Metasurface-based nanoprinting (meta-nanoprinting) has fully demonstrated its advantages in ultrahigh-density grayscale/color image recording and display. A typical meta-nanoprinting device usually has image resolutions reaching 80 k dots per inch (dpi), far exceeding conventional technology such as gravure printing (typ. 5 k dpi). Besides, by fully exploiting the design degrees of freedom of nanostructured metasurfaces, meta-nanoprinting has been developed from previous single-channel to multiple-channels, to current multifunctional integration or even dynamic display. In this review, we overview the development of meta-nanoprinting, including the physics of nanoprinting to manipulate optical amplitude and spectrum, single-functional meta-nanoprinting, multichannel meta-nanoprinting, dynamic meta-nanoprinting and multifunctional metasurface integrating nanoprinting with holography or metalens, etc. Applications of meta-nanoprinting such as image display, vortex beam generation, information decoding and hiding, information encryption, high-density optical storage and optical anti-counterfeiting have also been discussed. Finally, we conclude the opportunities and challenges/perspectives in this rapidly developing research field of meta-nanoprinting.

Conventional liquid‐crystal (LC) devices can only realize a single‐manipulation of optical amplitude or phase, which hinders the development of LC devices toward ultracompact multifunctional integration. Herein, it is shown LC devices can be readily extended to multifunctional ones without the cost of complex design and fabrication. Specifically, by combining Pancharatnam–Berry phase with orientation‐degeneracy implied in Malus's law, each operation‐unit of LC devices can manipulate the amplitude and phase of incident light separately, representing a new paradigm for designing innovative LC devices. A multifunctional LC device which can display a grayscale pattern right at the surface of LC, while simultaneously project an independent phase‐only holographic image in the far‐field is experimentally demonstrated. More interestingly, with the LC directors tilted with external applied voltages, a new degree‐of‐freedom is provided to modulate the spectral‐response of LC devices, contributing to the distinct function of optical switch. Owing to these unique characteristics of dual‐manipulations and spectrum‐tunability, the proposed multifunctional LCs have promising prospects in information multiplexing, optical communications, spectral measurements, etc.

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.

Metasurfaces have shown unusual abilities to modulate the phase, amplitude and polarization of an incident lightwave with spatial resolution at the subwavelength scale. Here, we experimentally demonstrate a dielectric metasurface enabled with both geometric phase and magnetic resonance that scatters an incident light beam filling the full reflective 2π-space with high-uniformity. Specifically, by delicately reconfiguring the orientations of dielectric nanobricks acting as nano-half-waveplates in a metasurface, the optical power of phase-modulated output light is almost equally allocated to all diffraction orders filling the full reflection space. The measured beam non-uniformity in the full hemispheric space, defined as the relative standard deviation (RSD) of all scattered optical power, is only around 0.25. More interestingly, since the target intensity distribution in a uniform design is rotationally centrosymmetric, the diffraction results are identical under arbitrary polarization states, e.g., circularly polarized, linearly polarized or even unpolarized light, which brings great convenience in practical applications. The proposed uniform-backscattering metasurface enjoys the advantages including polarization insensitivity, high-integration-density and high-stability, which has great potential in sensing, lighting, laser ranging, free-space optical communication and so on.

Featuring with ultracompactness and subwavelength resolution, metasurface-assisted nanoprinting has been widely researched as an optical device for image display. It also provides a platform for information multiplexing, and a series of multiplexed works based on incident polarizations, operating wavelengths and observation angles have emerged. However, the angular-multiplexing nanoprinting is realized at the cost of image resolution reduction or the increase of fabrication difficulty, hindering its practical applications. Here, inspired by the Jacobi-Anger expansion, a phase-assisted design paradigm, called Bessel metasurface, was proposed for angular multiplexing nanoprinting. By elaborately designing the phase distribution of the Bessel metasurface, the target images can be encoded into the desired observation angles, reaching angular multiplexing. With the merits of ultracompactness and easy fabrication, we believe that our design strategy would be attractive in the real-world applications, including optical information storage, encryption/concealment, multifunctional switchable optical devices, and 3D stereoscopic displays, etc.