A self-authenticating article comprising a substrate having an image receiving surface and a lenticular lens is provided. The lenticular lens has a predetermined lens frequency and is configured for optically decoding encoded indicia viewed therethrough. The lens is attached to the substrate so that...http://www.google.ca/patents/US7654580?utm_source=gb-gplus-sharePatent US7654580 - Self-authenticating documents with printed or embossed hidden images
