SECURITY FEATURE COMPRISING A PERFORATION PATTERN

摘要

The invention relates to a document to be protected against forgery comprising a security feature in the form of a perforation pattern, wherein the perforation pattern extends over a surface of the document and represents an image comprising brightness tones. The perforation pattern is herein formed such that, for instance when the thus treated document is held up to the light or placed on a light box, an image becomes visible at the location of the perforation pattern. It will be apparent that arrangement of such an image representing brightness tones requires extremely advanced technologies. Such technologies are not easily accessible to potential forgers, so that documents thus provided with such a perforation pattern are very difficult to forge. The perforation pattern is preferably applied by means of laser light.