A method of making a security device, comprising: forming an array of primary focusing elements on a first region of a focusing element support layer, by applying at least one transparent curable material either to the focusing element support layer or to a casting tool carrying a surface relief over an area which includes at least the first region, the surface relief comprising portions corresponding to the primary focusing elements; forming the transparent curable material(s) with the casting tool; and curing the transparent curable material(s) so as to retain the surface relief in the first region; wherein the surface relief further includes a plurality of structures of greater depth than the height of the primary focusing elements such that the cured transparent material(s) include a plurality of features protruding above the height of the primary focusing elements between primary focusing elements of the array.