1 January 1999 Gratings of constantly varying depth for visual security devices
Author Affiliations +
Optical Engineering, 38(1), (1999). doi:10.1117/1.602064
Abstract
Sinusoidal gratings of locally varying profile depth are incorporated into diffractive optically variable image devices (DOVIDs) for document security. The variation in profile depth is tailored to specific visual effects that can be readily authenticated. While the diffractive characteristics of these gratings depend very sensitively on the depth, the security of these DOVIDs is inherent to the diffractive structures insofar as the exact reconstruction of the original profile is required for the realization of the original visual effects. Sinusoidal gratings of locally varying profile depth are very resistant against copying by standard holographic techniques since these techniques are shown to lead to a loss of fidelity in profile form or depth.
Rene Staub, Wayne Robert Tompkin, Andreas Schilling, "Gratings of constantly varying depth for visual security devices," Optical Engineering 38(1), (1 January 1999). https://doi.org/10.1117/1.602064
JOURNAL ARTICLE
10 PAGES


SHARE
RELATED CONTENT


Back to Top