METHOD FOR MEASURING TOTAL REFLECTION INFRARED ABSORPTION SPECTRUM

摘要

PURPOSE:To analyze the depth in a total IR light wavelength region at one time by using an inorg. compd. having no absorption in the wavelength region of IR light as a spacer. CONSTITUTION:The IR light 2 emitted from an IR light source 1 passes through a Michelson interferometer 3, is made incident on a crystal 5 in a sample holder 4 and is totally reflected by the boundary between the crystal 5 and the spacer 6. The inorg. compd. such as ZnSe or PbF2 which has the refractive index lower than the refractive index of the crystal 5 and is transparent to IR light is used for the spacer 6. Part 7 of the incident IR light bleeds to a measuring sample 8 beyond the boundary, is reflected by receiving the effect of the absorption by the sample 8 and is detected by a detector 9. The detected light is processed by a data processor 10 and the total reflection IR absorption spectrum is obtd. The penetration depth of the IR light 7 penetrating into the sample 8 in the stage of total reflection changes when the thickness of the spacer 6 is changed. The depth analysis is thus made possible. The depth in the total IR wavelength region is thereby analyzed without receiving the effect of absorption by the spacer.