The dependence of the depolarization ratio on the slitwidth has been investigated for some polarized Raman bands. It is found that the ratio of the peak intensities depends on the slitwidth, whereas the ratio of the integrated strengths does not. This behavior is explained in a general way by considering the different contributions of the isotropic and the anisotropic spectrum to the two terms of the depolarization ratio.
Giancarlo Fini and Paolo Mirone, "Slitwidth Dependence of Depolarization Ratios," Appl. Spectrosc. 29, 230-232 (1975)