Tamperproof security card

Abstract From the Canadian patent

There is disclosed a unique tamperproof security card comprised of a transparent upper layer having narrow parallel lenses on the outer surface, and an image containing substrate, said two layers forming a lenticular system by which images on the substrate are selectively visible depending upon the angle from which the card is viewed. By incorporating into a selectively visible image the information necessary to verify the identity of the cardholder e.g. the, cardholder's photograph or signature the card may be rendered, substantially tamperproof.