| 摘要 |
FIELD: physics.SUBSTANCE: protective element comprises a transparent base layer and a partially reflecting layer on the base layer. The element also comprises a transparent filling layer on the reflecting layer. The reflecting layer in the subject region is structured to form multiple partially transparent micromirrors which, owing to directed reflection of incident light when viewing the subject region from above, demonstrate a distinguishable subject. The refraction indices of the base and filling layers in the visible spectrum differ by not more than 0.2, so that the subject which is distinguishable when viewed from above cannot be recognised when the subject region is viewed through.EFFECT: obtaining an optically variable protective element with high counterfeit protection with high recognisability and improved verification.19 cl, 15 dwg |
