Patent ID: 8562026
Filing Date: 2013-10-22
Classification: B42D,G02B,Y10T

Abstract:
1. A security element having a top side and an underside, wherein the security element has a transparent layer with a non-homogenous refractive index, thereby having a refractive index variation in which a plurality of Bragg planes are formed in said transparent layer by said refractive index variation, wherein the transparent layer is of a layer thickness of between 5 μm and 200 μm and wherein the transparent layer has a plurality of first zones of a smallest dimension of less than 300 μm, which are arranged in accordance with a first grid raster in a one-dimensional or two-dimensional succession in mutually adjacent relationship and wherein, in said first zones, the Bragg planes are respectively shaped in said transparent layer to provide a respective transmissive optical imaging function.