| 摘要 |
A method of checking the authenticity of a perforation pattern which serves as a security feature and which when viewed in daylight back-lighting shows image information in the substrate of a document in particular in card form, wherein both the front side and also the rear side of the substrate is viewed in the region of the perforation pattern under incident light with light of a defined wavelength and in that case the image which is inherent to the perforation pattern shows on the front side while on the rear side thereof an area corresponding to the region of the perforation pattern shows up only in unspecified fashion. |
