The influences of various factors of dielectric target in certain pick-up tubes, storage devices and electro-optic display devices on the resolution are studied in this paper. By considering the general case of anisotropic dielectric target, the optical transfer function (OTF) from surface charge raster pattern to potential or optical pattern of dielectric target is deduced. The resolution limit of the dielectric target is analyzed quantitatively. The leakage of electricity on surface and the influence of the other medium film layer introduced on target surface on the resolution are discussed in detail. For example, the MTF curves of silicon target in pick-up tubes, polystyrene target in video tape and anisotropic medium target of DKDP crystal in large screen projection TV are calculated by TQ-16 type computer, then the resolutions of these targets are found accordingly. The results obtained well coincide with the experimental curves and data in literatures. Finally, the calculation results are further confirmed by experiments on DKDP crvstal.