Any processing technique induces orientation in a polymeric system. We have developed techniques originally explored by R. Zbinden spectroscopy Di Hical Polymers, Academic Press, N.Y.,1964) and P.G.Schmidt (J.Polym.Sci. Al, 1271, 1963) to study the trichroic orientation effects. Using a tilting procedure the principal axes of the absorption ellipsoid are calculated and the isotropic-equivalent or structure factor (Ao) spectrum is found. With trichroic information the assumption of transverse isotropy in one-way drawn samples is no longer necessary and, in fact, is shown to be invalid in some cases. The method is applied to two polymer systems, polyethylene terephthalate (PET) and polyvinylidene fluoride (PVDF). In PET the rotational isomeric content in the crystal and amorphous phases is characterized from the Ao spectra by the method of least-squares curve-fitting. In PVDF, frequency shifts in the plane perpendicular to the draw direction are observed indicating single crystal-like orientation behavior.