Synthesis of nano-optical elements for zero-order diffraction 3D imaging

Abstract

A method is proposed to compute and synthesize a microrelief to produce a new nano-optical element for forming 3D images with full parallax at the zero order of diffraction. The synthesis of nano-optical elements requires the use of multilevel structures. Optical security elements that produce the new security feature are synthesized using electron-beam lithography. The accuracy of microrelief formation is 10 nanometres in terms of depth. A sample optical security element is manufactured, which when illuminated by white light, forms a 3D image at the zero order of diffraction. The new optical security feature is easy to control visually, safely protected against counterfeiting, and designed to protect banknotes, documents, ID cards, etc.