Security device
摘要:
A security device with multiple layers. A substrate provides the backing to a first luminescent layer. An optically variable structure is positioned between the first luminescent layer and a second luminescent layer. Both the first and second luminescent layers emit luminescent radiation when stimulated. When the first layer is stimulated, the optically variable structure filters the emitted luminescent radiation such that the emitted luminescent radiation only escapes the optically variable structure at a predetermined range of emission angles. A user, when viewing the security device from the predetermined range of angles as both layers are stimulated, can see a completed image of a predetermined indicia. When the security device is viewed at angles other than the predetermined range of angles as both layers are stimulated, a user will only see an incomplete image of the predetermined indicia.
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