A detailed view into the problematics of diffraction on the structure of synthetic stereogram of dot-matrix type is presented. The diffractive structure, composed of elementary diffractive gratings, is described, as well as the process of diffraction. The distribution of the diffracted light is very important because the diffracted wave in fact provides the observation of the stereogram, and is thus crucial for its spatial perception. The relations between a behavior of the diffracted wave and parameters of the stereogram structure are calculated. The presented results help to find the optimal balance between the conception of a designer and the technical possibilities for synthetic stereography.