However, the differences between measurements with s- and p- polarized
light are important, when one wants to detect the effect of thin films on the
measured sample. This can be done by calculating an IR spectrum out of the two
measured spectra with s- and p- polarized light using equation (1). The
corresponding result is shown in figure 2. The spectra of the pure coatings (blue and
green curves in figure 2) hardly change due to this manipulation.