Moire magnification device
A moire magnification device is disclosed, including a transparent substrate carrying: a regular array of micro-focusing elements on a first surface, the focusing elements defining a focal plane; and a corresponding first array of microimage elements located in a plane substantially coincident with the focal plane of the focusing elements. The pitches of the micro-focusing elements and the array of microimage elements and their relative locations are such that the array of micro-focusing elements cooperates with the array of microimage elements to generate magnified version of the microimage elements due to the moire effect. Along at least one axis across at least a first region of the device, the pitch between the microimage elements and/or between the micro-focusing elements continuously varies across the respective array(s), whereby the moire effect causes different degrees of magnification of the image elements to occur.