A security document with a see-through feature, and methods for manufacturing and authentication thereof

摘要

A method for manufacturing a security document by providing transparent external layers (101, 102), at least one semi-transparent internal layer (103-106) with a see-through area (110) which is more transparent than the majority of the remainder of the document, laminating the layers (101-106) to form the security document and applying to the document, before and/or after lamination of layers (101-106), personalized data (121-123) and a see-through security feature in the see-through area (110), the see-through feature comprising a first partial image (111) applied on one side of the at least one semi-transparent internal layer (104) and a second partial image (112) applied on the other side of the at least one semi-transparent internal layer (104), wherein the first and second partial images (111, 112) form a complete image (113) when viewed in transmitted light. The method further comprises the steps of, before applying the see-through security feature: obtaining the personalized data (121-123) for the security document, obtaining the complete image (113) for the see-through security feature, and dividing the complete image (113) to the first partial image (111) and to the second partial image (112) using a function having a value dependent on at least part of the personalized data (121-123) for the security document.