Ratio of scattered (panel a) and polarized (panel b) flux to the disk scattered flux averaged over the 4π solid angle as a function of disk inclination and HG scattering asymmetry parameter. Panel c: ratio of scattered to polarized flux for an optically thin debris disk. The ratios (panel a and b) define the view factors f_{sca λ} and f_{pol λ}, respectively. The ratios presented in this figure are calculated using the HG function (as SPF) and Rayleigh-like function with p_max = 0.3 (as polarization fraction phase function). For a different value of p_max the factor f_{pol λ} should be linearly scaled.