摘要 |
A polarising security element for polarising light of a predetermined wavelength including a first dielectric material having a refractive index nb and at least one polarising region of mutually parallel segments of a second material having a refractive index np which is different from nb, the second material being a dielectric or conducting material. The segments of the second material are in contact with the first material and the segments have a width and/or an average spacing which is less than a predetermined range of wavelengths. A method of manufacturing such a security element in which a relief structure is embossed in the layer of the first dielectric material, the relief structure includes mutually parallel peaks and troughs, and the second layer of dielectric or conducting material is applied on the relief structure to form the at least one polarising region of mutually parallel segments. |