KTU Develops New Technique for Labels

Researchers at KTU (Kaunas University of Technology) Institute of Material Science in Lithuania have developed a new method to produce holographic security labels combining dot-matrix and e-beam.

Dot-matrix, which utilises computer-generated holographic images comprised of an array of diffractive microscopic dots written by interfering laser beams, is relatively fast and cheap. The technique is used to expose large areas of the hologram. As it does not provide a very high level of protection, electron beam lithography, which utilises an electron beam rather than a laser beam and is generally inaccessible to counterfeiters, is then used to expose smaller areas of the hologram, creating high- resolution structures.

According to the KTU team, the method allows the two technologies to be combined so that the final security device could contain electron beam patterned high resolution diffraction gratings, as well as dot-matrix laser patterned large hologram areas with high diffraction efficiency, providing an increased level of protection.