The invention relates to a system for shifting at least one light spot (903), said system comprising: —a phase-modulator (906) for generating, from an input light beam, a light beam which is phase-modulated according to a controllable phase profile, —an array of apertures (902) for generating said at least one light spot (903) from said phase-modulated light beam, a change of the phase profile implying a shift of said at least one light spot (903). Use: Optical storage