Název:
A sampler of diffraction and refraction optically variable image elements
Autoři:
Horáček, Miroslav ; Krátký, Stanislav ; Matějka, Milan ; Chlumská, Jana ; Meluzín, Petr ; Pirunčík, J. ; Aubrecht, I. ; Kotrlý, M. ; Kolařík, Vladimír Typ dokumentu: Příspěvky z konference Konference/Akce: International Conference on Nanomaterials - Research & Application /13./ NANOCON, Brno (CZ), 20211020
Rok:
2021
Jazyk:
eng
Abstrakt: Diffraction and refraction optically variable image elements are basic building blocks of planar structures for advanced security of documents and valuables. A sampler formed by an array of 36 diffraction structures binary, tertiary, quaternary and blazed gratings (period range 400 nm 20,000 nm) represents a cross-section throughout technological steps mastering, galvanic replication and embossing. Electron-beam writing technology with Gaussian beam and electron energy of 100 keV, with very small forward scattering of high energy electrons and with the possibilities to create a linear grating with the minimal period of 100 nm, was used to create the master. An important advantage of high-resolution electron-beam lithography is its substantial flexibility in combining possible planar structures with significantly different parameters, such as very dense and relatively shallow structures together with deep structures (approx. 10 microns) with precise shapes (micro-lenses or Fresnel structures). For protection of documents and valuables, interesting results are induced with planar optical structures consisting of non-periodic arrangements, which are characterized by high robustness to counterfeiting and imitation. While the origination process is available for grating period down to 100 nm, the mass replication technology appears to be a bottleneck of the entire technological process. Measurement of topology and profiles of the structures by atomic forces microscope and documenting the quality of technological process of the three steps of replication of planar optically variable elements was performed for all 36 structure types of sampler.
Klíčová slova:
diffraction; e-beam writer; embossing; galvanic replication; mastering; optically variable image element; refraction; security; valuables Číslo projektu: VI20192022147 (CEP) Poskytovatel projektu: GA MV Zdrojový dokument: NANOCON 2021 - Conference proceedings, ISBN 978-80-88365-00-6, ISSN 2694-930X Poznámka: Související webová stránka: https://www.confer.cz/nanocon/2021/4371-a-sampler-of-diffraction-and-refraction-optically-variable-image-elements
Instituce: Ústav přístrojové techniky AV ČR
(web)
Informace o dostupnosti dokumentu:
Dokument je dostupný v příslušném ústavu Akademie věd ČR. Původní záznam: https://hdl.handle.net/11104/0336321