Quadrant polarization parameters ΣX_xxx normalized to the intrinsic azimuthal polarization $U_{\varphi }^{\prime }(x,y)$ (upper panels) and differential quadrant parameters ∆X_xxx normalized to the convolved ΣQ_ϕ (lower panels) for Ringi60 models as a function of radius r₀. Full lines give the values for the convolved PSF_G models, and crosses are for convolved PSF_AO models. The filled diamonds are the intrinsic values. For clarity not all ∆U_xxx values are given.