Infrared emission spectra of thin polymer layers on flat aluminum plate have been measured using Fourier transform infrared spectrometry. The detection limit of Fourier transform infrared emission spectrometry (FT-IR-EMS) was found to be comparable with that of Fourier transform infrared reflection absorption spectrometry (FT-IR-RAS) when an emission ray was collected at a viewing angle of 70°. The merits of FT-IR-EMS over FT-IR-RAS were demonstrated in the measurement of nonflat surfaces. The residual lubricant on steel tire cords could be detected efficiently by the FT-IR-EMS mode. The linear relationship found between the relative emission intensity and the thickness of film represents the possibility for a quantitative analysis of a thin overlayer on metal surface.
Y. Nagasawa and A. Ishitani, "Application of Fourier Transform Infrared Emission Spectrometry to Surface Analysis," Appl. Spectrosc. 38, 168-173 (1984)