Levoy and Hanrahan to capture all the rays in free space. [2] The reconstruction of depth refocusing was demonstrated by Isaksen et al. in 2000. [3] However, LF imaging schemes are critically susceptible to a low imaging resolution. For reconstructed LF images, the resolution substantially reduces compared with conventional 2D imaging system images. For LF imaging, the resolution of the reconstructed image is inherently limited by the number of elemental lenses. Based on the Nyquist sampling theorem, [11] the spatial density of the MLA should be increased to obtain an LF image exhibiting improved spatial resolution. Due to the increase in the elemental lens density resulting from the adoption of passive MLAs, however, the angular sampling resolution of LF imaging is unavoidably affected under the condition of an image sensor with a fixed pixel density, since the ray direction sampling decreases for the case of an elemental lens of reduced aperture. So far, several reconstruction schemes have attempted to ameliorate the spatial resolution of the reconstructed images without deteriorating the angular resolution. Deconvolution algorithms [12,13] and wavefront coding techniques [14-16] were developed to reconstruct 3D depth images featuring an enhanced spatial resolution. Yet, the corresponding resolution uniformity is unacceptable for the reconstruction depth information while the resolution is diffraction limited. Other studies focused on enhancing the spatial resolution of LF images by capitalizing on laterally shifted MLAs. Jang and Javidi proposed a resolution-enhanced integral photography system drawing upon a synchronously moving MLA. [17] Lim et al. proposed resolution-enhanced LF microscopy utilizing a moving MLA driven by an electrically controlled piezo-actuator. [18] Due to the presence of the moving MLA translated by an electromechanical system, however, operation is hardly stable requiring additional transducer modules. As a result, the LF imaging system unavoidably becomes bulky, being slow in capturing elemental image arrays. In the meantime, the metasurface, depending on a subwavelength array of optical antennas, has emerged as a prominent planar optical platform in the visible regime, that can flexibly manipulate the phase profile. [19-29] In particular, the metasurface is capable of individually imparting an arbitrary phase to each orthogonal linear polarization. [30-32] Polarization-tuned multifunctional metasurface devices including beam deflectors, [33-35] metalenses, [36-39] waveplates, [40-42] and multi-image metaholograms [43-46] have been introduced. There The light-field (LF) imaging technique can obtain the light intensity and directional ray distribution information by utilizing a microlens array (MLA). Based on the recoded 3D information, full-parallax or depth-slice images can be reconstructed. Due to the limited ray sampling rate of the MLA, however, conventional LF imaging schemes are fatally susceptible to a trade-off between the spatial and angular resolution. To mitigate this issue...
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