Surface Topology Specific Metasurface Holograms

Abstract

Metasurface holograms are usually realized on flat surface topologies. Here we show that flexible holographic metasurfaces can be designed to form an image when applied to arbitrary substrate shapes. We demonstrate that for non-flat surfaces the phase contribution of the substrate determines the symmetry properties of the image. The sensitivity of the hologram to the specific surface topology can be enhanced by engineering the distribution of the phase elements in the metasurface area. The results of this work pave the way for practical applications in security printing technologies, in addition to surface topology and polarization sensors.

Holography Using Curved Metasurfaces

“…Changing the MS shape will then result in a distorted holographic image. Our chosen holographic MS design used, as Pancharatnam-Berry dephasing elements, a regular array of gold nanorods sitting on a polymeric spacing layer deposited on a reflective gold backplane [34,35]. Fabrication details are provided in the Methods and Materials section.…”

“…For the nonflat MS case, Equation 2only holds approximately true when both the phase contribution from the polarization [34]. There is a small residual phase distortion, however, which is the result of the relative dephasing between z I − z O and z I + z O for the two surface topology configurations.…”

Metasurface-based compact light engine for AR headsets

“…Obviously, other types of flat tunable lenses, such as liquid crystal ones 38 can also be used for this purpose. Conformal metasurfaces 39,40 provide additional design degrees of freedom by allowing for the metasurface to be non-planar. In addition to higher diffraction efficiencies and lower stray light, one of their main advantages over their conventional Fresnel counterparts is that the metasurface phase profile does not need to have the same symmetries of the underlying surface since the phase profile is defined lithographically in a different step.…”

Electromagnetic metasurfaces: physics and applications

“…Except for EM cloaking, conformal metasurfaces can be utilized to achieve other fascinating physical effects, which form important research directions [315][316][317][318][319][320]. For instance, Faraon's group proposed to decouple the optical properties of an object from its physical shape by capping a thin and flexible metasurface on the object conformally.…”

“…For any given object, one can use the developed theory to design an appropriate metacoating to cover it, in order to achieve the desired optical effects, such as anomalous diffraction and optical illusion [316]. Moreover, conformal metasurfaces can also be employed to realize even more complex functionalities, such as displays [317] and holograms [318,319]. 4.…”