Holographic colour prints for enhanced optical security by combined phase and amplitude control

• DOI: 10.1038/s41467-018-07808-4
• Publication Date: 2018-12-28T11:30:12Z
• Authors: Kevin T. P. Lim; Hailong Liu; Yejing Liu; Joel K. W. Yang
• Keywords: Nanoimprint lithography

We created a novel optical security device that integrates multiple computer-generated holograms within single colour image. Under white light, this "holographic print" appears as image, whereas illumination with red, green, or blue beam from handheld laser pointer projects up to three different onto distant screen. In our design, all dielectric layered pixels comprising phase plates (phase control) and structural filters (amplitude are tiled form monolithic print, wherein pixel-level control over the amplitude of light allows us simultaneously achieve hologram multiplexing image formation. The entire print is fabricated in lithographic process using femtosecond 3D direct writer. As information encoded surface relief structures, prints can be manufactured nanoimprint lithography could find applications document security.