Patent ID: 6752432
Filing Date: 2004-06-22
Classification: B42D,Y10T

Abstract:
An information-bearing laminar assembly, comprising an information-bearing inner layer interposed between first and second light transmissive outer layers;the information-bearing inner layer having imagewise halftone pattern of microholes formed thereon, each microhole penetrating at least partially through the thickness of the information-bearing layer such that the light transmissivity of the information-bearing layer within said half-tone pattern is imagewise differentiated at each microhole; the first and second light-transmissive outer layers and said information-bearing inner layer being constructed and arranged such that the first and second light transmissive outer layers cover said imagewise half-tone pattern of microholes and permit transmitted light to reach said microholes; the microholes having sufficiently small structural dimensions such that, under unassisted visual inspection, the imagewise halftone pattern is (a) substantially imperceptible when the information-bearing laminar assembly is viewed in reflection, and (b) substantially perceptible when the information-bearing laminar assembly is viewed in transmission.