In the experiments on thermotropic liquid crystals in the SmA phase, four generations of FCDs have been observed under optical crossed polars; this is the reason why the simulation has been stopped with four generations although the simulation allows to show up to 10 generations. We do not see higher generations: there is some critical size under which the FCDs do not exist . The macroscopic observations are done when the sample is observed from the top (it means θ=0∘ and φ=90∘). Figure 9a illustrates the simulation corresponding to this experimental situation. Figure 9b corresponds to the visualization of the smectic layers with θ=45∘ and φ=45∘.