Apparatus for analyzing quantum dot security inks
AssigneeUbiQD, Inc.
InventorHunter McDaniel
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Abstract
A security ink is provided which includes a liquid medium having a plurality of quantum dots disposed therein. Upon excitation with a suitable light source, the ink exhibits a quantum yield greater than 30%, and a photoluminescence which has a lifetime of more than 40 nanoseconds and which varies by at least 5% across the emission spectrum of the quantum dots. Also disclosed are apparatuses for using the same for anti-counterfeit or authentication purposes, which uniquely identifying the presence of photoluminescent materials by spectrally resolving their photoluminescence lifetime.
Claims21
In combination with a security ink containing a first plurality of quantum dots, an optical apparatus for analyzing said security ink, comprising:
- a time-varying light source which excites said security ink, thereby causing said security ink to emit an emission spectrum having first and second distinct regions which are characterized by first and second distinct lifetimes;
- at least one photodetector;
- a first optical element which allows only said first region of said emission spectrum from an optical signal to pass through it;
- a second optical element which allows only said second region of said emission spectrum from an optical signal to pass through it;
- and
- an electronics module which determines the photoluminescence lifetime of said security ink over said first and second regions by monitoring at least one time or frequency response of said at least one photodetector.
Dependencies are inferred from the claim text.