US 12,344,024 B2
Optical security element
Vladimir P. Raksha, Santa Rosa, CA (US); and Cornelis Jan Delst, Fairfax, CA (US)
Assigned to VIAVI SOLUTIONS INC., Chandler, AZ (US)
Filed by VIAVI SOLUTIONS INC., Chandler, AZ (US)
Filed on Mar. 4, 2024, as Appl. No. 18/595,021.
Application 18/595,021 is a division of application No. 17/839,013, filed on Jun. 13, 2022, granted, now 11,945,255.
Claims priority of provisional application 63/210,365, filed on Jun. 14, 2021.
Prior Publication US 2024/0198715 A1, Jun. 20, 2024
Int. Cl. B42D 25/369 (2014.01); B42D 25/40 (2014.01)
CPC B42D 25/369 (2014.10) [B42D 25/40 (2014.10)] 2 Claims
OG exemplary drawing
 
1. A method of producing an optical security element, comprising:
moving a substrate, in a feed direction, between a first planar surface of a first cylinder including a first magnet and a second planar surface of a second cylinder including a second magnet, wherein the substrate has a planar surface that is parallel to the first planar surface and the second planar surface; and
rotating the first cylinder and the second cylinder at same speed as the substrate;
wherein a composition including a plurality of magnetizable platelets is present on a surface of the substrate.