an infrared light source 1 is made incident on the crystal 5 in a sample holder 4 through a Michelson's interferometer 3 and then propagated in the crystal 5 while reflected totally and repeatedly by the boundary surface between the crystal 5 and spacer 6. The reflected infrared light 2' from the crystal 5 contains information on the absorption of the object sample 8 and is detected by a detector 9 and converted and processed by a data processor 10 to obtain the total reflection infrared absorption spectrum. Then, the spacer 6 uses an organic compound such as ZnSe, PbF2, etc., as a material which has the lower refractive index than the crystal and causes the absorption of the spacer in an infrared wavelength range and is transparent to the infrared light. Further, the thickness of the spacer 6 is made variable to attain the analysis of depth.