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Due to the precise and continuous regulation of phase, holographic encryption based on metasurfaces and liquid crystals (LCs) has been proposed to encrypt the information by manipulating the wavelength, polarization, etc. However, the security cannot be fully guaranteed since the requirements of decoding methods for these schemes are generally not very strict and vulnerable for exhaustive attack. Furthermore, any part of the hologram stolen may lead to the disclosure of the hidden information regardless of the generation mode of phase delay or the selection of media material, so the security needs to be further improved. Here, inspired by Tiger Amulet, embodying the encryption consciousness of ancient China, we propose a simple but effective encryption method and design a “four-in-one” hologram based on photopatterned LCs. Specifically, the most important encrypted image can only be displayed when the four LC holograms in the same group are spliced into a whole according to the designed order. On the contrary, the camouflage information would be displayed if the holograms are placed in the optical path separately or spliced in wrong order. It is even more interesting that with the LC directors tilted with applied external voltages, the holographic efficiency of the LC hologram will change accordingly. This sets further demanding requirement on the decryption condition and thus increases the encryption security. With the advantages of simple design, high security, and low crosstalk, our encryption scheme has great potential in the fields of information hiding and image encryption.

Metasurface‐assisted nanoprinting is usually enabled by spectrum‐modulation and/or polarization‐modulation at the subwavelength scale. The spectrum‐modulated nanoprint works under unpolarized white‐light and requires the minimalist observation conditions, but it can hardly modulate light brightness; the polarization‐modulated nanoprint can continuously control light brightness, but it requires complex and precise polarization control both at the input and output ends to decode a nanoprinting image. In this study, computer‐generated holographic nanoprinting is designed and experimentally demonstrated, enabled by Pancharatnam–Berry phase modulation of light, which has both the advantages of the two types of nanoprintings while avoiding their disadvantages. Specifically, a general platform is built to implement single‐channel/multichannel/color nanoprinting in a holography way, which presents its unique characteristics like incoherent light illumination, arbitrary brightness modulation, polarization insensitivity, and zero‐dispersion. A periodic phase is further attached to the target object wave during the holographic interference pattern generation, and the reconstructed nanoprinting image only appears in the zero‐order diffraction direction, thus making the information delivery safer. This study can empower advanced research on metasurface‐based nanoprinting, which can find its markets in ultracompact image‐display, data storage, information multiplexing, and many other related fields. [ABSTRACT FROM AUTHOR]