The invention provides a method of producing a security feature in an identification document. A core including a top surface and a bottom surface is provided. A first laminate is laminated in contact with the top surface. A second laminate is laminated in contact with the bottom surface, the laminated...http://www.google.com.au/patents/US20040011874?utm_source=gb-gplus-sharePatent US20040011874 - Laser etched security features for identification documents and methods of making same
