Personalized authentication of products using terahertz waves
A method for authenticating an article is provided, comprising the following steps in a reference signature generation phase: acquiring a reference density image of a volume beneath a reference area of the article using a proximity terahertz imager array; and generating and storing a reference signature associated with the article from the reference density image.
1 . A method for authenticating an article, comprising the following steps in an end-of-production phase of the article:
defining on the article a reference zone with a random internal texture resulting from a production process of a material of the article;
applying a visible marking directly on a surface of the article at a location corresponding to the reference zone, wherein the visible marking guides placement of a terahertz proximity imager during subsequent authentication;
acquiring a density image of a volume of material beneath the reference zone using a terahertz proximity imager positioned according to the visible marking;
generating a reference signature from the density image; and
recording the reference signature in an authentication system with a unique identifier associated with the article, wherein the authentication system is configured to:
receive a current density image of the article's reference zone acquired during a subsequent authentication phase; and
return the reference signature associated with the article using the unique identifier.
2 . The method according to claim 1 , comprising the following steps in a subsequent authentication phase of the article:
finding the reference zone on the article using the visible marking;
acquiring the current density image of the article's reference zone using a terahertz proximity imager;
receiving the reference signature associated with the article from the authentication system; and
searching for the reference signature in the current density image.
3 . The method according to claim 1 , wherein the imager comprises a pixel array larger than the reference zone.
4 . The method according to claim 3 , wherein the reference signature is a sub-image including a sequence of pixels aligned in the reference zone.
5 . The method according to claim 3 , wherein the reference signature is a sub-image including the reference zone.
6 . The method according to claim 4 , comprising the following step:
segmenting pixel values of the imager into a number of levels smaller than a bit resolution of a pixel.
7 . The method according to claim 6 , comprising the following step:
segmenting the pixel values into three levels.
8 . The method according to claim 1 , wherein the proximity terahertz imager is integrally implemented in CMOS technology.
9 . The method according to claim 8 , wherein the proximity terahertz imager is a lensless reflection imager.
10 . The method according to claim 8 , wherein the terahertz proximity imager is a near-field imager.
11 . The method according to claim 5 , comprising the following step:
segmenting pixel values of the imager into a number of levels smaller than a bit resolution of a pixel.
12 . The method according to claim 11 , comprising the following step:
segmenting the pixel values into three levels.