Fig. 1. Schematic illustration of multi-plane vectorial holography based on the metasurface. (a) Demonstrated metasurface composed of IP-L nanofins fabricated by femtosecond laser direct writing. (b) By imposing desired amplitude and polarization restrictions to each image plane in the demonstrated Jones matrix holographic algorithm framework, the reconstructed images (“3D,” “PR,” and “INT”) can exhibit inhomogeneous and customized polarization distributions. (c) Basic principle of two-photon polymerization.

Fig. 2. Flowchart of established Jones matrix holographic algorithm framework for generating multi-plane holographic images with customized polarization distributions. The number of total image planes is represented by N. The propagation processes between the hologram plane and each image plane are calculated based on the Fresnel transform (FrT) and inverse Fresnel transform (IFrT) in matrix framework, respectively.

Fig. 3. Simulated transmitted efficiencies txx and tyy of nanofins with different lengths, widths, and heights. (a) An IP-L nanofin set on a glass substrate is chosen as the meta-atom to constitute the demonstrated metasurface. (b)–(d) Amplitude [abs(txx), abs(tyy)] and phase (φxx, φyy) of simulated transmitted efficiencies txx and tyy of nanofins with different dimensions based on RCWA method. In the simulation, the length L, width W, and height H are simultaneously swept. The length L and width W of the nanofin are both swept in the range of 350 nm to 800 nm, with an interval of 10 nm. And the height H of the nanofin is swept from 3 μm to 5 μm, with an interval of 200 nm.

Fig. 4. (a), (b) Scanning electron microscopy images of our fabricated metasurface sample from top and side views. (c) Experimental setup used in the experiment to capture the multi-plane vectorial holographic images located at different image planes. An objective lens (20×/NA=0.45) and a CCD constitute the imaging system. By adjusting the distances between the metasurface and the imaging system, the images located at different planes can be successfully captured. The fabricated metasurface is composed of 640×640 IP-L nanofins with different dimensions (L and W, 350–800 nm, H, 3–4.6  μm, and P, 1.1  μm) as well as orientation angles (θ, −90° to 90°).

Fig. 5. Simulated and experimental results of the reconstructed multi-plane vectorial holographic images under different configurations of LP1 and LP2. The red and blue arrows indicate the input and output polarization components (see Visualization 1).