A method for projecting a 3-D viewable image onto a display surface, comprising the steps of, providing two or more projection systems; arranging the two or more projection systems into a first group and second group, wherein the first group and second group each comprise one or more projection systems; arranging the first and second group of projection systems such that each group of project systems can project an image on a display surface and configuring the first and second group of projection systems such that the first and second group of projection systems alternately project onto the display surface.