The fabrication of a periodic domain structure in a ferromagnetic thin film is reported. This periodic domain structure is formed in a thin continuous magnetic film by coupling it to a periodic array of magnetic elements grown on top. When the array and the continuous film are exchange decoupled, magnetostatic interactions produce in the continuous layer a domain structure replica of the topographic pattern at selected field values. The present work reports a direct confirmation of this periodic domain structure in the flat continuous film by Kerr microscopy, which is responsible for the pure magnetooptic diffraction. The effect on the magnetization processes of oneand two-dimensional structures with different periodicities and dimensions is studied in detail and compared with micromagnetic simulations, for Co and Fe films.