MANUFACTURED PRODUCT WITH OPTICALLY ENCODED PARTICLE TAG AND ID METHOD

摘要

The invention concerns an article of manufacture that is a manufactured product marked with a microparticle and a method of marking manufactured produces. The microparticle tag includes a predetermined code embedded in its physical structure by refractive index changes between different regions of the particle. The particle has a diameter of a few hundred microns or less and has a plurality of layers.

主权项

1. An article of manufacture, comprising:
a manufactured product marked with a microparticle, wherein the microparticle is incorporated into the manufactured product; and the microparticle has a diameter of a few hundred microns or less and comprises
a first porous layer having a predetermined first porosity and thickness; anda plurality of n additional porous layers having predetermined thicknesses and porosities, at least one of which has a predetermined porosity differing from said first porosity; whereinsaid predetermined porosities and thicknesses of said first porous layer and said n additional porous layers are configured to produce an interference pattern in the reflectivity spectrum having a distinct series of peaks such that the interference pattern forms an optical signature having a particular predetermined code determined by the porosities and thicknesses of said first porous layer and said n additional porous layers.