Modulated Surface Relief Structure

摘要

A hidden image security method is disclosed including the steps of obtaining first and second parts of an encoded hidden image corresponding to an original image; providing a light transmissive substrate; applying the first part of the encoded hidden image to the light transmissive substrate in the form of a plurality of focussing elements; displaying the second part of the encoded hidden image to a display screen of an electronic device; and superposing the plurality of focussing elements of the security document or device over the second part of the encoded hidden image on the display screen to decode and reveal the encoded hidden image.