Patent ID: 11891527
Assignee: SICPA HOLDING SA
Field: Basic materials chemistry (Chemistry)
Classification: CPC C  B | IPC B  C

Claim 14:
15. A method for authenticating a security document comprising the steps of:
a) providing the security document recited in claim 10;
b) illuminating the machine readable security feature at at least two wavelengths, wherein one of said at least two wavelengths is in the visible range and another one of said at least two wavelengths is in the NIR range,
c) detecting the optical characteristics of the machine readable security feature through sensing of light reflected by said machine readable security feature at at least two wavelengths, wherein one of said at least two wavelengths is in the visible range and another one of said at least two wavelengths is in the NIR range, and
d) determining the security document authenticity from the detected optical characteristics of the machine readable security feature.