Multifold Integration of Printed and Holographic Meta‐Image Displays Enabled by Dual‐Degeneracy

Abstract

By virtue of the unprecedented ability of manipulating the optical parameters, metasurfaces open up a new avenue for realizing ultra‐compact image displays, e.g., nanoprinting on the surface and holographic displaying in the far‐field. The multifold integration of these two functions into a single metasurface can undoubtedly expand the functionality and increase the information capacity. In this study, a minimalist tri‐channel metasurface is proposed and experimentally demonstrated with multifold integration of printed and holographic displaying, which can generate two N‐bit grayscale images and a four‐step holographic image simultaneously. Benefiting from exploiting the degeneracy of energy allocation and the degeneracy of nanostructure orientations, the functionalities of nanoprinting and holography are combined without the need of a large amount of nanostructures with varied dimensions, which would facilitate both the metasurface design and fabrication. The proposed scheme provides a new idea in enhancing the functionality and capacity of metasurfaces without complicating their design, which has promising prospects for applications in ultra‐compact image displays, high‐density optical storage, optical anti‐counterfeiting and many other related fields.

Metasurface-based nanoprinting: principle, design and advances

“…The concept of orientation degeneracy can apply to any anisotropic structure and materials. For example, image display right at the sample surface and holography in the far field are demonstrated with liquid crystals 228 . Furthermore, in 2022, Zhou et al took full advantage of the DOFs of single-celled nanostructures and proposed the concept of dual-degeneracy 229 , that is, the degeneracy of energy allocation and the degeneracy of nanostructure orientations, as shown in Fig.…”

Metasurface‐Assisted Optical Encryption Carrying Camouflaged Information

“…Metasurface is an artificially planar‐structure material that has the superior capability of controlling DOF of light at subwavelength scale, [ 1–8 ] leading to a series of novel optical encryption technologies. [ 9–20 ] For nanoprinting, [ 21–24 ] these DOFs offer the possibility of encoding multiple meta‐images into different optical dimensions, thus improving the security and capacity of optical encryption. By modulating geometric dimension of single‐celled nanostructures in two orthogonal directions, two color meta‐images can be encoded with different polarization light.…”

“…Owing to the abundant degrees of freedom (DOF) of light (e.g., amplitude, phase, polarization, and frequency), optical encryption technology has significant advantages of multi-dimensionality, large capacity, high design freedom, and high security.Metasurface is an artificially planarstructure material that has the superior capability of controlling DOF of light at subwavelength scale, [1][2][3][4][5][6][7][8] leading to a series of novel optical encryption technologies. [9][10][11][12][13][14][15][16][17][18][19][20] For nanoprinting, [21][22][23][24] these DOFs offer the possibility of encoding multiple meta-images into different optical dimensions, thus improving the security and capacity of optical encryption. By modulating geometric dimension of single-celled nanostructures in two orthogonal directions, two color meta-images can be encoded with different polarization light.…”

Multiplexed optical differentiator enabled by single-size nanostructured metasurface

“…Metasurface is a promising candidate to undertake such a challenge. As an artificial planar material composed of sub-wavelength scale nanostructures, metasurfaces can be employed to manipulate the amplitude, phase, frequency and polarization state of incident lightwave precisely with sub-wavelength resolution [20][21][22][23][24][25][26] . Benefiting from the advantages of ultra-compact structure, fabrication process compatible with semiconductor industry and flexible manipulation of electromagnetic waves, metasurfaces provide a new impetus for the development of optical computing devices such as equation solver 27 and analog optical computing [28][29][30][31][32][33][34][35] .…”