An electrical element includes an optically-detectable pattern of embedded information. A plurality of thin-film layers is applied on the surface of the substrate wherein one or more of the thin-film layers is at least partially transparent. The plurality of thin-film layers overlaps in an encoding region to form an optical layer structure, wherein at least one of the thin-film layers in the optical layer structure contributes to an electrical function of the electrical element. At least one of the thin-film layers in the optical layer structure includes an information-encoding pattern which contributes to an optically-detectable interference image when illuminated by incident light, and wherein the optically-detectable interference image corresponds to at least a portion of the pattern of embedded information.