Dynamic security device
AssigneesNational Research Council of Canada, Bank of Canada
InventorsDaniel Brassard, Lidija Malic, Keith J. Morton, Teodor Veres, Charles D. MacPherson, Theodoros Garanzotis
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Abstract
A security device that elicits at least one dynamic response upon acceleration, or upon change of orientation with respect to gravity, wherein the dynamic response continues after cessation of the acceleration or the change of orientation. In addition, the dynamic response can be optical, such that it is visually observable by an unaided human eye. Alternatively, the response can be machine readable. In some cases, the dynamic response has duration of from about 0.01 s to about 100 s, or from about Is to about 10 s.
Claims18
A security device that exhibits at least one dynamic response upon change of orientation of the security device with respect to gravity, wherein:
- the security device comprises one or more microfluidic chambers filled with a liquid and one or more microscopic elements;
- and
- the dynamic response:
- a) continues after cessation of the change of orientation with respect to gravity;
- and
- b) comprises a transition of the one or more microscopic elements:
- i) from substantial mechanical equilibrium to non-equilibrium upon action of the change of orientation with respect to gravity;
- and
- ii) back to substantial mechanical equilibrium after cessation of the change of orientation with respect to gravity, and
- wherein the one or more microscopic elements undergo at least one of a rotational motion and a translational motion relative to the liquid during the transition, and the volumetric space collectively occupied by the liquid and the one or more microscopic elements is unchanging relative to the rest of the security device throughout the dynamic response.
Dependencies are inferred from the claim text.