All-medium metasurface color printing and holographic encryption co-modulation method

Abstract

The invention relates to an all-medium metasurface color printing and holographic encryption co-modulation method, which belongs to the technical field of micro-nano optics. The method uses an amorphous silicon-coupled polar antenna and an amorphous silicon nanorod antenna with different spectral responses to spatially arrange a color-printed target pattern on the metasurface, the in-plane azimuthis used at the same time to take a pixel as a unit to code the spatial phase distribution of a metasurface hologram corresponding to a different wavelength, the metasurface color printing technologyand a wavelength-multiplexed metasurface hologram set are integrated in a single-layer all-medium metasurface. The all-medium metasurface is rendered as a micro-color image under the illumination of white light. Different holographic reconstruction images are reconstructed in a far field under irradiation of coherent monochromatic lasers with specific wavelengths, and the information capacity is extremely high. The invention also provides a method of hiding secret information, which has great potential in many fields such as data storage, holographic display, information encryption, and forgery prevention.

Description

technical field [0001] The invention relates to a metasurface wavefront modulation method, in particular to a method for co-modulating all-dielectric metasurface color printing and holographic encryption, and belongs to the technical fields of micro-nano optics, structural color printing, holographic display, and information encryption applications. Background technique [0002] Metasurfaces are usually composed of periodic, quasi-periodic, or randomly arranged metal or dielectric nanoantenna arrays with subwavelength dimensions, which can perform high-resolution modulation of the amplitude and phase of the light field on a subwavelength scale, and are used in data storage, information processing, Beam shaping, micro-nano holography, polarization control and other fields have great potential. Among them, micro-nano holography, which combines holographic principles with metasurfaces, is a cutting-edge hot field. This technology can promote the miniaturization of holographic d...

AI Technical Summary

Problems solved by technology

Obviously, the design and processing of the basic modulation unit composed of integrated structures of this kind of metasurface are relatively complicated and inefficient.

[2]Yoon,G.,Lee,D.,Nam,K.T.&Rho,J."Crypto-Display"in Dual-Mode metasurfaces by simultaneous control of phase and spectral responses[J].ACSNano,2018,12:6421-6428 .Different structural colors were modulated by using two dielectric nanoantennas in the color printing mode, but the structure was not optimized for the metasurface hologram mode, resulting in the two dielectric nanoantennas corresponding to the same One wavelength, only one holographic image can be recorded), and these reported methods either have defects of complex design, difficult processing, or insufficient controllability, and can only record a holographic reproduction

[0004] The above drawbacks greatly limit the practical application prospects of these methods

At present, there is almost no metasurface with simple processing, strong controllability, recording multi-level holographic information through wavelength multiplexing, and simultaneously modulating spectral and spatial information.

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